Topics related to animals and veterinary medicine
Evidence against evolution
- May 9, 2017 at 12:38 #1160
We have many “evidences” that support evolution – fossils, body structure, embryonic development etc etc. Is there well accepted “evidence” against evolution? Can anyone explain it.
- May 9, 2017 at 13:37 #1164
I am posting some discussions where people had discussed about this issue –
Darwin said only the strongest survive.
This is actually untrue, and a common misconception about Darwin’s theory of natural selection. Darwin’s theory is often summarized as “only the strongest survive” or more commonly “survival of the fittest”, but these oversimplifications completely misconstrue Darwin’s theory.
Darwin’s theory of natural selection revolves around three ideas:
Variability of various traits amongst organisms in a population
Heritability of these traits
Differential reproductive success – the ability for organisms in a population to reproduce at different rates of success
There is also the idea of fitness. Fitness is actually a term with biological meaning – it refers to the ability of an organism to reproduce. An organism is said to be more “fit” than another organism if it has a greater chance of reproductive success or producing more offspring than the other organism.
Therefore, Darwin’s theory indicates that the ability for certain organisms to reproduce more than other organisms in the same population (differential reproductive success) is more important than the survival of these organisms. Survival is actually irrelevant, besides to the extent it allows an organism to successfully reproduce.
This means that traits that are more likely to lead to the greatest reproductive success are those that are most likely to be passed down. Even if other species were stronger or smarter than humans, those traits are irrelevant if they didn’t help them gain additional reproductive success.
Sometimes we see traits that aren’t great for survival being passed down. An example is a male parrot’s bright colors – they aren’t great for survival (as predators easily notice brightly-colored parrots), but parrots with bright colors have an increased chance of attracting mates, so they have greater reproductive success. This is an example of Sexual selection. This once again illustrates the idea that it’s not always the strongest or most likely to survive that succeeds – it’s the organism with the most fitness.
The reason humanity survived is not necessarily because we were stronger or smarter, it’s because we had more reproductive success.
I would highly recommend reading a copy of Darwin’s book, The Origin of Species. It definitely helped me understand evolution and natural selection a lot more, and cleared up many of my misconceptions about it.
Darwin said only the strongest survive.
No, he didn’t. This is a false belief clung to by people who have never read Darwin and never taken a class in evolutionary biology. It is as false as someone saying “Jesus said we should execute bankers.”
Darwin said the most reproductively fit transmit their traits to the next generation. Reproductive fitness doesn’t necessarily have anything to do with strength.
According to evolution homo sapien sapiens(us) were not the strongest homo species. We were likely only slightly smarter than homo Neanderthals. And other humans like Homo heidelbergens and Homo floresiensis were physically stronger. What made us survive?
We had advantages they didn’t.
We reproduced faster. We worked together cooperatively (and the ability to work cooperatively is a huge, huge boost to reproductive fitness). We developed complex abstract language, which is an enormous boost to cooperative endeavor.
The idea that you have to be physically strong in order to survive is completely, utterly wrong. Jellyfish are not strong. They seem to be doing pretty well.
Well this is a rather confused argument against natural selection.
First off, no as others said Darwin did not say it is the strongest who survive. There are plenty of animals that aren’t physically strong and thrive quite nicely. The confusion here might be due to modern language, Charles Darwin when he said “fittest” did not mean “fit” as in “physically impressive” he meant it as in “healthy and fertile.”
What Darwin has stated is that it is not the strongest who survive, nor is it the smartest, it is the most adaptable. One guarantee for survival is to make lots and lots of young. Humans may not be the strongest species but we are pretty solidly adaptable considering the only place on Earth lacking permanent settlement is Antarctica but that’s only because of international agreements.
Human communities have a very fascinating tendency to survive whatever nightmares nature throws at them. Meanwhile individuals can have an almost unnerving determination to do something and succeed. That’s rare in the animal kingdom, and it’s been one of the dominant factors in humanity’s conquest of the planet. The only animals that come close to this level of conquest are considered pests.
Intelligence is a tricky thing to both grasp and use, funnily enough. Even among humans those considered very intelligent can struggle to actually achieve their full potential and the reasons for these can be many. While it is possible that Neanderthals were smarter in some areas, intelligence alone only takes you so far. There is suggestion that while Neanderthals had slightly larger brain-cases, they might have lagged behind the advanced social skills of homo sapiens.
There’s also the hypothesis that neanderthals and humans might have intermingled, and that most modern humans have some neanderthal genes.
As for strength compared to other humans? Again, it’s not everything. I can think of plenty of similarly-sized yet stronger animals, and while heidelbergens might have been around the 1.75m range, they also tended to weigh on average 60kg, that’s close to underweight for a human male that size and since muscle tends to be denser than fat, its debatable if they’d have more muscle power.
As for floresiensis? It’s difficult to believe they’d be stronger when they averaged the height of a small child.
To be physically capable of taking on ancient humans (who would measure between 5′ 3″ and 5′ 7″) would be interesting to see considering an adult homo sapian would have twice the reach, twice the leg length and about double to triple the mass.
Now what might be our advantages? Well how about this:
You know how people love to put all sorts of things like pepper, cumin and cinnamon on our food? How we will ingest large quantities of chocolate and pistachios and only feel ill if we really gorge ourselves? Or how about the cultural fascination with breeding ever spicier chilli peppers?
The plants all these things came from evolved all those wonderful tastes for self defense. We use those defense mechanisms to enhance the taste of our food. And while horses and wolves can easily overpower most humans, said humans have an almost Wolverine-like ability to recover any broken bone with the right medical care.
Just contemplate these.
NO, Darwin did not say only the (physically) “strongest survive”.
Before anyone says something goes “against Darwin”, don’t you think you should read Darwin.
This is what Darwin wrote:
“If, during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organization, and I think this cannot be disputed; if there be, owing to the high geometric powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each beings welfare, in the same way as so many variations have occurred useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will will tend to produce offspring similarly characterized. This principle of preservation, I have called, for the sake of brevity, Natural Selection.” [Origin, p 103 6th ed.]
Nothing about physically “strongest” is there?
The phrase “survival of the fittest” is a soundbite version of natural selection. It was coined by a man named Herbert Spencer. Darwin did use the phrase when he summarized natural selection a couple of pages later:
“This principle of preservation, or the survival of the fittest, I have called Natural Selection. “
So, it is survival of the fittest, not “strongest”. Physical strength is a way to be fitter. Sometimes. But there are other ways to be “fitter”. Smarter is one. More cooperative is another. Better language ability — in order to cooperate better, is another. Being able to exploit more food sources (such as rabbits and squirrels) is another. The ability of H. sapiens to hunt and kill smaller animals like rabbits has been proposed as one reason we out-competed H. neanderthals. Another is H. sapiens ability to be a long distance runner and run prey to ground. Neanderthals were adapted to withstand cold, not to run.
This question shows that although some don’t accept evolution, a Strawman can clearly evolve from primordial bullshit slime in just a few hours.
The argument Darwin made was that any strategy which worked was proved fit, and nature then selected for it. This has nothing to do with strong. We are not talking about fitness in the sense of push-ups, cardio and running around the football field.
“Fitness” here means suitability to the task at hand. It turns out that mother nature is a little bit promiscuous and she will hand out her bounties to any organism that can demonstrate the ability to get on with the job. The job being surviving and making offspring.
On a specific point of fact, Homo Floresiensis was about 3′6″ on a good day, and was probably trapped on a single island ecosystem. So we can probably dispute the bit about being “physically stronger”.
Although I am no pugilist, even I could take down one of them hobbity little feckers.
Big Important Thing #1:
Charles Darwin never said “Only the strong survive.” A more accurate quote is “survival of the fittest,” and this in fact didn’t even originate with Charles Darwin, but another biologist: Herbert Spencer.
Big Important Thing #2:
You’re confusing physical strength for reproductive fitness and survivability. Evolutionary fitness isn’t a measure of how many push-ups you can do. It’s a measure of how good an organism is at making copies of itself and having those offspring survive to adulthood. While physical strength is generally a desirable trait, it is far from the only thing to consider here.
Not Terribly Important Thing:
I’m highly skeptical of your claim that Homo floresiensis was stronger than Homo sapiens. Where did you get that?
And the rather disappointing answer…
We don’t know exactly why our species is the one left standing today. It may have been luck, disease, climate change, tool technology, culture, or a combination of this and any one of a dozen or more other traits. We do not have anywhere near sufficient archeological evidence to reconstruct the waxing and waning of populations of these homini
Darwin said only the strongest survive.
He said nothing of the kind. Such a theory would have been laughable. It would be inconsistent with the existence of (to pick a random example) ants. By some estimates, ants make up ten percent of the total animal biomass of the planet. Darwin was clearly aware of the existence of ants, and finches, and tortoises, and any of a wide variety of other animals that he saw on his voyage aboard the Beagle.
Indeed, Darwin was keenly aware of certain peculiarities with respect to ants. For instance, it is well known that ants and aphids can share certain symbiotic behaviors that benefit them both. Here is an excerpt from Origin of Species, where Darwin talks about that:
One of the strongest instances of an animal apparently performing an action for the sole good of another, with which I am acquainted, is that of aphides voluntarily yielding, as was first observed by Huber, their sweet excretion to ants: that they do so voluntarily, the following facts show. I removed all the ants from a group of about a dozen aphides on a dock-plant, and prevented their attendance during several hours. After this interval, I felt sure that the aphides would want to excrete. I watched them for some time through a lens, but not one excreted; I then tickled and stroked them with a hair in the same manner, as well as I could, as the ants do with their antennae; but not one excreted. Afterwards, I allowed an ant to visit them, and it immediately seemed, by its eager way of running about to be well aware what a rich flock it had discovered; it then began to play with its antennae on the abdomen first of one aphis and then of another; and each, as soon as it felt the antennae, immediately lifted up its abdomen and excreted a limpid drop of sweet juice, which was eagerly devoured by the ant. Even the quite young aphides behaved in this manner, showing that the action was instinctive, and not the result of experience. It is certain, from the observations of Huber, that the aphides show no dislike to the ants: if the latter be not present they are at last compelled to eject their excretion. But as the excretion is extremely viscid, it is no doubt a convenience to the aphides to have it removed; therefore probably they do not excrete solely for the good of the ants. Although there is no evidence that any animal performs an action for the exclusive good of another species, yet each tries to take advantage of the instincts of others, as each takes advantage of the weaker bodily structure of other species. So again certain instincts cannot be considered as absolutely perfect; but as details on this and other such points are not indispensable, they may be here passed over.
I’d suggest that actually reading The Origin of Species may be illuminating.
Doesn’t humanity’s very survival go against Darwin’s Natural Selection theory?
Darwin said only the strongest survive. According to evolution homo sapien sapiens(us) were not the strongest homo species. We were likely only slightly smarter than homo Neanderthals. And other humans like Homo heidelbergens and Homo floresiensis were physically stronger. What made us survive?
Actually, Darwin didn’t say “only the strongest survive”. It was Herbert Spencer that said it, and even he didn’t use that phrase. What he said was, and I quote:
“This survival of the fittest, which I have here sought to express in mechanical terms, is that which Mr. Darwin has called ‘natural selection’, or the preservation of favoured races in the struggle for life.”
Darwin liked the phrase, and used it in his book The Variation of Animals and Plants under Domestication. In the fifth edition of On the Origin of Species, he introduced it meaning “better designed for an immediate local environment”.
True, we weren’t the strongest homo species. But then again, as we see above, it’s survival of the fittest, not the strongest, and better designed for an immediate local environment.
This meant the brain. Ours were the brain more adaptable, more inventive, capable of abstraction on a level that neanderthaliensis or floresiensis did not achieve. We had a brain that could invent tools that let us overcome our lack of strength.
That made us survive.
Evolution has nothing to do with the origin of life.
Read it again until you get it.
Evolution has nothing to do with the origin of life. Evolution has nothing to do with the origin of life. Evolution has nothing to do with the origin of life.
Evolution describes a process of differentiation and speciation after life has gotten started. It says nothing about how it started. The question of how it started is “abiogenesis.”
But don’t feel bad. Confusing evolution with abiogenesis is a common Creationist mistake. Your preacher made that mistake, so you did too.
Why should we take evolution seriously? Because a mountain of evidence supports it. Literally the entire modern understanding of biology rests on a foundation of evolution. Evolutionary biology is so well supported by so much evidence that it underpins all of modern epidemiology, medicine, zoology, botany, taxonomy, immunology, molecular biology, you name it.
As evolutionary biologist (and devout Christian) Theodosius Dobzhansky said, “Nothing in biology makes sense except in the light of evolution.” You might not like it, but the real world doesn’t care what you like. The evidence is enormous.
It needn’t have been spontaneous, and could have occurred in stages
The probability of this happening is not “ridiculously small”, and there’s plenty of evidence to suggest that it’s over 50% in conditions known (from the geological record) to exist on an early earth
We may never know the exact details of what happened, it’s not as though tiny individual molecules leave fossils!
The above points are irrelevant to evolution anyway… as the process of evolution was first documented before we even knew of genetics, and only concerns itself with what happens once life already exists. The origin of that life and nucleic acids more correctly falls under the domain of abiogenesis. One possible source of confusion here is that Darwin’s book is titled “On the origin of species”, but it only describes how a new species might arise within an existing ecosystem, not the origin of all life.
Evolution is not something that one believes in, any more than one “believes” in gravity. As with gravity, beliefs and theories do exist in the field of evolution, but they relate to specific details, not to whether or not it exists in the first place!
Even if the probability of something is “ridiculously small”, given enough time, or enough attempts, it will happen
The probability of an event that has already happened is 100%
The probability of everything is small except when it has already happened.
First, in direct response to your question: Carbonaceous meteorites contain a wide range of extraterrestrial nucleobases
So, we know they can form in space -or possibly when a meteor hits our atmosphere and heats up. Either way, the odds of them being formed in space is 100%. They might form on Earth as well in other ways.
Now, to go deeper and look at probabilities. The odds of you, or I existing are tiny. Let’s use me as an example, but accept that I am generalizing. My parents were from a small town but did travel somewhat. Let’s say the odds my father chose my mother were one in a hundred. The same odds for my mother choosing my father. We are now at one in ten thousand (100 X 100). They each had parents [(100 X 100) X 2] or 100 to the power of 6. Twelve zeros. 1 in 1,000,000,000,000. They each had two parents means we add 4 X 2 zeros. They each had parents: 8 X 2 zeros. This is a mere four generations and we are at 36 zeros. At between nine and ten generations, we reach a thousand zeros. One over (one with a thousand zeros following).
The odds of me being here. 100%. The probabilities only work for the future, for predictions.
You didn’t specify one specific molecule and I am torn whether this improves the stats or not. You are also entirely free to state that I offered evidence for one (or a few) molecules but not how they form the chain that carries instructions for building living things. I entirely agree. But you didn’t ask for that.
I want to change your question: How can anyone still believe in evolution when evidence and probabilities for necessary molecules are so small?
We need to look where the evidence is and not where it isn’t. The probabilities seem low and might in fact be low but the lack of evidence for molecules is not a surprise. There are no fossil molecules. Bones and other large structures can fossilize and leave evidence but individual molecules typically do not.
As for fossils, it is a verifiable fact that few things fossilize – this is not a plea or excuse for the state of the evidence. We know, for example, that billions of passenger pigeons existed in the USA. Now they are gone and there are no fossils of any. Not one. Few things fossilize. Fact.
The fossils we do have show transitional features and, for example, the transition form sea to land for vertebrates is wonderfully clear.
With regard to molecules, we don’t have fossil molecules, but we do have shared genes and DNA that are best explained by a common ancestor. How did DNA form and become the code that allows evolution to happen. I don’t know. I don’t think anyone can offer a complete view of how it happened. Do humans share DNA of viral origin with other apes? Yes, we do. The best explanation for this is that the DNA was inserted into our common ancestor before we branched off from other apes. There is more than one such viral insertion and they all appear as predicted by evolution.
First, as several people have pointed out, the question is about abiogenesis, not evolution. Evolution presumes life exists. Sigh. It would be nice if people actually read Origin of Species. At the end you find this paragraph:
“There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.” C. Darwin, On the Origin of Species, pg 450.
This makes it very clear that evolution happens after abiogenesis.
Second, it is easy to get abiotic synthesis of nucleotides, the monomers of nucleic acids. It is also easy to get abiotic polymerization of RNA (which is a nucleic acid).
Abiotic synthesis of RNA in water: a common goal of prebiotic chemistry and bottom-up synthetic biology
DNA can be made by a different route. It is very easy for amino acids to polymerize abiotically to form proteins. 2 common methods is drying out in a tidal pool or at a hydrothermal vent. Both have been done in recreations in the lab. Now, when the tide comes back in or the proteins move to cooler water, they spontaneously form living cells. These are called “protocells”.
Snyder WD and Fox, SW. A model for the origin of stable protocells in a primitive alkaline ocean. BioSystems 7: 222-229, 1975.
Yanagawa, H. and K. Kobayashi. 1992. An experimental approach to chemical evolution in submarine hydrothermal. systems. Origins of Life and Evolution of the Biosphere 22: 147-159. (protocells at hydrothermal vents)
Some of the proteins in protocells will catalyze the synthesis of DNA from nucleosides:
JR Jungck and SW Fox, Synthesis of oligonucleotides by proteinoid microspheres acting on ATP. Naturwissenschaften, 60: 425-427, 1973.
Once you have the RNA and DNA inside protocells, evolution will produce directed protein synthesis.
These experiments, and others, have shown that the probability, instead of being “ridiculously small”, is actually one. Virtually certain.
Original question: How can anyone still believe in evolution when probabilities of spontaneous generation of nucleic acids is so ridiculously small?
I’ll leave aside the difference between evolution and abiogenesis and the overwhelming evidence for evolution, because other answers have covered them well.
What’s not been addressed is whether the probability of spontaneous generation of nucleic acids is ridiculously small.
Certainly, the odds that if you put a few hundred billion atoms in the right proportions in a box and waited they would suddenly organise themselves into DNA are vanishingly small.
But what about the odds of a smaller number? How about 30–40? Not so unreasonable?
Because that’s what you need to make a nucleic acid. Here are pictures of deoxy ribose adenine phosphate and ribose uracil phosphate. I picked uracil because its the one that’s in RNA but not DNA, and it seems most likely that RNA formed first:
Image courtesy of drcruzan.com: Nucleic Acids
You can count the atoms: every letter is an atom, and every unlettered node is a carbon atom. Note also that most of the atoms in each molecule are in rings. Those rings are very stable – which means they have a much lower energy state than other ways those atoms could be organised, which in turn means they are likely to form. That ring shape is characteristic of carbon chemistry, and left to its own devices carbon tends to form rings and sheets of rings.
So, if you know a little organic chemsitry, the idea that something that simple could form spontaneously is not just plausible but it actually flips over to the point where it seems more improbable that it wouldn’t form given the right conditions.
But wait: it might be easy to make one of these, but one’s no good, right? DNA isn’t a single molecule of uracil or adenine, it’s billions of them all joined up. Surely that’s more implausible?
Because the amazing thing about nucleic acids is that they love company. The whole reason DNA and RNA work as information carriers is that other things love to stick to them. In particular, the cross with the P in the middle on the left is a phosphate group, and it can join two groups together:
Even better, the C (cytosine) and G (guanine), and the A (adenine) and T (thymine) or U (uracil) groups attract each other. That’s how DNA replicates itself, and why it’s a double helix.
So what we have is:
A small number of atoms form into a shape that is a very plausible shape for them to form
Once in that shape, the molecule joins up with other like minded molecules for fun, friendship and maybe more
Once they’ve done that, they can attract even more molecules and build a mirror image of themselves, which can in turn build an exact copy of the original string
It also so happens that other small simple molecules – amino acids – like to bind to nucleic acid. And when they do, they join up into bigger molecules called proteins.
The thing is, once (1) has happened, (2) and (3) are more likely to happen than not. It doesn’t need anything extraordinary.
Once you have a molecule that can replicate, a little thought would tell you that that it will tend to dominate its environment simply because it can make more copies of itself. And if an error leads to another molecule that’s better at replicating itself for some reason, or that can create proteins that help it replicate, that one will tend to overtake the earlier one.
There are still things we don’t fully understand about abiogenesis, but we have a pretty good handle on how complex molecules can arise from simple ones.
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