Behavior May Influence Evolution 262
eldavojohn writes "Pending your beliefs about evolution, National Geographic is running an interesting article on the influences of behavior on evolution. The study supports the controversial idea that an animal's behavior in response to environmental change can spur evolutionary adaptations. By adding a predator to an island where a species of lizards lived with no predators, they witnessed a quick shift in the average length of legs on the lizards. Long legs meant to escape were useless against the new larger predators while short legs became the dominant feature since they increased climbing ability (to trees the predators could not reach). For the finer details on the research, visit the Losos Lab Research Page."
Will we adapt? (Score:5, Funny)
Could that imply that the behaviour of disbelieving scientific facts could spur a reduction in brain size in order to adapt to reduced intelligence?
Article is wrong - Study misinterpreted. (Score:5, Informative)
Not the submitters' fault, they simply read the article and based what they wrote on it.
Let me explain:
The article is claiming that "Evolution's Driving Force Shifts Based on Behavior"
Go to the actual research site (linked in submission), scroll down to the end, and you will find that what they're saying is:
"... another alternative is that lizards growing in different environments grow different length legs. To test this hypothesis, we raised baby anoles on two different surfaces at the St. Louis Zoo--either on 2x4's or on narrow (1/4") dowels. At the end of three months, the lizards raised on broader surfaces had longer limbs than the lizards on narrower surfaces! This suggests that the results observed in the field may be the result of a phenotypic plasticity in limb growth, rather than genetic differentiation."
Phenotypic plasticity [wikipedia.org] is a term some of you may be unfamiliar with, a good example of it is found in ants.
In any given hill, there are different castes of ants. Warriors, workers, etc. They are all quite different.
However, the differences are not genetic; they arise during development and depend on the manner of treatment of the eggs by the queen and the workers, who manipulate such factors as embryonic diet and incubation temperature. The genome of each individual contains all the instructions needed to develop into any one of several 'morphs', but only the genes that form part of one developmental program are activated.
This is what the study suggests is happening to these lizards.
They're saying there are at least two different 'morphs', one with long legs and one with short ones, in the genome of the lizards.
These are then selected between (through some so far unknown mechanism) based on the environment of the lizards.
"These findings suggest the intriguing possibility that phenotypic plasticity may play an important role in adaptive differentiation by permitting lizards to occupy different habitats; once subsequent mutations arise, these differences can then be elaborated upon by natural selection."
Now, let the ghosts of Lamarckism [wikipedia.org] the article has raised from their graves go to rest.
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Re:Article is wrong - Study misinterpreted. (Score:4, Interesting)
Phenotypic plasticity can only select between states already present in the genome. Activating a certain subset of genes, but not altering the genome as is required in Lamarckian evolution.
(Lamarckian evolution in a nutshell is generations of giraffes stretching their necks to reach the higher leaves, passing the added length they train through life on to their decendants)
What could (as far as I understand) be theoretically possible, is for males to "select" the sperm to produce from a set of phenotypes. Perhaps dependent on hormonal activity, etc. (Producing "warrior children" if they had been stressed, angry and afraid over a long period of time?)
Don't really know if it's possible, but it would give a distinct survivability advantage to be able to "devolve" the next generation back to an earlier phenotype if conditions were too harsh...
/. kisses up to pseudointellectuals article flameb (Score:2, Interesting)
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Link to one artic
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I'm not questioning evolution, I'm defending it.
Reread what I wrote. The article (at least the title, and the rest was way easy to (mis)understand that way) and the summary here was attacking evolution as we know it.
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The behaviour of disbelieving scientific facts is the RESULT of a reduction in brain size due to a lack of intelligent stimulation.
Why is this controversial? (Score:4, Interesting)
Are we not doing seeing this now in humans with antibiotics? Genetic manipulation?
How many people on Slashdot have said that the gene pool has become watered down due to the protections of civilization?
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I don't know that I've ever seen that before on Slashdot, but it's something I've been thinking for many years.
Re:Why is this controversial? (Score:5, Interesting)
Think about it: who is more likely to say 'fuck civilization': A person with perfect eyesight, or someone who needs that civilization to buy their next pair of contact lenses?
Re:Why is this controversial? (Score:5, Funny)
You must be new here.
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I personally believe it's more adaptation and survival of the fittest. I akin it to races among humans - darker skin of African or Middle Eastern people is an adaptation to the environment, but not specieation or evolution. Genetically, race != species, but the differences between all races of people are obvious ada
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Huh? You're making a distinction that doesn't exist. Evolution is the change of the frequencies of alleles within a population over time do to differential reproductive success of individuals. There are a lot of reasons for this differential reproductive success, but two biggies are being alive to reproduce (you didn't get eaten
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Of course it isn't really controversial at all, but labelling something 'controversial' gets publicity.
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Re:Why is this controversial? (Score:4, Interesting)
This discovery seems to me more "dangerous" for current science theories than current religions. It implies that will could have a different meaning than the mere transition of electrons in some areas of the brain. Down with Darwin, go Lamarck
It disproves the higher power Direct intervention in reality, sure. But didn't the predominance of an OS like windows have the same effect, or stronger? Anyway I didn't believe in it already, even if I believe in the possibility of a higher power being responsible for reality. If you think about it, imperfect creatures created by the higher power are much more problematic for theology than a higher power creating the universe, giving freedom to everything inside.
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So what are you suggesting? That "will" is somehow changing the DNA? Of course it isn't. This in no threat to Darwinism. All that is happening is that the lizards are moving into a situation where shorter legs are more favoured, so those with shorter legs are mo
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Actually, I just realized that an animal cannot evolve; only populations can evolve. For instance, there were always some combination of small-legged and large-legged lizards in the cited example. However, what has changed was the distribution of those sub-characteristics within the overall population.
What really gets me is what 'behaviour' has to do with anything when there is simply an environmental change.
Note that I think this is distinct from evolution by mutation, which is the actual addition of ch
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Do you:
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[cue Van Halen knockoff, doing "Soma's here / and the time is right / for dancin' in the streets" ]
Remember, Soma may not be a swift call for anyone interest
Why I Used the Word 'Controversial' (Score:5, Interesting)
Maybe you can argue that it was only natural for them to seek safety in the trees but I think that this study addresses something we must face. If you believe in evolution, you have to acknowledge that it's not only random genetics but also influenced by the behaviors of the animals granted those random mutations. If the lizards had behaved differently and not gone to the trees, perhaps longer and longer legs would have been developed until they were fast enough to outrun their predators. Or perhaps the species just would have been eradicated on the island.
Controversial because it implies that species may be able to subconsciously choose which feature is 'evolved' to be the dominant factor.
If you want to apply this to human evolution (as one is naturally only concerned with their own species), then I suggest you read Guns, Germs & Steel [pbs.org] by Jared Diamond. What I found interesting is that in some places, humans began a farming lifestyle earlier than other hunter-gatherers. It was this decision by way of discovery that led some civilizations to outpace others. In fact, the choice or 'discovery' of planting seeds and harvesting them periodically eventually led to some regions invading and 'colonizing' other regions. Can we call this evolution? Can we say that some evolution hinges on behavioral choices? I think we can, but that's why it's controversial because it has traditionally been thought that the dominant feature was only influenced by the environment--not by a choice made by the animal.
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Presumably if this paper is going to be in Science, evolutionary biologists think there's something especially novel to it, but I'm with the people who think it's obvious enough.
Incidentally, I know it's contrary to the way things are done here but the best way
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I supposed the lizards sometimes fled into trees if they had to even before this. Those who did + had short legs survived.
Also, everything about evolution is controversial? Is it really that bad in America?
Re:Why I Used the Word 'Controversial' (Score:4, Insightful)
Firstly Evolution is not always controversial, a massively insignificant minority occasionally try to cast aspersions upon it but this doesn't make it controversial.
Secondly I don't see the choices made by the lizards to live in trees rather than remain on the ground and be eaten by predators is any different to the way I understood evolution to work in general. The way I see it in this case living in the trees is more likely to make you live long enough to breed than continuing to live on the ground, animals with shorter legs are better at climbing trees and more likely to be able to get up them in time rather than their long legged cousins who get eaten. Does the article suggest that those animals with long legs don't take to the trees for their survival or that they do but are just not good enough at tree climbing to escape successfully ?
Basically it looks to me like the physical attributes of the animal are determining who is evoloutionarily successful and its simply the pressure of the enviroment which is creating a shorter legged species which prefers to run up trees.
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He's not talking about Christian fundamentalists, he's talking about scientists, biologists, geneticists, etc. If you think that they are in lock-step agreement about evolution, and they never disagree or argue or have controversies, you've never been to an academic conference. Case in point: punctuated equilibrium.
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I would say that we expect their to be disagreement about scientific theories and this is in fact the default position to take so for a scientfic theory of any kind t
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And punctuated equilibrium remains controversial to this
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This isn't true. Some species change very gradually, some
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That is a relatively minor debate. There is no question that evolution happens or that it is due to natural selection.
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Science which is not controversial might as well be religion.
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What you seem to be suggesting is that the anoles thought to themselves, "Hmm, we'd be better off with shorter legs, lets make our kids have shorter legs".
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Which is, of course, completely inaccurate.
From TFA:
"The change came sooner than expected. Just six months later the anoles were almost exclusively tree-dwelling, and longer-legged lizards had died in disproportionate numbers."
The average leg length in the population shifted because short legged a
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A new predator was introduced, altering the environment in which the lizard operates. Suddenly running away is less effective than climbing trees, so lizards with the tools and inclination to climb trees survive at a better rate in the new environment. Perhaps a naive observer might read some "decision" on the part of the lizards into this, but it looks like pretty simple natural selection to me. The instincts and behavioural patterns of
Re:Why I Used the Word 'Controversial' (Score:4, Interesting)
No. Really, it's not. It;s directly observable - you can see this from the experiment.
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Nothing controversial about that. If peahens didn't prefer to mate with showy males as a measure of fitness, presumably we wouldn't have peacocks.
No. This almost suggests nothing of the kind. The lizards tried to escape by climbing. Those with shorter legs were better climbers and were therefore "fitter" the lizards didn't sit around stroking their chins and devising a cunning new survival strategy.
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Precisely. This was clearly a behaviour used by the ancestral lizards when there were predators.
Uh - yeh, OK. So what's the problem? No controversy there.
What? That's just silly. Short legged lizards are better at climbing trees and survived It's as simple as that. Long legged ones could neither climb very well, nor run fast enough to escape. They were shit out of luck.
It's been a long time since I read it, but he makes a persuasive case that farming took off in certain regions because the natural wildlife were well adapted to being used as crops (large grain size etc.)
Nope. You can call it the predominance of a successful meme, if you want.
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Still there is nothing controversial (or even news) on what you said. There is a bit of news on TFA, but not on your interpretation.
And evolution is not controversial. It's even bettter accepted than such things as gravitation, or chemistry.
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One: behaviour is determined by evolution. Not entirely, behaviour can also be transmitted by culture, and invented by animals showing creativity. But generally behaviour is the work of the genes: try reading the Extended Phenotype (Richard Dawkins) for an understanding of how this works.
Two: to describe the anoles as "subconciously choosing" their evolution is anthropomorphising the critters somewhat. It looks to me like you have 4
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No, it implies no such thing. Behavior is a genetically regulated trait, just like leg length. So some anoles have genes that make them spend more time in the trees, while others make them spend more time lower down. Selection by predation alters the proportion of the genes.
What is more interesting about the article is that the long-legged phenotype first increased, then d
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No, because it IS only natural for them to seek safety in the trees. Or rather, all that needed to happen was for SOME to seek safety in the trees. There will be natural variability in the behaviour. What you are seeing is not behaviour influencing evolution, but the precise opposite - behaviour being selected by evolution. Without predators, tree-climbing would
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There is no controversy around a link between behaviour and evolution. That's pretty mainstream in evolutionary biology.
You don't understand the study itself, either. It's a fairly standard example of rapid evolution: predator kills more long-legged anoles than short-legged anoles, therefore more short-legged anoles reproduce, subsequently the proportion of short-legged anoles in the population goes up, which is the definition of evolution. Sure, the reason the short-legged anoles are more successful has
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The original poster is merely regurgitating the sentiment of the article, but they're both wrong about the "controversial" idea supported by the study.
All that the study suggests is that evolutionary changes can happen quickly when new selection pressures are applied, or, more importantly, when a group of thikning creatures takes a different approach to a problem (which may be a geneti
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The research page itself however, offers a completely different explanation:
"This suggests that the results observed in the field may be the result of a phenotypic plasticity in limb growth, rather than genetic differentiation." What they're saying isn't that the genes change, as the a
They're not evolving. They're like ants. (Score:3, Interesting)
A good example of phentotypic plasticity is found in ants. The different castes of ants in a hill are very different, such as workers and guards. This difference isn't found in their genes. Their genomes contain the molds for all the variations.
The eggs are treated differently, and this results in vastly different creatures coming out of the egg.
This is what the study suggests is happening, to a lesser degree, in the lizards.
The National Geographic article is wildly inaccurate.
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In the past 200 years (10 generations by conventional reckoning) the human population of Earth has increased more than six-fold.
This huge increase in population has been accompanied by virtually no selective pressure. We know that because "selective pressure" is a nice polite way of saying, "loads of people dying." Evolution operates via differential survival of different bloodlines, and
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Previous to the last 50 years there have been massively hi
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Far too many and they are all wrong. A diverse gene pool is a strong gene pool, over-specialization frequently leads to extinction.
Many... (Score:2)
"Watered down" has no real meaning. It is merely a sentiment that has no basis in facts. There is no way to "water down" a gene pool. You can't stop evolution by "protections of civilization." As long as individuals die and there is some differential in reproduction, evolution is happening. Sure, the evolutionary pressures and the source of mutations are changing slightly, but nothing is
Re:Why is this controversial? (Score:4, Funny)
And in other news... (Score:5, Funny)
Adaptations? (Score:4, Insightful)
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This isn't evolutionary adaptation - it's much more simple than that. If you start killing all of the lizards with long legs, the ones with short legs are going to mate and have offspring with short legs.
Isn't that exactly what the theory of evolution is?
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That's what the *article* is saying. Not the study (Score:3, Interesting)
What the study is saying is: "This suggests that the results observed in the field may be the result of a phenotypic plasticity in limb growth, rather than genetic differentiation."
Phenotypic plasticity is something we find amongst other thing in ants.
The various castes of ants (workers, warriors, etc) differ from eachother quite a bit. However, their genes are the same - Their genome holds the molds for all their various forms. Through diff
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Both aspects are needed for evolution to occur: The variation through mutation etc., and the differential selection.
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If you read the article, maybe you would wonder why the lizards didn't just keep growing longer l
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Yes it is. It that is exactly what evolution is, and how it works. While the adaptation may be small (and, to your mind, negligible) it is the gradual accumulation of millions upon millions of such small changes that results in all of the difference we see between extant species. If you keep up the pre
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It does say "Losos and his colleagues' work reported only on changes in the anoles over a single generation". Let's say Stalin kills off all intellectuals in Russia, so that the only Russians left alive are non-intellectuals. Would this provide evidence for evolution in Russian society? Of course not! To see evolution, you need to see multiple generations of the thing that's evolving.
Wh
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1. physically selection -- longer legs get selected
2. behaviour selection -- those who climb in trees get selected (those good climber have shorter legs which is opposite to first way of "adapting")
So, in this case, it seems that behavioral selection is more important than physical selection and that takes precedence and thus behavior influence the physical con
Controversial? (Score:5, Insightful)
Introduce a change to the environment that causes a behavioural change - is it so surprising that some members of the population are better suited to the behaviour than others?
Apropos nothing, it's pretty sad to see such a story headed with the words "Pending your beliefs about evolution" on a site such as Slashdot. Evolution is an observable fact. Evolution through natural selection is a massively successful and well supported theory.
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To the extent non-mathematical facts exist, Evolution is one. In the common parlance, we assume facts do exist. We consider those theories, (such as "the sun will rise tommorow") whose evidence passes an extremely high level of confidence, to be facts. Evolution is amongst these. We have gathered the evidence that makes us so sure about Evolution by making observations; others who make all those same observations should also be sure. Hence I feel it is entirely reasonable, and even desirable, to descri
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No, he was noting correctly that actual evolution of humans hasn't been observed. I think that he missed (which I thought was part of your point) that all the aspects of evolution have been observed to some degree and hence are facts in themselves."
Both are reasonable interpretations of his original post, and I think yours is the more o
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If humans were created by Jesus out of the scorched remains of Titans on the back of a giant turtle, evolution would not be any less observable.
If the moon is held above the earth by the magical crystals of Atlantis, which draw their energies from the immortal spirit of Vlad the Impaler, then gravity would not be any less observable.
So what? (Score:2, Insightful)
Evolution? (Score:2, Funny)
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yes, and if you run an I-don't-have-to-outrun-the-bear-just-you experiment on a species for a couple generations, they will eventually evolve some mechanism for going faster and faster. Which is what "happened" here... except, partway into the beginning of the experiment, they realized that they didn't have to do any real outrunning, they just needed to climb a tree. So, naturally, the ones that were better at climbing trees survived and had more chilluns... thems chilluns had the same features as their bet
Hmmm (Score:2)
Of course behavior influences evolution... What's evolution, if it's not changing as a reaction to things happening?
Idiotic title (Score:2)
Behavior May Influence Evolution
May??? This has to be the dumbest title ever. Anyone who knows the slightest thing about evolution knows that behavior has a huge influence on how an organism evolves.
Come on Slashdot editors, if you know nothing about a subject then please don't write about it.
Not behavioral evolution..... (Score:2)
Because running up a tree is a poor example.
I'm not a biologist so please correct me if I'm wrong but I thought "behavioral evolution" (which was dominant even after Darwin until about 1900) says that as an animal lives its life, its behavior changes based on the environment and those changes are then passed on to it's children. This would explain how animals were able to adapt and evolve in the then-thought short history of the Earth.
O
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Get Smart! (Score:3, Insightful)
This is a cool experiment, but it's nothing "new" -- there's no new knowledge here. At all.
AND there's NOTHING AT ALL about "behavior may be inherited!" Where did THAT come from -- anyone?(*) All these lizards were already prone to running up trees. The ones with shorter legs did it better, and within just a few generations the average legs length of the population was shorter.
That's *basic* evolution, people. Go read a damn book!!! The submitter of this article makes me angry because I realize now the fight for education about Evolution isn't just for stupid fundamentalists. A lot of smart people don't get it either.
I highly recommend getting yourself a copy of "The Selfish Gene" by Richard Dawkins. Read all the chapter notes, too -- get the recent version, don't gt an original copy because it makes you cool. Dawkins commentary on what he wrote in the newer printings is invaluable. It's an excellent book, and it's FUN to read... seriously!
(* I mean, in this context. It's well-known that behavior is inherited -- but not learned behavior.)
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Mary Jane West-Eberhard's Developmental Plasticity and Evolution [amazon.com]
Jablonka & Lamb's Evolution in Four Dimensions: Genetic, Epigenetic, Behavioral, and Symbolic Variation in the History of Life [amazon.com]
Both books show quite well how the modern synthesis is changing and what is likely to incorporated into it. The former book is particularly revolutionizing, the latter is every bit as readable as Dawkins is for the layperson. Both books benefit from the wealth of insigh
seen something similar in possums. (Score:3, Insightful)
Apparently the stress put on possums on the mainland is high enough to cause genetic changes. the stress weakens the immune system and has other side effects that produced a less healthy and capable possum. One possibility that was raised is that on the mainland a good number of possum are killed by vehicles. Cars are obviously a predator that mainland possum can adapt to, or maybe there hasn't been enough time yet?
I wish I could find the exact story but all I end up with are references to NZ based studies.
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Definitely bears further study (Score:2)
Pure random chance in conjunction with natural selection seems inadequate, by itself, to explain many of the, sometimes rapid, evolutionary changes that we see in nature. Some kind of feedback system whereby the useful traits of one generation are emphasised in succeeding generations (to a greater degree than pure genetic inheritance would suggest) could be the key miss
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Depending on how dire the environmental change is that made previous accumul
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Yes, as I tried (inadequately) to explain, I am quite aware of the theory o
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Note that when it comes to things like
Behavior? (Score:2)
The biggest influence on evolution is the environment (competetors, predators, food sources, climeate, etc). What seems to happen is that genetic variation slowly (by it's nature) builds in a population over time, then the environment occasionally quickly changes (the environment can change quicker than genetics can) thus suddenly making some previously begign genetic changes beneficial and others detrimental. I believe this is the basis for the "theory" (i.e. o
Novell's Behavior (Score:2)
Apparently stupid scientist effect is higher (Score:2)
By adding a predator to an island where a species of lizards lived with no predators
And who do you think you are, gods, to play with local evolutionary process of a isolated place ? Which idiot local government official gave you the permission to toy with the island ?
But most important of all, HOW can you muster the guts to come up in front of scientific community after breaking something irreperably while trying to observe it ?
Could be an epigenetic effect in action. (Score:2)
(Source
there is nothing controversial in that topic... (Score:2)
Well, Duh! (Score:2)
How are longer legs "behaviour"? Not that I would be surprised that behaviour has Darwinian consequences. The behaviour of reproductive mating has considerable consequences - species that stop reproducing lose the evolutionary challenge.
About as dumb an article as you get
Beliefs? (Score:2)
Wow, seriously? The Slashdot crowd is usually educated enough for that statement not to be necessary.
If you read Slashdot regularly, and you don't believe in Evolution, you must have an incredible ability to compartmentalize your life.
Finally!!! (Score:2)
Evolution? Maybe not (Score:3, Insightful)
This could simply be the animals with long legs being eaten at a more frequent rate, so the short legged lizards are the ones surviving and reproducing. This is, at best, micro-evolution. Their genetic makeup isn't changing to accomidate the need for short legs (like evolution would *know* that it needed short legs). Its selective breeding.
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So, if you are presenting the history of biological theory, that theory should come up...
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When the anoles learned that they could better avoid the predator lizards by climbing trees, the shorter-legged lizards had a climbing advantage, and they were being selected for.
The summary only tells half of the story. The article spells it out completely. It was a behavior change on the part of the prey that caused a change in which trait
Alternatively... (Score:2)
On introduction of the predators some lizards climbed to escape and some ran. For a while the longest legged run-away lizards survived as the predators ate the slower ones first. Why chase after the quickest ones when you can eat all the slow ones first.
As the slower ones were all eaten then the longer legged ones were caught as well and eaten. Now if the predators were slightly slower or the longer legged run-aw
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