Monday, April 10, 2017

On Reports Of Putative Relict Pterosaurs: A Reappraisal

While I have written about reports of alleged surviving relict pterosaurs on this blog before, I took a mostly critical and sceptical perspective, in which I pointed out that, as the reports do not seem to describe what is now known about pterosaur anatomy from the fossil record, I deem the said reports unlikely to actually be describing living pterosaurs. At the time, I wrote that misidentifications of known animals, such as bats and birds, are likely the main culprits, with perhaps some reports possibly representing encounters with unknown species of birds and bats. However, a recent reappraisal of the situation, spurred by my becoming aware of some more reports that seem to be describing morphological features known in pterosaurs from the fossil record, and that, additionally, are obscure features not known to the average layperson, has inspired me to revisit this topic and reconsider my thoughts on the issue of these purported mystery animals.

On an article (http://www.mysteriousuniverse.org/2016/07/mysterious-living-dinosaurs-of-the-wild-west/) on the weblog Mysterious Universe, the following report is detailed:

"In 2012, another witness claimed to have seen what appeared to be a baby pterodactyl under a bridge in Tucson, Arizona. The winged creature was said to have a wingspan of around 8 feet, and to be covered in whitish fur, with a head sporting a "top knot" that appeared to be molting. The strange creature was apparently quite aggressive towards the intruders, spreading its wings, hissing, and assuming an attack stance."

What immediately stood out to me from this report is that the putative juvenile pterosaur is described as being covered with "whitish fur," much like the pycnofibres (fur-like integumentary structures) that fossils of pterosaurs from the Mesozoic Era show them to have possessed. This is in stark contrast to the other reports which seem to describe scaly- or leathery-skinned winged monsters, with nary a semblance to the actual prehistoric ornithodiran, or avemetatarsalian, archosaurian winged reptiles of the Mesozoic Era. Not only is this feature of the report anatomically accurate, but, notably, pycnofibres are also a relatively obscure anatomical feature that the average layperson, exposed to naked-skinned Flintstones-esque inaccurate portrayals of pterosaurs, would not be overtly familiar with.
This renders the above report more impelling, in my eyes, than most.

Yet another realization I have had is that, as pterosaurs' bones tended to be relatively hollow and lightweight, like those of birds (an adaptation to flight), it would seem less implausible for them to have a 66-million-year-long ghost lineage between the end of the Cretaceous Period and the present-day. The criticism of the idea that surviving prehistoric species might explain cryptozoological encounters has been made that many of the proposed candidates were in possession of large, dense, bones resistant to erosion, whose fossils would not easily leave a ghost lineage. (However, it shall be noted that even this is not necessarily a tightly-binding rule, as there exists a group of ichthyosaurs -- marine reptiles with large, dense, erosion-resistant bones -- for which a 66-million-year-long ghost lineage exists, the same length of time as has elapsed between the end of the Cretaceous Period and now).
As pterosaurs' bones were relatively light, hollow, and fragile, the idea of them leaving a considerable ghost lineage seems to be, on the face of it, by no means absurd.

So I decided it was time for a reappraisal of my views on the matter. I now view the idea of surviving relict populations of the clade Pterosauria, as, by no means confirmed or likely, but not overly implausible or far-fetched, and a possibility that, while ought still to be parsed skeptically, should be considered, rather than rejected outright, when analyzing cryptozoological reports said to describe creatures similar to them.

Bibliography:
Swancer, Brent. 22 July 2016. "Mysterious Living Dinosaurs of the Wild West". Mysterious Universe. http://www.mysteriousuniverse.org/2016/07/mysterious-living-dinosaurs-of-the-wild-west/

Sunday, March 19, 2017

A New Combined Many Worlds/Multiverse–Quantum Entanglement–Wormhole Model

Once again, I am posting an article that is unrelated to palaeontology, zoology, or biology, but, instead, covers topics in physics and cosmology that, likewise, fascinate me.

In this article, I present my own hypothesis regarding several aspects of quantum physics and cosmology. Here, I propose my own hypothetical model which attempts to combine the Many Worlds Interpretation of quantum mechanics, the numerous Hubble volumes multiverse model, quantum entanglement, ER=EPR/wormholes, and retrocausality/time travel to the past into one unified, elegant model. You might have heard of the concept of a multiverse. If not, I will now proceed to explicate it. A multiverse is a hypothesized plurality of universes that exist. In other words, just as there are planets besides Earth, solar systems besides the one that contains Earth, and galaxies besides the Milky Way, there could, likewise, be other universes besides the one we are inhabiting. Quantum entanglement refers to a process wherein two or more particles are described using the same wave function. This means that anything that happens to one particle will instantly be responded to by the other, regardless of how far apart the particles happen to be. Quantum entanglement was criticized by Albert Einstein, who referred to it as “spooky action at a distance”, as he thought that it was impossible to occur, as it implied the sending of information faster than the speed of light in a vacuum, in contradiction to the postulate of relativity that nothing can travel faster than the speed of light in a vacuum.

First, it is necessary to clarify some basics of quantum mechanics. In quantum mechanics, entities such as light and electrons are in possession of both a particle nature, as well as a wave nature. In other words, they can sometimes behave like particles, and sometimes like waves, depending upon how they are being experimented upon. For example, electrons sent through a sheet containing a pair of slits show interference, like waves, while light is made up of tiny particles, or corpuscles, known as photons, as well as showing wave phenomena such as interference. This means that, just as a mathematical equation can be used to describe the state of a wave at a particular time, as all particles have a wave nature, a wave equation can be used to describe them, as well. In quantum mechanics, the wave equation that is utilized for subatomic particles is referred to as the Schrödinger equation, named after physicist Erwin Schrödinger, who formulated it. A solution to this equation is referred to as a wave function.

Strangely, however, the wave function does not describe exactly where the particle’s location is, but, rather, the probabilities that its location will be in various places. It was once thought by many physicists, including Einstein, that this uncertainness entailed that scientists were unaware of certain information, and that, once this information was to be filled in, the wave function would be able to tell us the particle’s exact location with certainty. In other words, physicists thought that this probability at such tiny scales was no different from the probability we encounter in everyday life, for example, if someone trapped inside a building who has no idea what the weather is outside were to say “There is a 60% probability that it is rainy right now, and a 40% probability that it is sunny right now”. In reality, it would be either rainy or sunny outside right now, but the individual stuck in the building does not currently possess enough information to make the determination as to which one happens to be the case.

More experimental evidence showed that this was, alas, not the case. Rather than merely reflecting scientists’ lack of knowledge, it was shown that the probability at the quantum scale is inherent, meaning that, prior to measurement, a particle really does lack a precise location, and that it subsequently restricts itself to a particular location once it is measured. This baffled physicists profoundly. Many found themselves incredulous, and started searching for explanations. Some of the explanations have included the one that the consciousness of the observer, when observing and measuring the particle, forces it to become restricted to one particular location. Some others have included the process known as quantum decoherence, in which interaction with the environment causes a superposition of states to break down, in a sense, into what appears to be a single state, as the smaller quantum system under observation coagulates into a larger quantum system composed of itself and parts of its environment.

The interpretation of the probabilities of quantum mechanics that this article focuses its attention on, however, is the Many Worlds Interpretation, originally formulated by physicist Hugh Everett III in the year 1957 of the decimal Gregorian calendar. This interpretation states that the probabilities described by the wave function represent a superposition of all of the copies of the object being measured that exist in parallel universes, and that, when the measurement is performed, the observer can only observe the particle that exists in the universe that they are in.

Meanwhile, leaving the realm of quantum mechanics altogether and entering the realm of cosmology, the study of the origins, evolution, and large-scale structure of the universe, and reality, as a whole, it is thought that the amount of space in the universe beyond that which we can detect, due to the light from there not having had sufficient time to reach us yet, might be infinite, or finite, but very large. If so, then, as there are a finite number of ways that particles can be arranged to form objects, this would entail that any possible scenario would be able to occur in some region of space. This has led to the formulation of another multiverse theory, known as the cosmological or spatial multiverse model. This model postulates that, in the regions of space beyond that from which light has had sufficient time to reach us, known as our Hubble volume, if you were to travel far enough, by the pure laws of chance and probability, you would eventually come across numerous other Milky Way Galaxies, numerous other Solar Systems like ours within them, and numerous other Earths within them, but each one would be slightly different from ours, in some ways.

For example, on some of these other Earths, situations and characters that are part of fiction in our own Hubble volume would actually be real. There could be a Jurassic Park Universe in which Isla Nublar and Isla Sorna exist, and a company called InGen actually cloned dinosaurs and placed them on the islands, a Full House and Family Matters Universe in which these shows and the characters within them are real (these shows must take place in the same universe, as Steve Urkel from Family Matters once made a cameo appearance on Full House), even a Land Before Time Universe in which dinosaurs' neurological and throats anatomy evolved in such a way that allowed them to evolve the ability to speak, and the characters and situations from that series are real.

The suggestion has been made, and I make it again here, that both of these types of multiverse models -- the one derived from the weird probability superpositions of quantum mechanics, and the one derived from the inferred vastness of space -- might, in fact, be one and the same. In this way, the quantum mechanical superposition of probabilities would constitute a description of all of the copies or versions of an object under measurement, as they exist in separate Hubble volumes, separated by vast expanses of space. The probabilistic nature of the measurement, then, would come about as a result of the mathematical Schrödinger equation and the wave function contained within it not being able to tell you which Hubble volume the observer performing the measurement happens to be situated within.

I find this merging of these two varieties of multiverses to be quite an elegant theory, indeed, and it has the additional benefit of being more parsimonious than proposing two different types of multiverse that contain pretty much largely the same content.

The fact that the same wave function would describe these various particles, in different Hubble volumes of space, would entail that they would be entangled. Entanglement entails some kind of method for the various copies in different Hubble volumes to be able to communicate information with each other nearly instantaneously, regardless of the vastness of the intervening distance. I here propose a solution that has already been proposed by others: namely, that tiny wormholes could connect entangled particles. This conjecture has been termed the ER=EPR model. Here, I put it into the context of the quantum/cosmological-combined multiverse model. In this model, these tiny wormholes would connect different versions of an object in different universes, allowing quantum entanglement to exist between them.

I take it a step further, and propose another, more controversial idea; combining retrocausality and backwards time travel with the ER=EPR model. Other experiments have hypothesized that quantum entanglement could be explained by signals traveling backwards in time to a time when the two entangled particles were closer together, and could thus transmit information easily. I find this an elegant solution, as, even with the addition of the tiny wormholes, the action could not be instantaneous--as nothing can travel faster than the speed of light, all travel through a wormhole would do is considerably shorten the journey needed to be taken by a signal from one particle to reach the other, but that would still only shorten the journey, not make it instantaneous, as is observed in quantum entanglement. Allowing backward causation would explain this seemingly instantaneous action at a distance, as, then, the connection would have already been made in the past, prior to the measurements being performed on the entangled particles.

I propose that, in a standard quantum mechanical experiment described by the Schrödinger equation and its wavefunction, the probabilistic superposition of states represents all of the versions of a particle existing in different Hubble volumes, separated by vast expanses of space. They are, therefore, entangled. These entangled particles would be able to transmit information between each other, and, thus, have the ability to be instantly affected by measurements performed upon their counterparts. A possible explanation for their entanglement is that they are connected by miniature wormholes, which connect back in time to a time period in the past, perhaps very early on in the universe's history, shortly after the Big Bang, when these particles, or the matter that would later go on to become them, were situated close enough to each other that normal signal transmission between them could occur easily. This would mean that the connection between them could be maintained, as, no matter how far apart the particles would have drifted, the signal could always go back to a time when they were close enough through a miniscule wormhole. After a signal from one particle is sent through the wormhole back in time to the other particle in the past, perhaps the other particle could subsequently retain the information from the signal as it travels into the future, meaning that, by the time it is separated by the vast expanses of space between Hubble volumes that not even light has yet been able to traverse, it would retain information about its -- now quite far-away -- counterpart.

My new model combines the Many Worlds Interpretation of quantum mechanics, the multiverse model containing numerous Hubble volumes, the ER=EPR model of tiny wormholes linking quantum-entangled particles, and retrocausality & backwards time travel into one model that I feel comprehensively explicates both many of the mysteries of quantum mechanics, including probabilities, superpositions, and entanglement, as well as the mysteries of the multiverses.

This hypothesis of mine is by no means confirmed, and is still tentative, but I can only hope that further discoveries and experimentally-obtained evidence in the future might, perhaps, be able to corroborate it. Any constructive criticism or suggestions for improving this model, which I term the Quantum Hubble Volumes Temporal Wormhole Model, would be highly appreciated.

Saturday, March 18, 2017

In Response To Michael L. Woodruff On Bacterial Sentience

Michael L. Woodruff wrote and published an article in the journal Animal Sentience criticizing the idea that sentience exists in bacteria. Woodruff cites two reasons: first, that the processes often cited as showcasing bacterial sentience are not homologous to those thought to control sentience in multicellular neuronal organisms, and second, that aforementioned processes can be explained in terms of purely biochemical interactions, with no need to invoke sentience as an explanation for them. Here, I will respond to both of Woodruff's arguments.

The objection is raised that the genes coding for the chemotaxis system of bacteria are different from those coding for biological sensitivity in multicellular organisms with nervous systems. The bacterial chemotactic systemic genes "do not demonstrate broad species continuity". I fail to see how this has any bearing at all on the question of sentience in bacteria. Convergent evolution is a well-known phenomenon in organismic biology, so why can't it apply to sentience, as well? Why couldn't bacteria and multicellular, neuronal organisms have independently evolved sentience, from different genes?

Woodruff then states that, as the chemotaxis process in bacteria is carried out by a series of biochemical processes and interactions, it is unnecessary to "admit sentience as an explanatory variable to explain" it. But is this not true of even human neurological processes and interactions? After all, is not the indubitably sentient decision, by a human, to open a door merely sensory nerves in the skin communicating with neurons in the brain, and those neurons in the brain then communicating with muscles in the hand, using action potentials (electrical signals) and chemical neurotransmitters? The process of a human opening a door involves touch nerve receptors, which communicate the touch to the brain, which then sends a signal to the muscles in the hand to open the door. Likewise, ligands (chemicals that bond to other chemicals) in a bacterium's environment are sensed by the externally-protruding domains of its sensory proteins, which sends a chemical signal – a protein termed CheY – to bind to a rotor of the flagellum, and, thus, control the flagellar, and, in turn, the bacterium's, direction of motion.

After all, even in humans, such processes as thought and emotion are thought to be mediated by neurotransmitters, including dopamine and glutamate, and electrical signals. One could easily invoke Occam's Razor to claim that human behaviour, being, as it is, controlled by the transmission of electrical and chemical signals between neurons, can be sufficiently explicated without inferring the presence of sentience. Just as a human opening a door occurs through neurons in the hand, after sensing the environment, sending electrical signals and chemicals to the brain, which then sends those aforementioned signals to the muscles in the hand, ordering them to move and open the door, likewise, a bacterium's tumbling occurs through external sensory protein domains, after sensing the environment, sending a CheW chemical signal to the CheA protein, which, in turn, sends a CheY chemical signal, across the cytoplasm, to the protein that controls the direction of rotation of the flagellum, FLiM. Once CheY binds to the flagellar rotor, it induces the bacterium to tumble and to change its direction of motion. Notice the similarities? In both the human's case and the bacterium's case, the actions of opening a door and reversing swimming direction, respectively, can be adequately and satisfactorily explained with molecular processes and signal transmissions. What Woodruff said about the bacterium's case applies just as well to the human's case.

In both cases, however, there still lies the question of "why?" Why, in the human's case, did the brain, after processing the information about the external environment from the sensory nerves, decide to send signals to the muscles telling them to move? And why, in the bacterium's case, did CheA, after receiving the information about the external environment from the sensory protein domains, decide to send CheY to the flagellum, instructing it to modify its direction of movement? I propose, here, that, in both organisms' cases, the fact that a decision to initiate a behavior was made upon retrieval of and processing of cues from the external environment could, perhaps, be indicative of conscious sentience being a factor in the neurotransmitter and action potential-mediated interneuronal interactions of multicellular neuronal organisms, as well as the chemical and enzyme-mediated intermolecular interactions of unicellular organisms, respectively.

Bibliography:
Woodruff, Michael L. (2016) "Bacteria and the cellular basis of consciousness: Commentary on Reber on Origins of Mind". Animal Sentience, 126. (http://animalstudiesrepository.org/cgi/viewcontent.cgi?article=1152&context=animsent/)

Friday, March 17, 2017

Sasquatch Habitat And Population Size: Some Calculations

While I wrote an article that was skeptical about Sasquatches, as well as Yetis, quite recently, by no means does that entail that I blindly accept all arguments offered by skeptics against the existence of these creatures. One argument that I have been thinking about lately is the argument that, as large mammals require a large home range that is proportional to their body mass, and there is little forest habitat in the Pacific Northwest of Northwestern North America, this means that Sasquatch would have either been discovered long ago, or does not exist, as there is not sufficient forest to allow a breeding population of these creatures to remain hidden until now. This has spurred me to carry out my own calculations to determine how capable the forest habitat of the Pacific Northwest really is of supporting a viable breeding population of these hypothetical animals. Never content to just accept whatever information I read without subjecting it to some critical analysis and skeptical scientific scrutiny, I decided to test this claim made by critics of Sasquatch's putative existence.

The correlation between an animal's body mass and the size of its home range is furnished by the following formula: Home Range = 0.024 * Body Mass^1.38. I was not able to find, in any sources, the answer to the question nagging me: Does this formula refer to the kilometers and kilograms of the metric system, or to the miles and pounds of the imperial system? In any case, as miles are larger than kilometers and pounds are smaller than kilograms, utilizing miles and pounds would have the effect that the area of the home range would be represented by a smaller number, and the mass of the animal would be represented by a larger number. Therefore, this would make the calculated plausibility of Sasquatch lower than if kilometers and kilograms had been utilized in their stead.

Since I am trying to stay as conservative and critical as I can possibly be (for reasons I will state at the end of this post), I decided to plug in the numbers that would render it the least likely that a viable Sasquatch population could exist in the Pacific Northwest, meaning that I decided to use miles and pounds as units. Additionally, while there are varying hypothetical speculations about the body mass of Sasquatch in the literature, I decided to go with 1,000 pounds, reportedly the highest end of the range, according to a Bigfoot research group.

Meanwhile, according to the World Wildlife Fund, also known as the Worldwide Fund For Nature, there are 114,000 square miles of forest in the Pacific Northwest.

I then plugged 1,000 pounds and 114,000 square miles into the equation relating home range to body mass:

HR = 0.0024 x 1,000^1.38
1,000^1.38 = 13,803.8426
HR = 0.0024 x 13,803.8426

HR = 331.29222 m.^2

So I got the result that the home range for one 1,000-pound Sasquatch would be 331.29222 square miles.

Then, I divided this number by the estimated number of square miles of forest in the Pacific Northwest, about 114,000 miles, to get the estimated population of Sasquatches that could inhabit this region.

Pop. = 114,000/331.29222
Pop. = 344.1070826 individuals

My calculated result was that there is a population of about 344 Sasquatches in the Pacific Northwest. Now the question arises: Is even this estimate, which I tried to lowball as much as I could, enough to constitute a viable breeding population of animals? Well, considering the fact that many species and subspecies of large-bodied mammals are currently so endangered that their populations are far smaller than this estimate, the South China Tiger offering just one example, I would say yes. Indeed, according to the Encyclopedia Britannica, a general rule of thumb is that 50 is a minimum number of individuals needed for a genetically viable breeding population. Sasquatch, according to my calculations, would be well over 300 individuals. Whether or not that population is large enough to furnish enough genetic diversity to sustain the population for long periods of time into the future in a world in which the effects of human activity run rampant throughout the biosphere is a different story. Indeed, if Sasquatch exists, it may be that their population was once higher in the past, and has now declined as a result of human encroachment onto their habitats, in which case, if it is ever discovered, it would likely be classified as an endangered species and enjoy the full protection of the law.

And now I come to the reason why I intentionally tried to lowball the estimates as much as I could. And that is to demonstrate that, even in the "worst-case" scenario for Sasquatch's existence/"best-case" scenario for its non-existence, the calculations would still permit a viable breeding population of Sasquatches to exist in the Pacific Northwest of North America. It may very well be that Sasquatch weighs far less than 1,000 pounds, or that this formula is in the context of using metric units of measure, rather than imperial ones (indeed, considering that metric units tend to be far more often utilized as the standard units of measure in the sciences, I think the latter is actually quite likely).

Now, keeping the body mass of the animal constant, I will calculate the estimated viable population size using the aforementioned metric units. In metric units, 1,000 pounds gets converted to 453,592 kilograms, while 114,000 square miles gets converted into 295,258.645 square kilometers.

HR = 0.024 x 453.592^1.38
453.592^138 = 4,636.585077
HR = 0.024 x 4,636.585077
HR = 111.27804185 km.^2

Now, I, once again, divide this number by the area of forests in the Pacific Northwest to get an estimated viable population size.

Pop. = 295,258.645/111.27804185
Pop. = 2,653.3414867 individuals

See how much of a difference that made? Now we have a population of over 2,000 individuals, close to 3,000. This is roughly comparable to what is thought to be the population of remaining wild tigers in the entire world.

So, to recap: Am I a believer in Bigfoot? No. I do not have belief or faith in cryptids, and I go where my evidence, calculations, and logic lead me. And my calculations lead me to the conclusion that, despite the paucity of scientific evidence that withstands the scientific criteria for proving the existence of a given species beyond reasonable doubt, the argument against the possible existence of these creatures from the ecological body size to home range ratio can be safely ruled out.

References/Works Cited:
• du Toit, J.T. December 1990. "Home range – body mass relations: a field study on African browsing ruminants". Oecologia. http://link.springer.com/article/10.1007/BF00319416
• Vath, Carrie L. and Robinson, Scott K. 9 December 2015. "Minimum viable population (MVP)". Encyclopedia Britannica. https://www.britannica.com/science/minimum-viable-population
• Parker, Edward. "Pacific Temperate Rainforests". World Wildlife Fund/Worldwide Fund For Nature.  http://wwf.panda.org/about_our_earth/ecoregions/pacific_temperate_rainforests.cfm

Saturday, March 4, 2017

A "Nanobrain" For Unicellular Organisms Via A System Of Interconnected Signal-Transducing Proteins


I mentioned earlier that some studies are starting to show evidence of cognition in unicellular organisms, including slime molds and bacteria, that lack brains or nervous systems. However, there perhaps exists an alternative plausible mechanism explaining how these attributes could exist in these brainless creatures.

This is the fact that, in every unicellular organism, the transmission of signals between components within the cell occurs regularly. There is a network of proteins that constitute the medium through which these signals are conveyed, with each protein assuming the same role as a neuron in an organism with a nervous system, and the ends of proteins, referred to as structural domains, assuming the same role as the ends of neurons, with both the structural domains of proteins and the ends of neurons transmitting and receiving signals to and from other proteins and neurons, respectively.

We know that the phenomenon of convergent evolution, in which different biological approaches to the same function arise in disparate taxa, is a common aspect of the evolutionary landscape. I find it plausible that a system of proteins through which signal transuction occurs, forming the equivalent of a "nanobrain" which is analagous to the brains of multicellular organisms, has allowed unicellular microorganisms to evolve the same functions of cognition, communication, and possibly consciousness, sentience, and self-awareness, as well as multicellular neuronal organisms.

References:
Marks, Friedrichs; Klingmüller, Ursula; Müller-Decker, Karen. Cellular Signal Processing: An Introduction to the Molecular Mechanisms of Signal Transduction. Garland Science, Taylor and Francis Group, LLC. Print. (https://books.google.com/books?id=0TIWBAAAQBAJ&printsec=frontcover&dq=cell+signal+transduction&hl=en&sa=X&ved=0ahUKEwi1sJbzgr7SAhVJz2MKHVu-BLMQ6AEIMjAF#v=onepage&q&f=false)

No, Tetragametic Chimerism Poses No Threat To The Individuality Of Early Embryos

In addition to the twinning argument, one additional argument sometimes utilized to deny the individuality of early embryos is the fact that two embryos are capable of fusing together to form a single organism. This process is known as tetragametic chimerism, and the resulting individual is referred to as a tetragametic chimera, or simply a chimera. They are called tetragametic because they originated from four gametes, twice the number as someone who is not a chimera.

The argument asserts that, as two embryos have the potential to become one individual, this means that, before fusion, each embryo cannot be regarded as a single individual in its own right. However, I find this argument to be as jejune and flawed as the twinning objection, and I will elucidate why I think so.

Just like how I mentioned that the twinning argument is rendered absurd by the fact that any adult animal could potentially be cloned, which is basically delayed monozygotic twinning, and, in fact, has even been referred to as such in the peer-reviewed scientific literature, as shown in the example cited below, I think that the chimerism argument is rendered absurd by the fact that organ transplants between adult animals are, in fact, not just theoretically possible, but already happen quite routinely.

As a hypothetical gedankenexperiment, let us envision a scenario wherein half of one adult human's organs are defective, and urgently need to be replaced. Now let us say that half of the organs from another adult human's body are removed, killing the unfortunate donor in the process, and transplanted into the recipient, with the result that the recipient now has half of the organs in their body originating from someone else, and comprised of cells with a different genome, rendering them a postnatally-derived tetragametic chimera.
In this scenario, no one would deny that, prior to the fusion, there existed two distinct individual adult organisms. Likewise, the same would hold when this process occurs involving a pair of early embryos coalescing into a singleton.

While, for ethical reasons, such a scenario is obviously unlikely to happen, it still means that, at least in principle, it is possible to form tetragametic chimeras in adulthood via the process of organ transplantation, just as, at least in principle, it is possible to form monozygotic twins in adulthood via the process of cloning.

Therefore, just as the fact that cloning is hypothetically possible at any age of postnatal life renders the argument that the ability of a single embryo to split into twins during the process of monozygotic twinning means it is not yet an individual absurd, so, too, does the fact that extensive organ transplantation is hypothetically possible at any age of postnatal life render the argument that the ability of more than one embryo to combine into one during the process of tetragametic chimerism means that neither are yet individuals absurd.

References:
Med Wieku Rozwoj. "Human clone or a delayed twin?" 2001;5(1 Suppl 1):39-43. (https://www.ncbi.nlm.nih.gov/m/pubmed/11684762/)


Saturday, February 25, 2017

A Review Of The Nessie Chapter In Abominable Science!: Origins of the Yeti, Nessie, and other famous cryptids by Daniel Loxton and Donald R. Prothero

I just finished reading the chapter about the Loch Ness Monster in the skeptical cryptozoology book Abominable Science! by Daniel Loxton and Donald R. Prothero. I will review it here.

Overall, the chapter makes a decent analysis of several of the evidence marshaled to support the existence of the Loch Ness cryptid, including the Surgeon's Photo taken by Dr. Robert Kenneth Wilson, who was really a gynaecologist, rather than a surgeon, but, hey, I guess most people don't think of the Loch Ness Monster, but something else entirely, when they hear the phrase "Gynaecologist's Photo". I agree with the chapter's conclusions that the Surgeon's Photo is likely to be a hoax, although I am still open to the possibility that it shows either a bird or an otter, as well as the same conclusion with regard to the Stuart Photo. I should note that when I first set eyes on both of these pictures as a child, they looked off to me, in some way. I suppose my intuition wasn't too far off the mark.

I also found the connection drawn between King Kong and the sighting by the Spicers enlightening, and I am inclined to think that this is quite a plausible suggestion. I think it is quite plausible that the release of the movie King Kong created an atmosphere during the time of the Great Depression which made prospective witnesses more likely to interpret sightings of common animals and disturbances of water in the loch in the light of the film, causing it to morph into a sauropod- or plesiosaur-like entity. I might opine here that the Spicer sighting could have been a group of otters seen crossing the road, which they interpreted as a sauropod-like beast since they might have been driving home groggily after seeing the movie.

These are the good parts of this chapter, in my opinion. Overall, I found the analysis of evidence, such as photos and videos, to be mostly rational and cogent, with one exception. The digital enhancement of the Rines flipper photograph was emphasized, and the original, unenhanced version was shown next to the enhanced version, in an attempt to show how a plesiosaur-like flipper was detectable in the enhanced version, but not in the unenhanced version. However, with me, this juxtaposition of the images had the exact opposite effect as that which was intended. Indeed, I could still clearly make out the shape of a flipper, even in the original, unenhanced version, and it is much too clear to me, I think, to be a case of pareidolia on my part.

But when it came to the evaluation of the plesiosaur hypothesis and the possible entry of prospective Nessies into the loch from the ocean, I was left somewhat disappointed. I did not find the argument put forth against a plesiosaur identity being a possible one for a prospective unknown creature in Loch Ness convincing. This is because the argument overlooked key fossil finds and paleontological studies, overlooked possibilities for plesiosaur behavior and physiology which seem plausible in light of those of relatives known to be extant, and flatly contradicted other portions of the same chapter on the issue of entry into Loch Ness from the sea.

It is stated that "They [plesiosaurs] were tropical animals, unsuited for the cold waters of the loch—and most plesiosaurs were marine animals, unsuited for freshwater in general". Yet a study published three years prior to this book found evidence that plesiosaurs likely were in possession of endothermy, colloquially referred to as "warm-bloodedness". And the claim that plesiosaurs were "tropical animals" is just false. Indeed, plesiosaur fossils have been found in several Upper Cretaceous formations in Antarctica. And while it is true that Antarctica in the Upper Cretaceous was warmer than it is today, it still had a climate not too dissimilar to Southern South America today, as one article covering an Antarctic plesiosaur fossil find noted. Considering the southern tip of South America, Tierra del Fuego, lies at a latitude that is more southerly than Loch Ness is northerly, I doubt that a plesiosaur adapted to the cold climate of Late Cretaceous Antarctic waters would have much difficulty adapting to the cold climate of Holocene Loch Ness waters.

And plesiosaur fossils have also been found in regions indicative of them having lived in a freshwater environment. Indeed, considering that numerous modern species which spend some or much of their life in marine environments, ranging from seals to cetaceans to Bull sharks to both saltwater crocodiles (Crocodylus porosus) and American crocodiles (Crocodylus acutus), have been known to inhabit freshwater environments, as well as saltwater environments, it seems rather dogmatic to me to state that plesiosaurs could not have done the same.

It is also stated that "Finally, plesiosaurs were air breathers. Any plesiosaurs in Loch Ness could be photographed several times an hour, each time they surfaced to breathe." This argument is stating that, as plesiosaurs were air-breathers, they would be regularly seen far more often breaking the surface of the water to take a breathe, rendering it unlikely that they would be able to remain inconspicuous for long in a lake such as Loch Ness. However, the idea has been previously brought forth that plesiosaurs might have evolved snorkel-like appendages on their heads that they might protrude above the surface of the water to take a breathe, which would not be as conspicuous. And while it is argued  that such snorkels would, nevertheless, still be detected, another option awaits in the wings. And that is the aquatic cutaneous diffusion method of respiration.

Whether plesiosaurs were entirely air-breathers, or whether they respired through water, is not something that can be directly ascertained from the fossil evidence at hand. It is, in fact, entirely plausible that plesiosaurs could have been able to supplement their oxygen intake by aquatic cutaneous diffusion of oxygen -- i.e., absorbing molecules of oxygen directly from the water through their skin. Indeed, some turtles are known to respire in this way nowadays, and it is worth noting that, additionally, all humans once respired in this manner, as well, in utero, prior to their birth. If plesiosaurs were able to respire in such a manner, it would render them far more adapted to an aquatic lifestyle and ecological niche. Indeed, considering that extant turtles, which are less aquatic than plesiosaurs probably were (there is evidence that plesiosaurs were viviparous, giving birth at sea, constituting evidence that they were supremely adapted to a nearly completely aquatic existence), have evolved this ability, it would be surprising if plesiosaurs did not, likewise, do the same. A plesiosaur respiring through water via cutaneous diffusion of oxygen would not have a pressing or urgent need to routinely come to the surface to breathe air, meaning that it could conceivably remain hidden in a freshwater lake for a long stretch of time.

When discussing possible entry of the unidentified animals into Loch Ness from the ocean, it is stated, as well, that "The rivers and canals that flow into Loch Ness can be confidently ruled out as commuter routes for large monsters, broken up by shipping locks, or some combination." While it is true that, past a certain upper limit on size, an oceangoing creature would encounter considerable difficulty in navigating these pathways to the loch, it is worth noting that it is a confirmed fact that animals as substantially-sized as seals and porpoises have managed to do so. Indeed, it strikes me as rather perplexing that the author(s) spent so much of the rest of the chapter emphasizing the fact that these known marine animals have been known to make their way into Loch Ness previously with the purpose of using their presence in the loch to explain Nessie sightings. So why the double standard here? If porpoises and seals can swim into Loch Ness from the Moray Firth through the River Ness or the Caledonian Canal, why not putative Nessies, as well?

The statement about "large monsters" not being able to enter the loch is a red herring, as it is by no means a prerequisite that the creatures must already be large at the time that they enter the loch. The creatures could have made their way into the loch from the ocean when they were juveniles, perhaps no larger than salmon, or even smaller, and remained in the loch until they grew larger, rendering them trapped in the loch.

Indeed, this allows me to segue into another issue brought up in this chapter, that of the need to maintain a breeding population of creatures in the loch for eons. It is asserted that, to have a population large enough to breed, it would necessarily follow that there would not be enough food in the loch to sustain them, and the population would be too large for them to be able to remain hidden.

However, it is entirely possible that, rather than a breeding population of creatures having been extant in Loch Ness since the end of the Pleistocene, occasional vagrants have navigated their way into the loch from the ocean, and remained trapped there for a generation or two, before dying out. This would have the additional advantage of explaining why sightings seem to pique in some years in comparison with others. This hypothesis has come to be referred to as the 'Rogue Nessie' hypothesis, and it is covered delightfully well by writer Kurt Burchfiel in this article for StrangeMag magazine: http://www.strangemag.com/roguenessie.html

Finally, it is stated repeatedly that there were no sightings of a strange, unidentified creature in the same vein as Nessie at Loch Ness prior to the 1930s in the decimal Gregorian calendar. Yet this, too, is demonstrably false. Indeed, a newspaper report from the 19th century of the decimal Gregorian calendar reporting on a sighting of what seemed to the locals to be an anomalous large fish in Loch Ness stated that the locals had been inclined to think of the existence of such a besst in the loch as a reality for years, indicating that there was already a tradition of reported sightings of strange creatures in Loch Ness by this time.
And, even if it were true that Nessie sightings made their debut in the 1930s, this would not be a big deal, as, with the Rogue Nessie hypothesis, which postulates that Nessie is an oceangoing creature which occasionally swims into the loch from the open ocean, it is entirely plausible that a small population of these creatures could have entered the loch for the first time in the 1930s.

Overall, the chapter on Nessie, the Loch Ness Monster, the fourth chapter of Abominable Science!, contributes a decent analysis of much of the evidence purported to support this alleged cryptid, while having some deficiencies in the theoretical realms, in particular, when it comes to the arguments presented against a plesiosaur identity for Nessie and those presented against the creatures being able to remain undiscovered in Loch Ness.

The truth is that the palaeontological evidence from peer-reviewed scientific journals is, at worst, indifferent to the question of whether or not a plesiosaur identity is plausible for lake monsters in general, and the Rogue Nessie hypothesis shows that the objections with regard to population size and detectability can be surmounted by certain scenarios, the plausibility of which has been borne out by documented cases of marine animals making the switch to freshwater habitats.

It is worth noting at this juncture that all of the evidence and reasoning presented here applies to most reported lake cryptids, such as Champ of Lake Champlain, Ogopogo of Lake Okanagan, Storsjoodjuret or Storsie of Lake Storsjon, Selma of Lake Seljordsvatnet or Lake Seljord, Nahuelito of Lake Nahuel Huapi, etc.

References/External Links:

Endothermy in Plesiosaurs:
http://science.sciencemag.org/content/328/5984/1379
http://news.nationalgeographic.com/news/2010/06/100610-giant-sea-reptiles-warm-blooded-science/


Polar Plesiosaurs:
http://www.bioone.org/doi/abs/10.1671/0272-4634(2003)23%5B104%3ATEPACF%5D2.0.CO%3B2
http://www.nature.com/news/2006/061211/full/news061211-4.html

Freshwater Plesiosaurs:
http://www.tandfonline.com/doi/full/10.1080/14772019.2011.634444?scroll=top&needAccess=true

Saturday, February 18, 2017

An Additional Note On Monozygotic Twinning And Individuality In Embryos

I mentioned earlier that it now appears that, when monozygotic twinning occurs, an original embryo is formed at time of egg-sperm fusion, and then some of its cells break off at the blastula stage to form a second embryo, while the original embryo continues to exist, and can regenerate its missing cells.

Even if this picture turns out to be erroneous, and it turns out that monozygotic twinning erases the existence of the original embryo, and leaves two new embryos in its wake, this would still not prove that, before the twinning event occurred, there was not one individual embryo.

As an analogy to help demonstrate this clearly, let us consider the fact that, in principle, every single cell could be taken from an adult animal, such as an adult human's, body and a clone made from each one of them. This would have the result that there would be trillions of clones of the original adult, while the original adult would cease to exist. But by no means does this, somehow, retroactively negate the existence of the original adult as one individual organism, as opposed to merely a not-yet-individuated clump of cells, prior to its dismantlement and concurrent cloning.

When it is realized that, in any case, regardless of what happens to the original embryo when it splits to form identical twins, triplets, quadruplets, etcetera in the monozygotic twinning process, the exact same process could theoretically happen to an adult, as well, the legitimacy of this argument against the individuality of early embryos during the stage in which monozygotic twinning is possible gets effectively flushed down the toilet.

Cryptozoology And The Whole Science Vs. Pseudoscience Debacle

It is often claimed that cryptozoology is a pseudoscience. I have written on this topic before, but I feel the need to do so once more right now, as I have encountered arguments that have made me come to realize that it would be germane of me to do so.

First, we need to define "science" and "pseudoscience". Science is a means of obtaining information by formulating ideas called hypotheses, testing them to see whether or not they match the reality at hand, and keeping or discarding them based on how well they conform to the physical evidence at hand. This process should usually be able to be repeated by others. Pseudoscience is something that has a superficial veneer of being scientific, but does not meet the key criteria of being scientific. While it is still somewhat debated what those criteria are, the two dominant schools of thought are the logical positivist, or verificationist, philosophy of science, and the falsificationist philosophy of science, particularly the latter. Verificationism means that a hypothesis needs to be able to be proven, or verified, by obtaining sufficient evidence for it to be scientific, while falsificationism means that a hypothesis needs to be able to be disproven, or falsified, by obtaining sufficient evidence against it to be scientific.

Cryptozoological assertions meet both of those criteria. If I assert that "a large undiscovered hominoid species is inhabiting North America", this could potentially be verified by finding a body of this hypothetical unknown hominoid. Meanwhile, it could also potentially be falsified by painstakingly searching every square centimeter of North America and failing to find one scrap of evidence, one measly little body part, to support the assertion.

There is the issue that many self-proclaimed cryptozoologists insert intrinsically unfalsifiable supernatural assertions into the field, such as asserting that a given cryptid is a noncorporeal entity, such as a ghost or a phantom. Indeed, critics of cryptozoology often use the ubiquity of such supernatural-seeming reports of cryptids in the archives of cryptozoology to imply that the cryptids in question are inherently connected to the supernatural, and, thus, it makes sense to lump in cryptozoology with the study of paranormal phenomena, such as parapsychology. Yet this is a grave error. This is because many known animals have been associated with supernatural phenomena, as well, just as frequently, if not more so, than cryptids. From superstitions of black cats being associated with bad luck to reports of spectral hounds to reports of cows being abducted by aliens, all of the same criticisms that are leveled at reported hypothetical unknown species investigated by cryptozoology could equally be applied to known species whose existence is unquestioned, and, thus, render the entire field of zoology pseudoscientific due to its association with the supernatural.

So cryptozoology deals in hypotheses that are potentially both verifiable and falsifiable, and the association of the reported creatures it investigates with the supernatural does not render it pseudoscientific any more so than the association of other, known animals with the supernatural renders "mainstream" zoology pseudoscientific.

One more argument commonly leveled in favor of classifying cryptozoology as a pseudoscience is that it has not had any successes thus far. While this statement is certainly questionable, and, indeed, I highly doubt its veracity and deem it untrue, even assuming that it was true, this would not render cryptozoology a pseudoscience any more than the fact that no extraterrestrial life has yet been discovered outside of Earth renders astrobiology (the study of life, including extraterrestrial life, throughout the Universe) a pseudoscience. Indeed, many of the same claims regarding cryptozoology being pseudoscientific could equally be applied to astrobiology. Yet astrobiology is widely recognized as a legitimate branch of biology, as opposed to a pseudoscience. So what gives? Why the apparent double standard here?

I honestly think the reason as to why cryptozoology is widely panned as pseudoscientific is because it has been marred by association with poorly-done versions of it that actually are pseudoscientific in the popular media. From true believers who fail to think critically and investigate what evidence they think they have managed to obtain to those who assert a supernatural origin for certain cryptids, it is true that most of what masquerades as cryptozoology to much of the population is, indeed, pseudoscience. Much of the real scientific work going on in cryptozoology -- such as the peer-reviewed articles in the Journal of Cryptozoology, the studies of potentially undiscovered large marine species by Naish, Shanahan, and Paxton et al., the studies of reported Yeti hairs that found them to belong to bears by Bryan Sykes, Karl Shuker's books, The Cryptozoologicon, etc. -- is obscure, and does not receive as much attention as the pseudoscience that surrounds it.

As cryptozoology is not, inherently, pseudoscientific, by bringing the actual science going on in it to the forefront and drawing more attention to it, hopefully, its reputation among the scientific community can be salvaged, and serious scientific investigations of reported cryptids can occur on a wider scale than they currently are.

Wednesday, February 8, 2017

Epithelial Tissues: An Arbitrary & Artificial Grouping That Ought To Be Split Up

Epithelial Tissues: An Arbitrary & Artificial Grouping That Ought To Be Split Up

Histology is the study of the bodily tissues of organisms and their cellular structure. In histology, animal tissues are conventionally divided into no more than four main types: Muscle Tissues, Connective Tissues, Nervous Tissues, and Epithelial Tissues. Muscle Tissues constitute muscles, which allow an organism to move. Connective Tissues are tissues that connect body parts to other body parts, and include bone, cartilage, and blood. Nervous Tissues constitute the nervous system, including the brain, spinal cord, and peripheral nerves, and are utilized by organisms to sense and be cognizant of their environments. It is often asserted that these four tissue types are natural groupings that arise from common shared characteristics of the tissues grouped within them. While this appears to be the case for Muscle, Nervous, and possibly Connective Tissues, I think it is not true for Epithelial Tissues. I think Epithelial Tissues are an arbitrary and artificial grouping of several disparate tissue types that humans have lumped together, without good cytological or ontogenetic justification. This article will explore Epithelial Tissues in depth, and arrive at an explanation as to why I propose that this unnatural grouping ought to be split into several different tissue types.

To start out, it shall be noted that all tissues in an adult animal are ultimately derived from one of three original germ layers that develop in an embryo during a process known as gastrulation: the Ectoderm, the Mesoderm, and the Endoderm. If two or more tissues in the adult were derived from the same embryonic germ layer, then this furnishes a natural basis for them to be grouped together. Indeed, analogously to phylogeny, if two or more adult tissues share a common ancestor, so to speak, in an embryonic germ layer, this is the ontogenetic equivalent of sharing a common ancestor in phylogenetics, and, thus, provides good reason to group them together, with the resultant tissue group being the equivalent of a monophyletic group in phylogeny.

On the contrary, if two or more adult tissues do not derive from the same embryonic germ layer, then grouping them together would be analagous to grouping together two or more species that do not share a most recent common ancestor together in phylogeny, rendering the resultant group the equivalent of a polyphyletic group in phylogeny. A notable example of such a polyphyletic grouping is Pachydermata, including usually large mammals with thick skin such as rhinoceroses, hippopotamuses, and elephants. Pachydermata, as a group, has now been abandoned by those who study the phylogenetic relationships of these mammals, as it has now been demonstrated that elephants actually share a more recent common ancestor with manatees and hyraxes than with either of the other two, hippopotamuses share a more recent common ancestor with cetaceans than with either of the other two, and rhinoceroses share a more recent common ancestor with horses than with either of the other two.

Now here's the kicker. While all tissues classified as Muscle Tissues are derived from the mesoderm, all tissues classified as Connective Tissues are, likewise, derived from the mesoderm, and all tissues classified as Nervous Tissues are derived from the ectoderm, tissues classified as Epithelial Tissues are derived from all three of the germ layers, endoderm, mesoderm, and ectoderm, with different subcategories of Epithelial Tissues being derived from different germ layers. This makes Epithelial Tissues analogous to a polyphyletic phylogenetic grouping, such as Pachydermata. Just as polyphyletic groupings have now largely fallen by the wayside in favor of the more natural monophyletic groupings in taxonomy, likewise, it makes sense for groupings naturally derived from shared ontogenetic provenance from one of the embryonic germ layers to take precedence over artificially-derived arbitrary groupings of disparate tissues from different embryonic germ layers in histology.

Additionally, it shall be noted that at least Nervous Tissues and Muscle Tissues share common aspects of physical appearance. For example, although the exact specifications may vary between different locations in the nervous system, all Nervous Tissues are composed of the same type of cells, neurons. Meanwhile, while there is variation between striated, smooth, and cardiac types of muscles, all muscle tissue, likewise, is comprised of cells that have an appearance and structure that is, overall, mostly similar.

The same cannot be said for Epithelial Tissues. There are numerous variegated types of Epithelial Tissues, and the cells present wildly varying morphologies. Epithelial Tissues are currently divided into seven subcategories based upon the shape and configuration of their constituent cells: simple squamous, simple cuboidal, simple columnar, stratified squamous, stratified cuboidal, pseudostratified columnar, and transitional. As shown in the juxtapositions of Figure I, Figure II, and Figure III below, these different subcategories of Epithelial Tissues look vastly different, as opposed to the subcategories of Muscle Tissues and Nervous Tissues, which, overall, present a pretty similar appearance.

Additionally, unlike Muscle Tissues, which are all universally internal, and Nervous Tissues, which are all universally internal, as well, Epithelial Tissues are found both externally and internally. The tissue on such widely separated locations in the body as the epidermis of the skin and the lining of the gastrointestinal tract is said to consist of Epithelial Tissues, for example. An often-asserted commonality shared by all Epithelial Tissues is that their job is to protect the body from external substances in the environment. However, this seems like a rather arbitrarily-chosen criterion to me. For example, adipose tissue, or fat, is classified as one of the Connective Tissues, yet it also plays a role in protecting the body from various putative threats in the environment, including trauma from impacts and cold, to name two. Yet it is classified among the Connective Tissues, rather than among the Epithelial Tissues. This shows that this shared characteristic of function is not enough to group the widely differing varieties of tissues grouped under the name of Epithelial Tissues into such a broad, overarching category.

Overall, to recap, Epithelial Tissues are derived from all three of the embryonic germ layers, meaning that they lack common ontogenetic provenance, unlike the other principal tissue types, they present a wide variety of cell structures and configurations, unlike the other principal tissue types, and the proposed criterion of common function is not enough to salvage the grouping, as, if applied logically and consistently, this same criterion would subsume other tissues that are not classified as Epithelial Tissues into the category, as well.

This is why I propose that, since Epithelial Tissues seem to me to be an arbitrary and artificial grouping of several unrelated tissues together by humans, it would be beneficial for histology to drop this grouping, and split it into several different groupings, with the result that there would be more than four principal types of tissues present in animals' bodies, just as phylogeneticists have now dropped arbitrary, artificial polyphyletic groupings in favor of natural monophyletic groupings.




Fig. I: The three primary types of neurons, cells that constitute what is classified as Nervous Tissue.




Fig. II: The three types of Muscle Tissue and their characteristics and functions.





Fig. III: The seven recognized types of tissue currently classified under the label of "Epithelial Tissues", and the characteristic shapes of the cells that comprise them.

Friday, February 3, 2017

Why Time Travel Does Not Violate The First Law Of Thermodynamics

Time Travel And Conservation Of Energy/Mass/Matter:

The possibility of time travel, particularly to the past, has had numerous objections raised to it over time. Perhaps one of the most seemingly difficult to grasp is the objection that time travel, particularly to the past, violates the First Law of Thermodynamics, also known as the Law of Conservation of Energy and Mass/Matter (as energy and mass are equivalent, as shown by Albert Einstein's famous equation e=mc^2). This law states that energy can never be created nor destroyed, but can only be changed from one form to another. The reason some have equated this to ruling out time travel is the following: You are probably aware that you existed in the past, for example, one week ago. Even prior to your conception, although you were not alive, the particles that would later make up your body still existed, but were just scattered around in various places until they later coalesced to form you. So every person comes from matter that already existed, and has since the beginning of the Universe. Let's say you time traveled to the Late Jurassic period. Even though it is at least 144 million years before your conception, the energy that would later constitute your body exists, as tiny particles scattered throughout the world (and possibly throughout the universe -- who knows if some of the particles that would later make up your body came to Earth from outer space?). This, according to some, constitutes a violation of the First Law of Thermodynamics, since you now coexist in the same time period alongside the particles in the past that would later form you, with the result that more energy is being added to the Late Jurassic, while energy is being simultaneously removed from the present Quaternary period, constituting a violation of conservation of energy.

This is the crux of the argument against time travel from violation of conservation of energy/mass. However, I disagree with this argument, and this article will refute this argument by probing more deeply into the logical underpinnings at work beneath it.

The Law of Conservation of Energy simply states that, in a closed system, energy cannot be created or destroyed. A closed system is defined as a system in which no input from outside of the system is received by said system. The issue at relevance here is that different time periods are emphatically, demonstrably not closed systems, due to the simple fact that entities are always, constantly moving forward in time, and, therefore, entering new time periods. Someone inevitably entered Wednesday from the preceding Tuesday; they did not just magically, spontaneously pop into existence on Wednesday. Additionally, general relativity shows that space and time are inextricably woven together, as complementary components of a single, unified system known as spacetime. Therefore, since individual time periods are not closed systems, we do not have to apply the conservation law to particular periods of time, on their own. Considering the entire spacetime continuum, altogether, to constitute a closed system, someone popping into a past time prior to their conception, and existing alongside the particles that would later make up the ovum and spermatozoon that would eventually conceive them, would not be injecting more mass or energy into a closed system, as, without time travel into the past, both the putative time traveller and the particles in the past prior to the individual's conception that would later come to constitute their body already are coexisting in the spacetime continuum -- merely at different times. Travel to the past would merely bring their locations in spacetime into greater proximity with one another, as they are now at the same time, instead of at differing times.

As a thought experiment, let us now envision a wormhole connecting the year 1733 to the year 1725, for example. A person conceived in 1721 who is twelve years old in 1733 and four years old in 1725 would exist in both time periods. Now let's say the twelve-year-old goes through the wormhole, and arrives back in time in 1725 from 1733. When this happens, the twelve-year-old disappears from 1733, and reappears in 1725. While, if we were to consider each of the times, 1733 and 1725, as closed systems, this would, indeed, be in violation of the First Law, since we know that they are not closed systems, we know that this is not a violation. If we are to consider the entire spacetime continuum, as a whole, to be a closed system, then, there is no violation of the First Law of Thermodynamics inherent in this situation, as the disappearance of the time traveller from 1733 is balanced out by his/her subsequent reappearance in 1725. It's just like how removing a peanut from a bag of peanuts does not violate the law of conservation of energy/mass, as the peanut bag is not a closed system, but, rather, part of a closed system. Energy/matter can, indeed, be displaced within a closed system. And being displaced is completely different from being destroyed or created.

Energy can be displaced from one region of a closed system and arrive at another region in its stead. There is, theoretically, no reason that a person could not coexist at the same time as the particles which would later go on to constitute their physique, instead of existing at a different time from them. Only the location of the person along the time dimension would have changed, without creating any new energy, so this would not violate the Law of Conservation of Energy, and, by extension, of Mass and of Matter.

Overall, this argument against time travel, particularly time travel to the past, seems compelling at first glance, but, upon closer examination, its faults become readily apparent. It shall be noted that one may feel tempted to accept arguments against the possibility of time travel due to the fact that time travel contradicts common sense. However, there are numerous statements made by science, some of which are facts, which contradict common sense. Common sense is not always necessarily an infallible arbiter of truth. One must always tread with caution, and think critically about any arguments one finds, and parse them logically, even if they seem to appeal to intuitive notions of common sense. This is how progress is made, and new discoveries that potentially overturn paradigms occur.

Tuesday, January 31, 2017

Consciousness, Sentience, And Self-Awareness: An Overview

Consciousness, sentience, and self-awareness are among the most contentious topics in biology, as well as in popular culture. In the past, it was commonly assumed by eminent philosophers that only humans were conscious and sentient, and no other animals, let alone non-animalian organisms, were. Additionally, even now, it is commonly believed that even some humans younger than a certain age, such as in the prenatal stages of life, are not capable of being in possession of these qualities. But a mass of scientific research, welling up to a profound crescendo which cannot be ignored, has been accumulating over the years that contradicts these assertions. No longer can we claim, while still remaining on solidly grounded scientific footing, that only postnatal Homo sapiens are conscious, sentient biological entities. In fact, one of the core assumptions accepted even by many in the scientific community now, that a brain, or, at the very least, a nervous system composed of neuronal cells, is necessary for consciousness, sentience, and self-awareness has now started to be persuasively challenged by the evidence. This is what is the primary focus of this present article.

Firstly, we need to define these terms. Consciousness can be defined as an awareness of one's surroundings, sentience can be defined as an ability to perceive subjective states (i.e., "This situation is good for me", "This situation is bad for me", etc.), and self-awareness can be defined as awareness that one exists, and recognition of oneself, as an individual, distinct from others. Based on these very simple criteria, it shall be shown that the widely-accepted assertion that only humans, and only humans at a certain ontogenetic stage, at that, possess these qualities is simply not concordant with the evidence at hand presently.

Let us start with the evidence from those creatures closest to home, so to speak, with members of the same species in which these qualities are accepted as existing, Homo sapiens, but at an ontogenetic stage where it is assumed not to possess them: neonatal and prenatal humans.

It is very common to encounter statements that a fetus is not conscious, sentient, or self-aware. Some even go as far as saying that a newborn baby, after birth, does not yet have those qualities. Yet a cursory overview of the scientific literature on this subject reveals these assertions to be grounded more in preconceived notions than on fact. A study has shown that newborn babies can recognize the sound of their own cry when heard among the sounds of other babies' cries and the sounds of other animals, revealing a type of self-awareness at the neonatal stage of life. And this is purely anecdotal, and thus cannot count as empirical scientific data, but one of my own cousins once removed, at six months after her birth, has, according to her parents, already developed a preoccupation with her own reflection in mirrors, a preoccupation which she does not display when observing the reflections of other objects in mirrors, an indication of an awareness of a sense of self.

A study by Umberto Castiello et al. has revealed that, at least as early as fourteen weeks in utero, twins have been observed touching each other. The first inclination of the reader would be to dismiss these motions as mere reflexes, but the authors point out that they seem purposeful and directed. This study examined five pairs of twins in utero, and all displayed this same behavior, with the authors therefore arriving at the conclusion that "These findings force us to predate the emergence of social behaviour".

Let us now move on to the likely even more controversial portion of this article, that concerned with the research indicating the existence of these qualities, as well as numerous other cognitive capabilities, such as problem-solving and communication, in creatures completely lacking brains or nervous systems as we know them, such as plants, protozoa, and bacteria.

Any mention of plant sentience, consciousness, or self-awareness is immediately marred by association with the pseudoscience that, sadly, cast a dark shadow over investigations into this subject decades ago, beginning with the publication of The Secret Life of Plants, a book which claimed that doing things to plants such as playing certain varieties of music to them would allow one to communicate telepathically with them and convey emotions, among other such mystical claims. This has led to the investigation of plant cognition being seen as taboo by serious botanists nowadays, a rather unfortunate reality, now that renewed research is beginning to show that this avenue of investigation is, indeed, worth pursuing.

The work of scientists such as Stefano Mancuso, Richard Karban, and Monica Gagliano on plant communication and learning has spread shockwaves throughout the botanical community, bringing up memories of the not-too-pleasant specter of the pseudoscientific claims engendered by The Secret Life of Plants and its ilk. Yet this research cannot be ignored. It has been shown by the work of Karban and Mancuso that plants are capable of communicating to each other through chemical signaling, with some even likening the chemicals released after grass is cut that give it such a characteristic smell as "screaming" intended to warn surrounding plants of the impending danger. Additionally, experimental research carried out by Gagliano has shown that some plants are capable of learning that a given stimulus is harmless after being exposed to it repeatedly, while giving a defensive reaction, showing that they still suspect it might be harmful, once subjected to a different stimulus.

This has led to the development of a nascent branch of botany known as plant neurobiology, which is a misnomer, as even the botanists who study it are aware that plants do not possess neurons, in the same way that animals do. While still an emerging field, it already has made promising progress, and many more insights into plant social behavior and cognition certainly await in the future.

Let us now move on to the organisms that are commonly thought to lie at the very bottom of the Scala Naturae of old, the microbes and protozoa. Even these seemingly most unlikely of candidates for the presence of consciousness, sentience, and self-awareness have no shortage of studies expounding the evidence for the presence of these qualities in them.

Some of the most persuasive evidence in this area has come from research on a certain species of Slime Mold, Physarum polycephalum. This slime mold has been shown to be capable of memorizing its history of spatial location, and of navigating a maze with such precision and ease that it would fill the most clever of human engineers with envy, as it would be comparable to their most carefully calculated efforts.

In addition, bacteria offer an impressive reportoire of cognitive and social behaviors. Bacteria are capable of processing input from their environments and producing outputs in return based upon their computation of said information. They also possess an ability known as quorum sensing. That is the ability to detect when a group of their own species has reached a sufficient number to be able to carry out a certain operation, implying some degree of social awareness. According to a study by the late Eshel Ben Jacob et al., bacteria display some cognizance of the distinction between themselves and others, i.e., self-awareness. Indeed, the actions of bacteria within the bodies of host organisms, and their ongoing battle waged with said host organisms' immune systems, has been compared in its complexity to human guerilla warfare. Bacteria are also capable of genetic engineering, incorporating foreign DNA into their own genomes. In other words, bacteria have had the ability to genetically engineer for billions of years, while humans have now had it for less than a century. This evidence is too impelling to be ignored. Renowned bacterial geneticist James A. Shapiro states that "This remarkable series of observations requires us to revise basic ideas about biological information processing and recognize that even the smallest cells are sentient beings."

I will be posting much more on this topic in the near future, but it shall suffice to say that we must be more open-minded about consciousness, sentience, and self-awareness in numerous varieties of creatures, from microbes to slime molds to plants, and, therefore, by extension, to zygotes, embryos, and fetuses of all animals.

Sunday, January 15, 2017

Sasquatches And Yetis: An Overview

Some of the most well-known alleged creatures investigated by cryptozoology are, undoubtedly, the supposed undiscovered bipedal primates reportedly seen around the world, including such fabled beasts as the Sasquatch, or Bigfoot, of North America, and the Yeti, or Abominable Snowman, of Asia. These alleged creatures are highly controversial, with their existence being widely regarded as unlikely by much of the scientific community, albeit with some notable exceptions, such as Grover Krantz and Jeffrey Meldrum. The proponents of their existence are quite zealous, passionately defending their supposed evidence against the arguments of the skeptics. In this article, I will examine this situation from a neutral perspective, arriving at a conclusion on this topic at the end, starting with an exercise in vicariously seeing what goes on in the minds of witnesses, from a first-person perspective:

I am walking through the dense, temperate rainforests of the Pacific Northwest, heading back to camp after collecting and purifying drinking water from a creek. All of a sudden, behind a bush, I see something I cannot quite identify; coming closer, I see that it is a hair-covered mass, which proceeds to leap out from the underbrush and stare at me. I am stunned; it is quite tall, appearing to ambulate in the manner of a human. It stares me in the face for what seems like an eternity, before finally strolling off into the dense green cacophony of thickets, never to be seen again. After it leaves, I look down at the ground, seeing footprints. Spilling plaster into them, I take the casts home to show everyone. It has been a frightening, yet massively rewarding, day for me; I got the fright of my life upon seeing this creature, but now I have the privilege of being able to say that I have set my eyes on the notorious Bigfoot.

This scenario is by no means singular or unique. Since at least about sixty years ago, if not earlier, witnesses have reported coming face-to-face with creatures resembling upright-walking, bipedal hairy primates in various locales, ranging from the snow-covered peaks and valleys of the Himalayas, that mountain range formed by the collision of the former continent of India with Asia earlier in the Cenozoic Era, to all parts of North and South America, to even places such as Australia, where a similar creature known as the Yowie has been reported to roam the Outback.

Besides sightings and videos, including some famous examples, such as the Patterson-Gimlin Film, the evidence most often marshaled by supporters of these creatures' supposed existence consists mainly of footprints, excrement, and hairs. Recently, numerous hairs alleged to belong to anomalous primates from around the world were tested by hominid geneticist Bryan Sykes and colleagues. They arrived at the conclusion that the hairs came from a wide variety of known animals, ranging from ungulates to bears, with some hairs from the Himalayas, reportedly from a Yeti, being found by said study to belong to an as-of-yet unknown variety of Polar Bear. A subsequent study by Eliecer E. Gutierrez and Ronald H. Pine arrived at the conclusion that the hairs likely came from the known Himalayan Brown Bear, with there being no reason to suppose that they came from anything else.

Another study found that the reported range of Sasquatch encounters in North America where sightings were most frequently reported matched up nearly perfectly with the known range of the American Black Bear, Ursus americanus. The authors, reflecting on their findings, noted that the idea that two sympatric species of large mammals with reportedly similar superficial appearances and habits would inhabit the exact same region left them incredulous.

Reality television programs such as Finding Bigfoot on Animal Planet have now added fuel to the fire with their claims of investigating these reported creatures scientifically, while, with all due respect to the people involved in the series, their investigations are a prime example of what I consider to be the pseudoscience which mars cryptozoology and gives it a bad reputation among the scientific community. The investigators on that program repeatedly perform strategically-placed calls to attempt to attract Sasquatches with them, subsequently interpreting any response they get, however vague, as said Sasquatches responding to their communication. First of all, they need to provide evidence that these calls they are using are really Sasquatch calls, and how we can know they are such, if Sasquatch has not even been confirmed to exist, let alone discovered or studied in any intensive detail. Second, it seems to me like they too readily employ confirmation bias when it comes to interpreting their findings. Since they have the mindset that they are communicating with Bigfoot, they interpret any calls they hear as coming from Bigfoot, automatically, despite the lack of any solid evidence, whatsoever, that this is, in fact, the case.

Another recent event in the community of Bigfoot advocates was the claims by Melba Ketchum and colleagues that they had found Bigfoot DNA. However, Ketchum et al.'s study was published in their own scientific journal that had been purchased by Ketchum herself months earlier, without passing through the rigorous process of peer review necessary to cement its findings as scientifically sound. The process of publication of the article was also marred by scandalous events, including one researcher's insistent claims that he had photographed the face of a Sasquatch, really nothing more than a Chewbacca mask. Ketchum concluded that Sasquatches resulted from a hybridization event between humans and another unknown hominid species in the Pleistocene, about fifteen thousand years ago.

After all of these different avenues of investigation and recent events that have occurred surrounding Yeti and Sasquatch research, I must say that, as someone who once passionately thought that the evidence supported the existence of a species, or several species, of closely-related unknown bipedal primates inhabiting the Palaearctic and Nearctic ecozones, and possibly the Australasian one, as well, I have now drifted to a more skeptical point-of-view on these cryptids, given that the evidence that seemed most compelling to me in the past has now been tested, and, with the exception of Ketchum et al.'s controversially-derived results, genetic evidence of unknown primate presence was not detected.

What really caused me to reexamine my views and take on a more skeptical position, though, were two main reasons. One reason was the study comparing the distribution of Sasquatch sightings to the distribution of American Black Bears, which really impressed on me what a coincidence this would be if a Sasquatch was a real unknown primate species, as well as the study of alleged Yeti hairs carried out by Bryan Sykes et al., and the subsequent follow-up study conducted by Eliecer Gutierrez and Ronald Pine. As much as I wanted it not to be true, because of how much it dampened my hopes of discovering a real new species of bipedal, hairy hominid roaming the forests of North America and Asia someday, I had to admit that Occam's Razor supported misidentifications of ursids as being one of the most common reasons for reported Sasquatch and Yeti sightings. I myself have seen videos of bears walking bipedally, and it is striking how similar their method of ambulation can appear to that utilized by hominids. A witness could very easily be forgiven for mistaking a bear walking upright on its hind legs for a Bigfoot or a Yeti, especially if they were walking through an area of wilderness where Bigfoot or Yeti sightings have been reported in the past, and they were expecting to see one, creating a psychological condition in which they were more likely to interpret any large bipedal furry creature glimpsed by them as said cryptid.

The other reason was the fact that, as pointed out previously by American physical anthropologist and Sasquatch proponent Grover Krantz, since people have reported sightings of similar creatures to the Yeti and the Sasquatch all over the world, with sighting reports implying that they have nearly a cosmopolitan distribution, this undermines the credibility of the case that they furnish evidence of an actual species of undiscovered primate. The more widespread the sightings are around the world, and the more random their distribution appears to be, the less likely the putative existence of the creatures seems. Indeed, such worldwide distribution would seem to hint at common universal factors in the human psyche perhaps playing a role in the phenomenon of reported sightings of these creatures.

Overall, I am still open-minded, and I think it is still possible that Sasquatch, Yeti, and their ilk might, indeed, exist and are roaming the wilderness at this very moment. I just do not see enough evidence to cause me to commit to such a hypothesis at the moment. Meanwhile, there are still some other mystery primates whose potential existence is, I think, grounded in plausibility, such as the Orang-Pendek of Sumatra, which has the advantage of having reports of it be confined to a specific geographical locale, being described as sounding like a real, ordinary animal, rather than a mythologized beast, as the others sometimes sound like, the presence of fossil evidence at said locale which might be of pertinence (the "Hobbit", or Homo floresiensis), and the fact that it seems to inhabit a feasible-sounding habitat for a creature of its description.

The topic of mysterious primates in cryptozoology has attracted much controversy and consternation over the years, and I doubt this trend is going anywhere anytime soon. I remain open-minded about the whole situation, and trust me, I would be ecstatic with joy if I turned on my television set or looked in my newspaper tomorrow morning and saw that a Yeti or a Sasquatch had been captured, proving the existence of a new hominid species roaming the temperate ecozones of the Earth's Biosphere. Secretly, I hope my newfound skepticism is totally wrong, and, indeed, I would love nothing more than for it to be proven wrong. After all, at heart, I am a romantic in all things, not least the zoological, and few things, if anything, can captivate me more than the thought of new species of exotic animals, hidden for ages, being discovered in our own backyards.

Saturday, January 14, 2017

Epigenetics: An Overview

In my articles on zygotes and embryos, I mentioned non-genetic factors that play crucial and significant roles in the development of individual organisms; one of those processes I mentioned was epigenetics, which I alluded to in one sentence. In reality, such a brisk glossing over does this very important and complex subject no justice, so I have decided to pen this present article to cover this topic, in particular.

What is epigenetics? To understand, we need first to cover what genes and genomes are. Genes are portions of DNA (Deoxyribonucleic Acid), the nucleic acid macromolecule inherited from an organism's ancestors. Each individual gene is like an instruction to produce a particular characteristic, and the entire set of genes in the DNA, all taken together, is known as a genome. The process of how these instructions actually create the structures that they code for is known as gene expression. This is where epigenetics comes in. Epigenetics is the process of controlling and modfying how genes are expressed during the process of gene expression.

This seemingly innocuous fact has wider implications, for it shows that, thanks to epigenetics, it is truly inaccurate to say that we, as individual organisms, are the products of our genes alone, and that our genes represent our destinies. In reality, we are the products of genes, as well as processes such as epigenetics, which result in non-genetic factors, including other components of the cell, such as cytoplasm, and external factors in the environments inhabited by us, playing a critical role in shaping who we are as individuals.

Another important aspect of epigenetics to note is that it is, to some extent, heritable. At the time of fusion of the gametes, ovum and sperm, the resulting offspring inherits an epigenome (a set of epigenetic factors somewhat analagous to the genome, which is composed of genes, hence the name) from both of its parents.
Yet another important aspect of epigenetics is that, in addition to being heritable, unlike genes (which generally remain fixed throughout an individual organism's life cycle), epigenetics can be altered by an individual's experiences in their life, and this altered epigenome can then subsequently be passed down to offspring at the time of reproduction. In other words, changes to the epigenome incurred during an organism's life are heritable, allowing them to be existent in the offspring of said organism from the time of said offspring's conception.

An organism's epigenome is modified by its environment and experiences throughout its life, from the time it is conceived by the fusion of each of its parents' gametes to the time of its death.

This process of changes to an individual's phenotype brought on by an individual's life experiences that are subsequently inherited by its offspring is quite reminiscent of Lamarckism, a hypothesis regarding how evolution worked proposed by Jean-Baptiste Lamarck, positing that, for example, a giraffe stretching its neck, lengthening it slightly, to reach the tallest leaves on a tree would bear children with slightly longer necks than it, and so on, until, over time, the giraffe population, as a whole, became long-necked. This hypothesis was adopted by many early proponents of evolutionary theory, including noted American paleontologist Edward Drinker Cope, but was generally discredited once Charles Darwin's theory of evolution by natural selection arrived on the scene.

However, epigenetics has, in a sense, resurrected Neo-Lamarckism. In addition to noting this, it should also be noted that, according to recent discoveries, even phenomena normally thought to be entirely the providence of the nervous system, such as memories, might fall under the purview of epigenetics. I am planning to devote another full article to this later, but I think it shall suffice to say here that the existence of a phenomenon known as cellular memory, the ability of cells, including some besides those of the nervous system, to record information incurred during an organism's lifetime in the form of memories, has begun to be supported by studies. This means that experiences that were endured by an individual's ancestors and which left their imprints in said ancestor's cells were passed on to their descendants in the form of their gametes, meaning that even things such as memories could be, to some extent, heritable, in a sense, due to epigenetics.

Overall, epigenetics is among the most fascinating frontiers in the field of developmental biology and genetics, and research on it is still in its early stages. In the future, more research could shed light on this wonderfully intriguing, and strikingly imperative, area of biology.

Monday, January 9, 2017

Responses To More Claims About Zygotes And Embryos

Here are some additional arguments I have encountered, in various sources, against zygotes and embryos being living individual organisms, which I will review and judge on their own merits here, as well.

One of the most popular arguments, widely believed by many, including some in the scientific community, is that, prior to fourteen days after fertilization of the oocyte by the spermatozoon, the embryo is not yet an individual because there is the potential for monozygotic twinning to occur, causing there to be two individuals instead of one. This argument assumes that this split into two individuals erases the existence of the original embryo, leaving two progeny in its wake. However, in reality, it is thought that monozygotic twinning occurs at the blastocyst stage of embryonic development, in which the cells of the inner cell mass have separated from the cells on the outside of the embryo, which form a structure called the trophoblast. When monozygotic twinning occurs, part of the blastocyst separates from the rest of the embryo, splitting off and giving rise to a genetically identical clone, or twin. It is very important to note here that this process does not erase the existence of the original embryo, and, in fact, due to the embryo's amazing ability to heal its wounds and regenerate missing cells, it actually makes a pretty decent recovery afterwards. Neurobiologist Maureen L. Condic compared this process to the analogy of an adult human's arm being cut off and used to create a clone of itself, while the original is able to regenerate its missing arm afterwards.

Indeed, the very mention of cloning allows me to segue into the mention of the fact that, as human cloning, by the merging of any reprogrammed somatic cell with an oocyte, is at least hypothethetically possible, the truth is that you or I have the potential to be cloned, which is basically the same process as monozygotic twinning, at any moment. Therefore, if we utilize the argument against individuality from twinning/cloning, then, no adult animals, including humans, are ever individuals, as they could, potentially, be cloned at any time. This is obviously an absurdity, which means the above argument must be, as well.

Another argument, this one based more on lack of information than anything else, really, is that, as embryos are capable of being frozen and thawed back out many years later, emerging alive, while this has not been done to adult animals yet, this proves that embryos are less alive than adult animals. Yet a simple exploration of what actually happens during the embryo freezing process dispels this one entirely. During this process, water is expelled from the cells, as, since water forms sharp crystals that penetrate and kill cells when it freezes, it is dangerous and deadly to allow an organism to freeze without first doing so. Then, antifreeze is put into the cells in place of the expelled water. The only reason why this has, to date, been done successfully only on embryos, and not on adults, is simply because it is far less practically feasible to carry out this process on an adult organism, simply because the latter is so much larger than an embryo. It is only a matter of practicality based around physical size. There is nothing inherently different between an embryo and an adult that causes this difference. Who knows? Perhaps, in the future, preserved, frozen adult humans will be a reality, just like preserved, frozen embryonic humans are now.

Lastly, there is the argument that, since the trophoblast forms what are commonly referred to as extraembryonic tissues, including the placenta and yolk sac, while the inner cell mass forms what is thought of as the embryo proper, before the separation of the trophoblast from the inner cell mass at the blastocyst stage, the embryo cannot yet be an individual. However, a closer examination of this argument reveals critical faults. The fact that the structures formed by the trophoblast are referred to as extraembryonic structures is rather misleading; in reality, they are, indeed, part of the embryo's body, just like what is thought of as the embryo proper. The fact that they are utilized only during the antenatal stage of life, and subsequently shed upon parturition, does not make them any less part of the embryo's body than the fact that milk teeth are utilized only during childhood, and are subsequently shed, makes them any less part of postnatal children's bodies.

Overall, these three additional arguments against zygotes and early embryos being individual organisms can all be soundly rejected. The argument from twinning can be rejected due to the fact that twinning only produces a new embryo, while the original remains, and that any adult organism could potentially be cloned at any time, the argument from freezing and preservation can be rejected due to the fact that the difference between adults and embryos in this respect is only a matter of size, and nothing more fundamental than that, and the argument from extraembryonic structures can be rejected due to the fact that these are, indeed, parts of the embryo's body, which are subsequently shed after birth.

References:

Condic, Maureen L. (2014). Totipotency: What It Is And What It Is Not. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3991987/)