How The Snake Got Its Venom

Question from Robert:
What would be your reasoning as to how the evolution of venomous snakes could have happened? Obviously, the first snakes did not start off with venom glands in their heads. That means that they were getting along just fine without any venom to kill their prey for hundreds of thousands or millions of years. So why in the world would venom glands evolve inside their heads? That is not ‘natural selection’. Indeed, that is completely unnatural. A creature wants to keep poison out of its body! So why would any creature start to make poison inside its body? That makes no sense at all. And it would potentially be extremely dangerous to that creature.

But just for the sake of argument, let’s say that such a totally bizarre thing occurred. So now what? You have snakes with venom glands in their heads. How in the heck are the snakes supposed to get the venom into their prey? That would be 100% impossible for snakes to do that without hollowed out, syringe-like, very sharp fangs.

That’s a HUGE problem. That means that snakes which somehow evolved venom glands, would then have to evolve syringe like teeth. And there is absolutely no way that could happen because that would require forethought and planning. And it would totally go against the theory of natural selection. Also, by the time that snakes could have strangely evolved syringe like teeth, their venom glands would have already been naturally phased out because those glands would have been totally useless for an extremely long time. But again, just for the sake of argument, let’s say that this second totally bizarre thing occurred. Now snakes would have had to evolve a structure that would connect the venom gland to the syringe like teeth. How could all of these bizarre things happen accidentally? …. or naturally?

Answer by SmartLX:
We don’t have to rely on my reasoning, not when Scientific American has a full article on this exact subject and Wikipedia has a good summary sitting right there. What the heck, here’s the National Geographic article too. These are literally the first three results when you Google “evolution of snake venom” so I guess you didn’t start there.

The first snakes actually did start off with venom glands because the glands first evolved in the ancestors of snakes, four-legged burrowing lizards more similar to the Komodo dragon. The proteins in venom share DNA with compounds that do other jobs. One is saliva, which breaks down organic material for digestion. Immune system proteins, which attack foreign elements in the body, are another. One compound that isn’t mentioned is stomach acid, but this is another dangerous substance that is essential to normal bodily function. We need poisons in our bodies to survive, only they’re poisons we’re able to tolerate because of how they’re produced and contained. Venom evolved many times over throughout the animal and plant kingdoms, because it has lots to build off.

As for delivery systems, of which there are many, you don’t need much of a starting point. Toads secrete poison on their skin and let it sit there, because the only animals they want to poison are those who try to eat them, so any number of bodily glands could have switched their purpose. Spitting cobras squirt venom forward, so what if they started by just plain spitting, or to be more specific, gleeking? With this technique, even humans can shoot liquid a long way from the body straight from a gland. A gland with a naturally effective nozzle like this can slowly evolve into either a weapon that can be aimed or a hard retractable tube that can inject, because every little bit closer it mutates to either one of these makes for more effective hunting and defense, and ultimately a better chance of survival.

With the specifics covered, let’s look at the overall nature of your challenge because it is VERY similar to those that have come before. You point to something remarkable and ask how it could have happened, and implicitly assert your own explanation by elimination after assuming no good answer is forthcoming. A textbook argument from ignorance (a harsh name, sorry, but the official one) and thus an informal fallacy, which is a failure of the premise of an argument to support its conclusion. It fails for several reasons: obviously it’s rebutted if an alternative answer is presented, but even if not it relies on the assumption that if you and I can’t think of a way then it’s impossible. We’d have to be gods ourselves for this to be true. I point out this fallacy whenever it comes in because it is the basis of many of the arguments for God, and every creationist argument. As a result, these arguments are only good for reassuring yourself and those who agree with you, because by themselves they have little power to persuade.

From Archaeology to Apes

Question from Kristi:
What is R. Dawkins’ view on Biblical archaeology? Scientists use fossils as artifacts, dinosaur bones, etc., yet when archaeologists find relief carvings of the Hebrews being taken into captivity by the Assyrians? Manfred Bietak has uncovered Semitic people’s remains dating back to time of the Famine around 1880 B.C, which would align with the information in the Jewish records and with the Biblical records of Genesis. Should not any artifact be considered scientific?

If we evolved from a complex organism such as the egg first then later to simpler organism such as the chicken, why are we not evolving anymore unless we are evolving into robots? Do you foresee the human race as fading out and becoming intelligent machines? We were once apes so would it be too much to believe we will re-evolve to something else?

Answer by SmartLX:
Richard Dawkins doesn’t seem to have made a public statement about Biblical archaeology as a whole, except to say there is no good evidence for any of the supernatural claims in the Bible, archaeological or otherwise. Evidence for non-supernatural elements of the Biblical narrative are another matter. There is plenty of evidence for the Assyrian captivity as you say. There were Israeli tribes about, no doubt, and they did leave their mark, but nothing in the archaeological record points to direct intervention by a deity with the interests of the Hebrews specifically at heart. Just because not everything in the Bible is untrue doesn’t mean the important bits for today’s believers are true.

Present-day human evolution is much like evolution at any other stage: so slow that any given generation doesn’t notice any major differences. We may be in the process of evolving into a very different form of organic life, but the process would take millions of years at least and research into the changes over the last few decades won’t give us much insight into that far future. Any transition to a machine or part-machine race is likely to be the result of deliberate self-alteration as a species, not Darwinian evolution.

Incidentally we are still apes. Leaving evolution and genetics aside completely, we meet the physical criteria to be classified as a “great ape”. Here’s a museum article.

Why We Aren’t All Smelling Our Butts Right Now

Question from Blink:
Hi guys. A theist asked me this question.

“Why are our eyes (not the anus) placed near our nose? Can you imagine how disturbing it would be if it were placed below our nose in place of our mouth!”

This is one of the many reasons why he believes in God.

I don’t know how to respond to this question, my instinct tells me maybe it has something to do with evolution. What is the appropriate respond to his question? Thanks.

Answer by SmartLX:
The anus is placed away from the mouth and nose because if any of our ancestors had developed the two close together, the species would have quickly been wiped out by anal-oral and anal-respiratory infections. On the other hand, the anus is placed near the genitalia and there’s a constant risk of infection between the two because that kind of infection isn’t usually enough to cause a major obstacle to survival, and there hasn’t been any major selection pressure to change it.

To make the same point more generally, if something being the case confers some kind of survival advantage, or if the alternative would make survival difficult, evolution is likely to encourage it to happen, because life will be easier at every stage for those who are closer to the ideal. Bad “ideas” are weeded out when the life forms that manifest them die.

But forget about evolution for a minute. Your theist asks why a particular thing is the case, and implies that if you don’t know, God must have done it. How utterly arrogant to think that just because the two of you may not be aware of any other explanations, reality must align perfectly with what HE thinks. This is a classic argument from ignorance, and the more people know what that is, the better for logic and reason in the world.

Counting Chromosomes

Question from Ken:
I’m agnostic. There’s one thing I’ve always wanted to understand about evolution for a while, and I hope this is the place to get it answered.

When I learnt about it, in school and university, they expressed the idea of increment changes (whether modifications of traits that were already there, or new traits through mutation) over time, passed on through generations, “chosen” by the ability to procreate and pass on genes. That, I think I get for the most part.

But what I never really understood is how the number of chromosomes could change over time. How can chromosome numbers increase and decrease? I mean… let’s say an individual somehow has it happen, shouldn’t he or she be unable to produce viable (or fertile?) offspring with others of the species because of the wrong numbers of chromosomes? How does chromosome number change at all? The only way I know is through issues that happen in meiosis, the kind of stuff that causes Down’s Syndrome, and the XXY and X gender chromosomal abnormalities that cause problems in humans.

So, my question is: How can chromosome number change in to produce a viable, fertile individual for it to be able to spread to an entire species?

Answer by SmartLX:
It’s a good question because a sudden whole extra chromosome full of junk, or a whole one gone missing, can indeed cause serious defects. That said, it helps to remember that a chromosome is merely a container of genes, and the number of chromosomes has very little to do with the amount of genetic information in each.

The addition of a chromosome is the more complex process, so I’m linking to an explanation of one mechanism by PZ Myers. Essentially, one chromosome’s worth of genes ends up being shared by two, and at first it can interact just fine with the old combined chromosome because the total sequence is the same. This does introduce a higher rate of error until individuals with the split chromosome start mating with each other, at which point there’s no longer a downside. Once the new number of chromosomes is settled, each chromosome is free to mutate independently and add new genetic information in the usual ways.

As for a reduction in chromosomes, we need look no further than our own genome. Our #2 chromosome pair is equivalent to two separate chromosome pairs in our closest ape relatives, but fused together. You can tell because there are two end markers (telomeres) right in the middle of it. No genetic information was lost, it was merely repackaged. This, importantly, is a very clear example of the kind of predictions one is able to make using evolutionary theory: the number of chromosomes in our genome compared to our ancestors’ (i.e. one less) tells us that exactly one fusion must have occurred, and we can then check the genome for only one extra set of markers.

And The Rest: You Finally Made A Monkey Out Of Me

Question:
If we evolved from monkeys, why are there still monkeys?

Answer by SmartLX:
Welcome to And The Rest, a potential new series where visitors and I try our best to create serious, concise, easy-to-understand answers to the most ignorant, misguided rhetorical questions and other hopeless arguments posed by theists who think they’ve got the ultimate trump card.

When you get one of these it betrays such lack of understanding and willingness to parrot propaganda that you may get angry and refuse to answer it; most of the time this will simply send the message that it works as rhetoric. I’d rather work on a library of straightforward answers which can be passed on and spread as wide as the questions themselves, until it’s inconceivable in each case that the question was ever given merit by anyone.

Right then, the monkey question is the classic example, so here’s my attempt to clear it up as quickly and simply as possible:

“Because not all the monkeys evolved into humans. Most of them evolved into other kinds of monkeys. They had different offspring like any family does. [Bonus semantics if you’re snarky:] And technically it was apes, not monkeys.”

Think you can come up with something more elegant? You’re probably right, so have a go in the comments. Otherwise, comment with some other faux “stumpers” we should cover in this series. Cheers.

If Evolution Is True…

Question from Josh:
If evolution is true,why did an EVOLUTIONIST admit that Archaeopteryx was/is a PERCHING BIRD!?

Also,what about the sabretoothed herbivore,or the fact that Trilobites have such perfect vision that there was no distortion (at ALL!)?

Answer by SmartLX:
Archaeopteryx is indeed currently classified as a bird rather than a dinosaur. It’s still descended from dinosaurs or other reptiles, which is obvious because despite its birdlike characteristics putting it over the line it’s still replete with reptilian characteristics. Its common ancestor with dinosaurs was just a bit further back. This has no bearing on whether evolution is true, except that it makes sense in light of it.

Tiarajudens was indeed a herbivore with a pair of “sabreteeth”. We know it ate plants because the teeth around it are well suited for the purpose of grinding plant matter. The big fangs would either have been a holdover from a carnivorous ancestor or a useful defence and deterrent against its contemporary predators. This has no bearing on whether evolution is true, except that it makes sense in light of it.

Trilobites had highly advanced eyes, developed at great speed as a primary tool for hunting food and avoiding predators (and therefore a major “selection pressure”).

One type of trilobite-style eye
One type of trilobite-style eye, courtesy of Wikipedia

The trilobite-style eye evolved quite separately from the eye we see in mammals and reptiles today; since it was adapted for use in water, it wouldn’t be much use to us anyway. Some of its components, for instance the signalling system, had already existed for millions of years in lifeforms as diverse as protozoa, plants and yeast. Some trilobites effectively lost their eyes over time because they were living so deep underwater there was no light to speak of. This has no bearing on whether evolution is true, except that it makes sense in light of it.

From Soup To Fish

Question from Wilson:
I am not an expert in biology just warning you, so feel free to enlighten me!

Correct me if I am wrong but evolutionists believe that life originated from a soup filled with amino acids or something along those lines. But there are a whole range of complex and simple microorganisms each with precise roles and functions almost like a program? And correct me again if I am wrong, now the cells function in a certain way due to a specific set of instructions in their DNA…how do you explain the exact precise instruction that each one of these different microorganisms have without there being an intelligent creator…finally I am also wondering how a bunch of amino acids decided to come together to make a microorganism and how that tiny cell decided itself that it needs to reproduce and how the heck microorganisms turn into a fish without a creator and if you’re gonna use time as an answer then what is the probability of such an event occurring for even a simple cell?

(Just as a lot of atheists find the idea of God absurd I find Evolution completely absurd)

Answer by SmartLX:
I’m not an expert in biology either, but a little research in response to things like this can teach you a lot, and I’ve been at it for a few years now. I’m still learning of course; while I write these answers I’ve usually got multiple other tabs open for reference material.

Before I go into details, the same logical problem applies here as to the last question I answered: the argument from ignorance. That’s not an insult, it’s the proper name for a specific fallacy where because you personally don’t know how something could happen, you assume it didn’t. Even if I had no answers for any of these, we would not be justified in jumping to the conclusion of a god until any other possibilities were not just dismissed but actually ruled out (or at the very least, actual probabilities were assigned to them).

I’ll try to address each of your points, but each of my points may not correspond to just one of yours or to the order of yours.

– There are multiple hypotheses about the origin of life from non-life (abiogenesis), and the “primordial soup” idea is one of the classic front-runners. Here’s a list of the current ones.

– Amino acids could occur naturally, as was demonstrated in the 50s, but a lot of different amino acids and other materials had to come together in just the right way to make the first simple proteins and genes. That’s a big factor reducing the probability that it would happen. However, there are three factors of a comparable scale which raised the probability: the sheer amount of material being constantly shoved against itself by natural forces, the huge number of different combinations that could have had the same effect, and finally the vast amount of time you mention – by current estimates, about one billion years from the formation of the Earth to the emergence of the first life form.

– The first life had DNA, or an equivalent like RNA, with one simple instruction: “Use the material around you to make another of yourself.” This was not an intelligent command, it was just something its physical makeup drove it to do, like a pinwheel spinning in the wind because of its shape. If it was in an environment full of the same material of which it was made, then this was straightforward: break evenly in two, then have each half absorb its own weight in raw material, then repeat. This is how microorganisms still do it today.

– Once life existed and was able to reproduce, it began to diversify. Slight imperfections in the self-copying process produced different offspring, and some of those differences were carried forward to the next generation. Whichever differences made it easier to survive and procreate, the creatures with those features tended to grow in number relative to the others. At some point a set of single-celled organisms joined together and shared their genetic material; the experiment was successful, and the first multicellular life came about. (Perhaps it had occurred before, but in the wrong conditions, and everything that tried it died.) At a certain point, small amounts of calcium became part of the essential material in the “body”, forming rigid structures; this helped with self-defense, and the viability of bones was established. Every tiny change that came about had to compete with other changes and come out on top, so every change that persisted had to have some benefit (or at least not be a hindrance), and thus a number of useful features began to accumulate. It’s been so long now that living things and their genes seem to be made of nothing but useful features, though some superseded components (like the appendix) have yet to be eliminated entirely.

I recommend reading at least a couple of books on evolution, just so you can know what the theory actually says before deciding whether it’s so unlikely. Your Inner Fish by Neil Shubin is about to be accompanied by a TV show. Richard Dawkins’ early book The Blind Watchmaker is a great primer, and has little or none of his recent anti-religious material that puts believers off him. Just don’t restrict yourself only to books on evolution by creationists and/or Intelligent Design proponents, because all they do is claim that various things are impossible when at worst we just don’t know how they happen – and sometimes when we actually do know.

The Human Body: The Amazing Multitudinous Dichotomy

Question from Robert:
Message: To whom it may concern: How can you explain the amazing complexity of human beings? The average human body has between 75 to 100 trillion cells. If no God, how could trillions of cells, which have no brain, collect themselves together and then change into all the highly specialized cells of the human body?

Also it takes a man and woman to create a baby. Therefore, a male and female body would have had to evolve at exactly the same time~! And a hermaphroditic human being still poses the same problem. The male and female parts would have needed to evolve — AT THE SAME EXACT TIME~! That is absolutely impossible.

Answer by SmartLX:
Didn’t actually go looking for answers to these, did you? You immediately took them to be ideal rhetorical blunt objects to beat any “Darwinist” into silence. The second one isn’t even a question, and you claim it’s impossible; this is not the language of someone who genuinely wants to know. Even if there were no answers to either one, to assume that there is no possible explanation without actually ruling any out is an argument from ignorance. Thing is, there are quite reasonable answers to each.

Today there are plenty of living things with no brain, and they assemble themselves just fine. Even the creatures with brains must start their self-assembly before the brain is formed, so brains have little or nothing to do with it. One cell automatically divides into two, then four, then eight and so on, held together with membranes. The DNA contained in each and shared by all contains the necessary information to allow each of these “stem cells” to metamorphose into a skin cell, a brain cell, a liver cell or whatever is needed. The cells can send biochemical signals to each other, so for example a cell is informed that there are enough lung cells for the moment and it becomes a bone cell instead. Once enough of an organ has come together, it reflexively begins its specific function: the brain manipulates electrical energy, the kidneys process liquids, the bones produce blood cells.

As for why there are so many cells in a body, there are many factors that limit the size of a living thing but for us none of them really kick in until the trillions. There’s enough food to feed them, they’re light enough not to collapse under their own weight, they’re strong enough not to break apart without significant force. There are obvious advantages of having so many of them together, too: they can defend themselves against similarly large threats, huge numbers of cells can be cut away or killed while the rest survive, they can reproduce fast enough to replace short-lived cells like skin cells. Once early single-celled organisms first fused together and shared their DNA about one billion years ago, there was nothing to stop them from amassing more and more cells per organism for all that time. Exponential growth has led to the huge conglomerates that are modern plants and animals.

In the same fashion that cells differentiate into many different types, the human body as a whole is triggered by its chromosomes to specialise as one of two types, male or female. (Sometimes this goes wrong: the body gets mixed signals and you get intersex babies, or hermaphrodites.) In our evolutionary history this would have started as a much less pronounced difference between two groups in the one microscopic species. Importantly, they remained part of the same species because they exchanged genetic material directly, perhaps by simply pushing it through their cell walls. It immediately conferred an advantage in terms of survival and procreation because the DNA of every new offspring was a recombination of two sets instead of a clone of just one. More new combinations, more mutations and overall faster evolution. (This effect has been observed directly in adjacent populations of small fish, some of which reproduce heterosexually and some unisexually. The ones who have sex with each other build immunity to new diseases in fewer generations.) Once that was happening, the differences within the species were free to develop further, and a similar distinction was already present in every other species that descended from it.

Picking various amazing things about the body (or our planet, or the universe) and claiming they’re unachievable without a god is a terrible way to logically arrive at the necessity of a god, partly because of the argument from ignorance but mostly because there’s usually been a lot of work done to determine the method and it’s liable to be plonked in front of you. This approach is however an excellent way to reassure believers, who are less likely to research a claim that supports their beliefs, that they are justified in their faith. Consider the possibility that this is the spirit in which these ideas were conveyed to you, because they just plain don’t work on atheists.

Three Ducks In A Row

Question from Bryson:
1. Based on Mendel’s work, only genes, not physical acquired traits are passed to the next generation. Now, based on that, what mechanism in nature creates new genetic codes to build an improved animal? None that I know of. none that Richard Dawkins himself can think of as when asked he had no answer. So there would be no inheritable variations for natural selection to choose from. Now I know that some evolutionists have mutation as the answer. But mutation only damages DNA, it doesn’t produce new information and as proved by scientists, there’s no beneficial mutations in existence.

2. Also the Cambridge discovery. The oldest fossils ever found on earth, showing different species of the same “family” suddenly appearing at the same time with no links connecting them. Everyone says evolution is proven fact, when in actuality, evidence is extremely rare, and highly inconclusive at best.

3. Also, when scientists tried, they found that even on paper, you can’t take a cell below 200 genes. And in 06, they concluded in reality, it actually is impossible to go below 397 genes. A cell needs a certain amount of things to live. Scientist call this the minimal gene concept. Well…to find the origin of life you would have to go down to 0 and build up.

What is the atheist response to this?

Answer by SmartLX:
Three very old creationist canards. The word is appropriate because it defines them as unfounded, and slightly funny because it’s also the French word for a duck. I’ve numbered them for reference.

1. Gene duplication, transposable element protein domestication, lateral gene transfer, gene fusion/fission, de novo gene origination, and probably more. Several of these happen during mutation. The Lenski E.coli experiment, despite what Conservapedia has claimed, is a pretty clear-cut example of a positive mutation directly observed. Richard Dawkins wasn’t dumbstruck because he didn’t have an answer, he was furious because the nature of the question made him realise a pair of creationists were in his home under false pretenses. Here’s his explanation of the event. Even if you don’t believe his account, in the same piece he gives a complete answer to the question, and it stands on its own merits.

2. Fossils are rare to begin with, but when you go all the way back to when animals didn’t have skeletons or hard shells of any kind, there are hardly any at all. I’m not familiar with the specific “discovery” you refer to (link to it if you like), but that’s generally why fossils appear to start off already diversified. It hardly matters when we share more than half our genome with all animals and even certain plants, indicating a common ancestry.

3.The “minimal gene set” is a few hundred proteins, not genes, and it was easier for them to come together when they did than it would be now. Naturally occurring amino acids were all over the world and throughout the sea, and there was no other life to consume them or otherwise interfere. The chances of the specific protein set coming together were tiny, but this was more than balanced out by the vast amount of space, materials and time the chemicals had to get it right, and also the number of different possible combinations that would have had the same effect. And of course it only had to happen once.

Evolution and the Holocaust

Question from James:
Hey thanks for reading this. If evolution is survival of the fittest then why was Hitler considered evil? If he could overcome the Jews then Germans must be better then Jews. In fact racism shouldn’t be a bad thing if you truly believe your race is better. Also why does it matter is animals go extinct? I get cows and animals we use, but who cares about obscure fish and bugs?

Answer by SmartLX:
Your initial question about Hitler is like asking, “If the atomic number of boron is 5, why did two different actors play Darrin on Bewitched?” The first part is true and so is the second, but the two are unrelated.

Evolution is an explanation of what has happened, over the entire history of life on earth, to change it from a single population of similar single-celled organisms to the vast complexity and diversity we see today. “Survival of the fittest” is still an apt simplification, because at all times those organisms which are more fit for survival and procreation are the ones that pass on the most genes. Some kill members of their own species to get along, some don’t have to. Even Darwin thought it was pretty brutal, writing that “nature is red in tooth and claw,” but human morality is difficult or impossible to apply to non-human animals. They’re just doing what their instincts tell them.

Evil on the other hand is a label we apply to actions and people who go against our morals and ethics. Hitler’s genocide violates the morality of such a huge majority of us that society as a whole can label him evil without fear of being challenged. That the act was intended to benefit Hitler’s chosen race does not make it good or ambiguous just because this sounds vaguely evolutionary, because there is no morality to evolution. Evolution is just what happened, take it or leave it, and our morals as applied to Hitler come from other sources.

The Holocaust comparison fails on other levels. Here are two.
– Despite the claims of Nazi propaganda which tried to dehumanise the Jews, the Holocaust boils down to a single species attacking itself en masse, which isn’t good for any population. So does any act of ethnic cleansing, which is why racism is unsupportable by evolutionary theory. If anything the Holocaust could be seen as an act of “social Darwinism“, which borrows the terminology of evolution but has little in common with it.
– The six million Jews were murdered in an act of artificial selection, not natural selection. Evolution has no will and no goals, but Hitler decided those Jews should die. This deliberate culling has far more in common with techniques that have been used in animal breeding for centuries, long before Darwin.

Moving on, we actually don’t care very much about fish and bugs, do we? The former we catch live, kill painfully and eat with relish, and the latter we crush on our forearms without a second thought. Fish and insects are alien to us, so it’s hard to empathise with them – especially the insects, as we can’t really look them in the eyes. Once you get to mammals like cows and pigs, we’re still happy to eat them but we start to care whether they are treated humanely on the farm and in the abbatoir. We perceive cats, dogs, apes and monkeys as so like us in behaviour and attitude that most of us wouldn’t even consider killing one, let alone eating it. This empathy is where we get the urge to protect animals and treat them well, rather than some platitude about them all being “God’s creatures”, but there is a sliding scale of how strongly it applies.

That wasn’t really your point though. If you want an evolutionary rationale of why we should prevent obscure species from going extinct, animals that wipe out other animals or plants completely usually do themselves a terrible disservice in terms of survival. They deprive themselves of a food source, or a crucial nutrient is lost which leaves them susceptible to disease, or they allow a new poisonous species to flourish, or they put themselves at war with some other animal that was dependent on the late species. All of the above might apply to us, but additionally human science and medicine might have all sorts of uses for species of any type. Finally, although we can’t muster much empathy for alien-like species while they suck our blood or whatever, the fact that they’re just trying to survive too does engender a broad sense of solidarity with all living things.