More Random Thoughts

* What if the Younger Dryas extra-terrestrial impact didn't happen? 

Pleistocene megafauna might have survived. The Clovis culture would have lasted longer. Native American cultures in North America might have been more patriarchal. Göbekli Tepe might not have been built at all, or might have been very different. The Neolithic Revolution might have arrived 4,000 years earlier. The genetics of European hunter-gatherers might have been more diverse.

* There is more than one scenario by which brain evolution could be next level. 

One is exemplified by the Cylons of Battlestar Galactica who have essentially the three main layers of the human brain plus a new one on top of that - dolphins come close to that. Another is exemplified by octopi who have a completely different brain structure with is decentralized with many sub-brains throughout their bodies. Yet another would be the cyborg approach (perhaps exemplified by Ghost in the Machine) where brains would be part human and part computer (perhaps the most likely as it has already been done at a very limited level).

* “Eternity is two people and a ham." - Irma Rombauer in The Joy of Cooking. But the price is right. You can get so much red meat for so little money when there are holiday ham sales.

* I visited the Colorado History Museum today and saw, among other things, the 90s exhibit. It is actually fairly stunning how little fashion, music, and movies have changed in the last 35 years, even though technology has changed dramatically. There was a much smaller generation gap between me and my children, culturally, than there was between me and my parents (or my wife and her parents).

* I still don't really understand why the dust bowl of the 1930s happened, or what the risk of it recurring is.

* My son is in Mexico City with his (serious, long term) girlfriend. He is almost exactly the same age that I was when I went there on my honeymoon.

* The U.S. Navy has been quietly developing unmanned surface and undersea ships that are just about ready for "prime time" as important components of our overall naval fleet. Here are some recent examples:

For example, the Australian Eureka unmanned or minimally manned ship has a 1,150 mile range, a 44 ton payload, can travel at 50 knots (60 mph a.k.a. 100 km/hr), and can launch Tomahawk cruise missiles and anti-ship Naval Strike Missiles (NSM). But is fairly small at 36 meters in length.

The Lionfish UUV (i.e. drone submarine) is about to enter service.

Lionfish is designed to address critical undersea warfare needs, including mine countermeasures, intelligence, surveillance, and reconnaissance (ISR), anti-submarine warfare, and electronic warfare.

The REMUS UUV family delivers critical advantages across modern naval operations and the autonomous systems have been proven to operate independently or in conjunction with crewed platforms — such as Virginia-class nuclear submarines — to extend mission range, reduce detection risk, and limit personnel exposure.

The U.S. Navy has a 100 foot long, 100 ton, unmanned surface vessel (USV) in the works (confusingly the same article seems to describe it as a 180 foot, 240 ton USV). It would have a range of thousands of miles.

The vessel is envisaged to be multi-role, capable of transporting logistics payloads, conducting ISR (intelligence, surveillance, reconnaissance) missions, or supporting naval munitions delivery without human oversight.

* My wife is currently watching White Lotus. One of the striking parts of the show is how aptly it captures the ways that men and women completely misunderstand each other because they have very different communications styles. To oversimplify, men are much more direct. Men rely far less on implied meanings and expecting people to "take a hint" than women. Women, in turn, overthink what men say, trying to look for hidden meanings in what men say that aren't there. Women, meanwhile, underestimate how much men can be hurt when they take what women say literally, when what women really mean is different, and is supposed to be implied from context. It also puts the lie to the notion that women are better communicators. Both are men and women are bad at communicating with members of the opposite sex. This mirrors differences in national communications styles. Germans, for example, are much more direct than Americans, while the Japanese, for example, have a much more indirect communication systle.

Potential Approaches To Genetic Engineering

We are fast approaching the point where the transhumanist goal of intentionally modifying humans to further our own objectives with tools that include genetic engineering is possible.

There are several approaches that could be taken to doing this that are easier and less sophisticated than simply synthesizing whole genomes, or large parts of them from scratch. And, these are the approaches the would probably dominate the early days of transhumanist genetic engineering that seeks to improve the human genome. 

Of course, each approach also comes with its own particular risks. The risks mostly flow from the fact that biological systems are highly interrelated and tweaking any one part of them can have unintended consequences if we don't perfectly understand those interrelationships (which will probably won't for the foreseeable future).

Fixing Existing Simple Genetic Disorders

The first wave of genetic engineering, which is just starting to be utilized medically, is to change single genes that cause Medellin genetic disorders like sickle cell anemia or achromatopsia, to cure these disorders.

This is among the lowest risk forms of genetic engineering. A known harm is alleviated. But it isn't completely without side effects. The sickle cell anemia gene also creates resistance to malaria when only one rather than two copies of it are present. But removing this benefit from someone's descendants is a small price to pay in someone who had sickle cell anemia and doesn't live in a place where malaria is a problem (or when someone who can be protected from malaria by other means such as a malaria vaccine).

Purging Recessive Genetic Disorder Genes

Everyone has some recessive genes for genetic disorders. And, as long as you don't have children with someone else who has the same recessive genes, this is basically harmless.

The main reason that inbreeding is fitness reducing is that it increases that likelihood that a couple's children will end up with both copies of recessive genes for genetic disorders.

But, in addition to genetic engineering to remove genes that cause genetic disorders from people who already have genetic disorders, essentially the same approach could be used to remove recessive genes that cause genetic disorders from people who are merely carriers for those genetic disorders.

This might be particularly attractive for participants in a space colonization mission that would have a low effective population size and, necessarily, a higher inbreeding coefficient.

This kind of genetic engineering is particularly low risk, because we would be replacing the recessive gene known to present a risk of a genetic disorder, with genes found in the vast majority of the population that are known to be harmless.

Genetic Engineering With Existing Human Coding Genes

It is elementary that there is genetic diversity among humans. Some people have genes that make you tall or smart. Other people have genes that make you short or stupid. People have different blood types, different skin and eye and hair colors, different skin and hair textures, different ability to tolerate high altitudes, etc.

One fairly straightforward, if not necessarily technically easy, form of genetic engineering is to take genes from people who have a desirable genetic trait and place them in people who do not have that trait (often replacing a gene that codes an alternative to that trait).

In other words, basically doing that same thing that could be accomplished with selective breeding, but much more rapidly, directly, and precisely.

This is higher risk than simply removing recessive genes that cause genetic mutations (and even the example of sickle cell anemia which also confers malaria resistance illustrates the trade offs of that), because it could be that a known desirable gene interacts with other genes in an important unknown way that is disrupted when the known desirable gene is transplanted. But it is still lower risk than giving someone a gene that isn't found in humans at all.

Tweaking Top Level Designs That Utilize Existing Coding Genes

Our DNA devotes lots of its coding genes to the blueprints for a mix of proteins, and how to combine those proteins into particular kinds of tissues, and how to combine those tissues into particular organs and structures in the human body. By comparison, our DNA devotes a far smaller share of our genome to specifying which organs and structures go where, and how many of those structures we have.

A genetic modification that hacks this small portion of our DNA governing which organs and structures go where and how many of them we have could create noticeable macroscopically observable changes with comparatively minor tweaks to our DNA and with less risk of adverse side effects on the complex, multifaceted biochemical interrelationships of other parts of our bodies.

For example, a tweak to our DNA that gave us four figures or six, instead of five, would be much easier to accomplish than a tweak to our DNA that gave humans the organ that electric eels use to create electromagnetic shocks which we don't have the blueprints for in our genome.

Similarly, tweaks to our DNA to give us an extra pair of eyes in the sides of our heads, or an extra pair of kidneys, or to rearrange the location of the internal organs in our torsos, ought to be possible with a fairly modest amount of DNA modification.

Genetic Engineering With Pseudo-Genes

Pseudo-genes are genes in our DNA that are no longer part of our coding DNA and have been deactivated by mutations.

At this point, their main practical use is that they allow us to trace historically what genes organisms have lost due to mutations, approximately when that happened, and what those genes looked like immediately prior to being deactivated.

For example, one deactivated gene allowed predecessors to primates to produce their own Vitamin C, which was no longer critical since fruit supplied it. Another allowed us to better break down uric acid in our blood, which has bad aspects since this can cause gout, but also helps us turn fructose into fat which helps us weather fruit scarcity in the winter. We've also lost taste receptors for bitter tastes, in part, because we've learned to distinguish safe and unsafe plants culturally so we don't need the receptors as much.

The thing about pseudo-genes, though, is that often a single slight mutation can undo the mutation that deactivated them in the first place, can reactivate the ability of the pseudo-gene to make the very complex molecule that was genetic fitness enhancing at some point in our evolutionary history.

Mutations that reactive pseudo-genes are extremely rare as a matter of random chance. But if one is engaged in intentional genetic engineering in order to do a transhuman biohack because you believe that the pseudo-gene might be fitness enhancing at our current level of technology and in current environmental conditions, it would often be easier to reactivate a pseudo-gene than it would be to insert all of the genetic code necessary to code a molecule into someone's DNA with a much more complex custom designed retrovirus.

A catalog of pseudo-genes in humans is basically a menu of biological functions that could easily be added to people with a simple biohack.

The risk here is that pseudo-genes were usually purged from the genome to the point of fixation for a fitness enhancing reason. Sometimes the circumstance that enhanced fitness at the time is no longer present, but sometimes it is and we just don't understand it well enough.

Another possibility to consider is that if much of the 90% of the human genome that is non-coding really is literally "junk DNA" that doesn't serve any fitness enhancing function, there might be some form of benefit to simply purging it from our genomes.

The risk of purging junk DNA, of course, is that some of it might have purposes that we just don't understand yet that are still important. So far as we know, simply having junk that does nothing in our DNA isn't a big problem.

Genetic Engineering With Exogenes

Another categories of genes that code molecules which are out there are genes that aren't present in either the coding or non-coding DNA of humans, but are present as coding DNA in other organisms. I don't actually know what the proper scientific name for them is, but I'll call them for convenience in this post, "exogenes."

Suppose, for example, that a honey bee produces a pheromone not found in human genes or pseudo-genes that it would be nice for humans to have. You could cut that gene out of the honey bee genome, splice it onto a retrovirus, infect a human with that retrovirus, and then that human and that human's descendants could produce that pheromone too.

Of course, inserting exogenes into a human could potentially be harmful in all sorts of hard to see ways, because we have no good way of knowing if the exogenes are incompatible with our existing genome until we try it.

Genetic Engineering With Derived Genes

There are some genes in humans that share a common ancestor with different genes in another species, even though the human genes now code for a different molecule with a different purpose than the non-human gene with which it shares a common ancestor.

For example, some of the biochemicals in human saliva are derived from the same ancestral biochemicals that evolved in some snakes into a kink of snake venom.

If you wanted to make it possible for humans to produce that venom, it might be easier to genetically modify human DNA that makes those biochemicals in saliva into DNA that produces snake venom, than it would be to insert the entire snake venom exogene into a human through a much larger retrovirus than one that would merely tweak our existing salvia biochemical gene.

This is less risky that a straight out exogene, because humans already have something similar, but it is still far from risk free.

For example, maybe snakes have genes that give them immunity from their own venom, in addition to the genes that create the venom, that a human with a tweaked salvia gene that creates the same venom would not have.

Small Tweaks To Create Chemically Similar Molecules

Similar to genetic engineering of genes with a common origin is genetic engineering of genes that produce a molecule that is chemically similar to another molecule, even if the genes that produce the two different biochemicals do not share a recent common origin.

For example, the caffein molecule and the chocolate molecule differ by only a single atom. So, it probably wouldn't be too hard to engineer a cocoa bean that was caffeinated instead of chocolaty, or a coffee bean that was chocolaty instead of caffeinated.

The general concern about unintended consequences that is present throughout genetic engineering is present here, but to the extent that tweak is small, and we understand what the purpose of the molecule being tweaked is in the original organism, the risk can be fairly modest.

A One Time Anti-Aging Drug Works Wonders In Mice

A single shot of a treatment already approved in humans as a cancer treatment can dramatically extend the lives of mice, dramatically reducing age associated ailments, without significant side effects.

Scientists have found a way to reprogram T cells to fight aging. After using them to eliminate specific cells in mice, the scientists discovered they lived healthier lives and didn't develop aging-associated conditions like obesity and diabetes. Just one dose provided young mice with lifelong benefits and rejuvenated older mice. . . .

They discovered CAR T cells could be manipulated to eliminate senescent cells in mice. As a result, the mice ended up living healthier lives. They had lower body weight, improved metabolism and glucose tolerance, and increased physical activity.

All benefits came without any tissue damage or toxicity.

"If we give it to aged mice, they rejuvenate. If we give it to young mice, they age slower. No other therapy right now can do this, " says Amor Vegas.

Perhaps the greatest power of CAR T cells is their longevity.

The team found that just one dose at a young age can have lifelong effects. That single treatment can protect against conditions that commonly occur later in life, like obesity and diabetes.

. . .

CAR T cells have been used to treat a variety of blood cancers, receiving FDA approval for this purpose in 2017.

From Science Daily, citing:

Corina Amor, et al., "Prophylactic and long-lasting efficacy of senolytic CAR T cells against age-related metabolic dysfunction." Nature Aging (2024) DOI: 10.1038/s43587-023-00560-5.

Crazy Smart Computers

Computers can do things somewhat akin to fantasy level martial arts, in that they are in principle possible, but no living person has the ability to do them, because the precision and computation required to do so is so great.

Arthur C. Clarke said that “Any sufficiently advanced technology is indistinguishable from magic.” Here’s an example. You know those ubiquitous little LEDs on devices like speakers, card readers, microphones etc. that simply indicate that the device has power? The authors show that these LEDs can bleed information about power consumption that can be used to deduce when and for how long a computer is computing cryptographic keys and that can be used to deduce the keys. For example, using a “hijacked” security camera the author’s were able to film the power LED on a smart card reader from 16 meters away and from that able to deduce the keys. Paper here. . . .

Now some people will say, well all you have to do is make sure the LEDs are properly insulated from the main power and adjust the cryptographic algorithms to not take some shortcuts and your systems will be safe. Uh huh.

Eliezer Yudkowsky has a more realistic perspective. Although this is not about AI per se, he notes this is a good example of the kind of thing that a superintelligence could do that would not have been predicted in advance and would seem to require magical powers.

From Marginal Revolution. 

Another Path For Transhumanism: Design Improvements

When one thinks about the prospects of genetic engineering and other ways of improving the human body and mind, which is basically what "transhumanism" is about, cosmetic improvements and functional improvements come to mind. (The engineering challenges of actually writing and not merely reading a genome are not insubstantial but they are not entirely insurmountable either.)

But many people fail to appreciate the many design flaws in the human body from wisdom teeth, to tail bones, to the appendix, to the design flaws in the human eye, to immune system gaps that have to be addressed with vaccines. Improving these flaws is one obvious and not very ethically troubling task for genetic engineering.

The human eye is marvelous but also very poorly designed. The poor design is evidence against intelligent design and in favor of the “unguided, unplanned, messy, quirky, and historically contingent” process of evolutionary design. A short piece from 2008, Suboptimal Optics: Vision Problems as Scars of Evolutionary History, does a nice job explaining.

Most well known is that the wiring is backwards.

The most obvious design flaw of the retina is that the cellular layers are backwards. Light has to travel through multiple layers in order to get to the rods and cones that act as the photoreceptors. There is no functional reason for this arrangement—it is purely quirky and contingent.

Even in a healthy and normally functioning eye, this arrangement causes problems. Because the nerve fibers coming from the rods and cones need to come together as the optic nerve, which then has to travel back to the brain, there needs to be a hole in the retina through which the optic nerve can travel. This hole creates a blind spot in each eye. Our brains compensate for this blind spot so that we normally do not perceive it—but it is there.

From a practical point of view, this is a minor compromise to visual function, but it is completely unnecessary. If the rods and cones were simply turned around so that their cell bodies and axons were behind them (oriented to the direction of light), then there would be no need for a blind spot at all.

Cephalopod’s like octopuses took a slightly different evolutionary path and have a better design:

But the reversal of the wiring isn’t the only design flaw.

The arrangement of the extraocular muscles—the muscles that move the eyes—is also difficult to explain without appealing to evolutionary contingency. There are more muscles than are minimally necessary and yet there is no functional redundancy. In order to move a sphere in any direction, only three muscles would be necessary, evenly spaced like the legs of a tripod. The human eye has six—the superior, inferior, lateral, and medial rectus, and the superior and inferior oblique. And yet, despite the extra three muscles, the loss of function of any one muscle causes an impairment of eye movement and results in double vision or displaced vision. A more frugal design with only three muscles would be more efficient and less prone to malfunction, as there are fewer components to break down.

If the eye were to be designed with more than the minimal three muscles, then it would make sense to arrange the muscles so that the loss of one or even more would not impair eye movement.

From here via Marginal Revolution which also has some interesting comments.

Immortal Rats

Naked mole rats are rather ugly, but they age well. More specifically, they are the only mammal that doesn't appear to die of old age: "these rodents live to around 35 years, as opposed to a "regular" rat's six years, and the naked mole rat doesn't seem to actually age before it dies." Specifically:

the chance of dying for the mole rats did not increase as they aged. All other mammals that have been studied have been found to conform to what is known as Gompertz's mortality law, which states that the risk of death for a typical mammal grows exponentially after they reach sexual maturity—for humans, that means the odds of dying double every eight years after reaching age 30.

Sure, they die. But, they don't undergo the physical decay with age that characterizes other mammals whose bodies start to fall apart at a certain point. Female naked mole rats remain fertile pretty much until they die.

Needless to say, naked mole rats will now be at the center of efforts to figure out the aging process so that humans can cheat it as much as possible.

Naked mole rates are also almost cold blooded, which may not be unrelated. Crocodiles and some sharks, both of which are also cold blooded, seem to continue to grow indefinitely, with a case in point being the Greenland shark which is believed to live to be as much as 512 years old, older than any other known vertebrate.

Chemical Target For Extending Child-Like Language Acquisition Identified

Tests in lab mice have identified a single chemical that can be manipulated to extend the period during which people would acquire new languages with the ease of children, portending a nootropic drug revolution. 

By disrupting adenosine signaling in the auditory thalamus, we have extended the window for auditory learning for the longest period yet reported, well into adulthood and far beyond the usual critical period in mice," said corresponding author Stanislav Zakharenko, M.D., Ph.D., a member of the St. Jude Department of Developmental Neurobiology. "These results offer a promising strategy to extend the same window in humans to acquire language or musical ability by restoring plasticity in critical regions of the brain, possibly by developing drugs that selectively block adenosine activity."

The paper is:

Jay A. Blundon, et al., "Restoring auditory cortex plasticity in adult mice by restricting thalamic adenosine signaling." Science, 2017 DOI: 10.1126/science.aaf4612

Undead Marriage

You marry until "death do you part".

If one of you becomes undead - a vampire or a zombie or a mummy or a ghost, for example, is that a form of death that breaks the marriage bond? Is there a distinction between the impact those possibilities, respectively, could have on marriage? Perhaps "brain dead" and not "heart dead" is what matters. Perhaps you still need to be corporal?

Of course, if you are Mormon, you "marry for eternity" and presumably the transformation to undead status doesn't matter.

Could it be that Mormons were familiar with the undead and saw how immoral it was to end a marriage just because one of the parties was dead?

Probably not, but it is an interesting theory.

Cyborgs Are Now

A customizable soft robot that fits around a heart and helps it beat has now been developed by researchers, potentially opening new treatment options for people suffering from heart failure.

From here.

Always Human - A Quirky Comic For A Quirky Day

The heartwarming girl meets girl science fiction romance webcomic, Always Human, that also has something to say about transhumanism is just the thing for a quirky day like leap day.

Short Takes About Organs In Organisms

* As long suspected, there are distinct patterns of methylation in the epigenome for tissues for each of the major kinds of organs in a person.  And, we have reached a point where scientists can now read those methylation patterns.

* It turns out that taste buds are a subclass of a larger category of organs in the body that analyze the chemical content of molecules presented to them, which appear throughout the body.  The results of the taste and smell organs reach our conscious brain, but, for example, something very like taste buds in our kidneys are used to determine if it is correctly filtering our blood so that only stuff that should be removed from the body ends up in urine.

* Scientists suspected that they had discovered a previously undetected human organ in the 1990s. This discovery was put to use in clinical applications that in 2013 were published and shows a new treatment for high blood pressure.

Removing one of the tiniest organs in the body has shown to provide effective treatment for high blood pressure. . . . The carotid body -- a small nodule (no larger than a rice grain) found on the side of each carotid artery -- appears to be a major culprit in the development and regulation of high blood pressure. . . . Normally, the carotid body acts to regulate the amount of oxygen and carbon-dioxide in the blood. They are stimulated when oxygen levels fall in your blood as occurs when you hold your breath. This causes a dramatic increase in breathing and blood pressure until blood oxygen levels are restored. This response comes about through a nervous connection between the carotid body and the brain. . . . "Despite its small size the carotid body has the highest blood flow of any organ in the body. Its influence on blood pressure likely reflects the priority of protecting the brain with enough blood flow."

The journal article reference is: McBryde, et al., "The carotid body as a putative therapeutic target for the treatment of neurogenic hypertension.", Nature Communications (2013); 4 DOI: 10.1038/ncomms3395

* In mammals, the vomeronasal organ is the one popularly associated with receiving chemical communications from other individuals, particularly chemicals known as pheromones.  While there is some dispute regarding the issue, it appears that the weight of the evidence indicates that adult humans generally have at least one vomeronasal organ, in the form a a "pit" partway down at least one side of your nose (there is no disagreement that the organ is found in the same location in embryos).

Numerous reports of a structure identified as the VNO in the nasal septum in adult humans agree that it is a blind ending diverticulum in the septal mucosa opening via a depression (the VNO pit) into the nasal cavity ∼2 cm in from the nostril.

The connection between the VNO pit and chemical communication among humans isn't firmly established empirically, but there is very good circumstantial evidence to suggest that this is the mechanism.

There is fairly clear evidence for chemical communication among humans. The most notable example is a trend towards synchronization of menstrual cycles in women who live together (McClintock, 1971). Stern and McClintock have recently deduced the presence of two substances that can mediate this response when extracts of skin secretions are placed on the upper lip (Stern and McClintock, 1998). Thus, the signals are most likely to be airborne chemicals. The trend towards synchronization arises from either shortening or lengthening of the cycle by secretions produced at different phases of the donor’s cycle [but see the comment by Whitten (Whitten, 1999)]. The substances involved are unknown and although the effect does appear to be chemosensory, there is no evidence that it is due to vomeronasal sensory input.

Another data point which has been attributed to chemical communication through pheromones, but could instead be due to subconscious awareness of subtle visual cues, comes from studies which have found that men at strip clubs consistent prefer performers and tip them better, when performers are not on hormonal contraceptives and at the most fertile stage of their menstrual cycle, over other performers.

There is likewise suggestive evidence that VNO input should be largely a subconscious one.

Whether any of these findings are evidence for human pheromones is a different question. None of them meet the test for pheromone communication proposed below, i.e. evidence that the communication is beneficial (in the evolutionary sense) to both sender and receiver. The subjects in these studies had no conscious perception of odor stimulation, which could be a feature of vomeronasal input although not a sine qua non for pheromonal communication. The suggestion that vomeronasal input might be unconscious (Lloyd-Thomas and Keverne, 1982) comes in part from observations of vomeronasal system connections in the rodent brain. There are close connections with the amygdala and limbic system (Halpern, 1987; Meredith, 1991), the seat of emotional, hormonal and autonomic control, but there are only indirect connections with the cerebral cortex, generally considered to be the site of consciousness. The main olfactory system in general has good connections with cerebral cortex, but also has connections to the amygdala.

It is also worth noting that pheromones (a term that has more strict and less strict definitions, but at a minimum facilitate chemical communication between animals of the same type) need not always involve the VNO, even though they often do.

Whatever the definition of pheromone, there is no evidence that pheromones are necessarily detected by the VNO. Several recent examples in animals with well-developed VNOs make this clear. The response of newborn rabbits to the mother’s nipple (Hudson and Distel, 1986), referred to above, and the standing response of a receptive female pig to the male’s pheromone (Dorries et al., 1997) both depend on the main olfactory system. The recognition of newborn lambs by ewes also appears to depend on the main olfactory system (Levy et al., 1995), although a vomeronasal contribution has also been reported (Booth and Katz, 2000). Thus, even if an authentic pheromone response were to be documented in humans, that would not be evidence for a functional VNO.

The attraction of the VNO is the synthetic (or naturally harvested and purified) pheromones present an attractive and quite straightforward and non-invasive way to unconsciously influence people's behavior, and alternatively, at least a way of better understanding a possibly rich medium of unconscious communication (although the adult human VNO does clearly seem to be less developed than in many other kinds of mammals, like our olfactory system generally).

* There are some organs found in other kinds of animals that are not found in humans.  Some of the most interesting include spinnerets in spiders, and "the ampullae of lorenzini." These are found "in many fish and sharks, it allows them to sense electrical signals in the water emitted (usually) by other living organisms. This gives them a 'sixth sense' which allows them to find prey that is hiding underground or in the dark. It also is what prevents them from constantly running into the transparent glass of an aquarium."

Frogs have a third eyelid and can use their skin to breathe. We are also learning a lot about regeneration in amphibians, although the fact that this ability seems to be an ancestral state that was lost in less basal vertebrate species suggests that we proceed with caution as this ability apparently came with serious evolutionary costs.

* Some of the more interesting questions about the future of biotechnology come under the heading of "transhumanism", basically, redesigning the human body so that it can do something better or differently than ordinary humans.  This could involve adding a new organ not found in ordinary humans, or perhaps simply a new localized area or organ within the brain that confers some new mental capacity.

We increasingly understand how our complex human anatomy works in great detail at every level from gross anatomy to the chemical level, and can increasingly read the DNA and epigenetic codes that cause the human body to form itself in this way.  For example, while we've know the letters of the genetic code and some of its overall structure for decades, we are starting to now understand the "grammar" of the genetic code.  While in some respects, DNA is harder to understand than we might have naively hoped, many aspects of DNA seem to be uniform across all living things, so like most languages and sciences, once mastered, our knowledge may have broad applicability to unanticipated situations.

With new tools for DNA modification like CRISPR, and even less invasive tools the can modify epigenetic signals, it isn't unthinkable that we could start to write the codes that make our bodies in some way that would create a "transhuman" deliberately, although overconfidence of a type demonstrated in centuries of neuromedical missteps and fads, suggests strongly that hubris will produce unexpected consequences on more than one occasion, as well as raising serious professional ethical issues.  But, in the end, professional ethics never seems to be sufficient to prevent scientific breakthroughs in the long run.