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Behavior May Influence Evolution
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."
The study also supports a somewhat controversial idea in biology: Animals' behavior in response to environmental change can spur evolutionary adaptations.
Could that imply that the behaviour of disbelieving scientific facts could spur a reduction in brain size in order to adapt to reduced intelligence?
"We are all geniuses when we dream"
- E.M. Cioran
When the environment changes, some animals are better adapted to the new change than others. Details at 11.
'Sensible' is a curse word.
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. There is nothing new or "adapted." Also, if the short-legged ones get away and the long-legged ones don't, isn't that going to inherently affect how many have long legs and how many have short, by proportion?
I've read good arguments that many of these are actually adaptations that will help the species survive.
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?
'Sensible' is a curse word.
From the article description, I thought this experiment was going to provide evidence for Lamarkism or something. In fact, this seems an interesting, but not too-surprising finding.
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.
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 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.
My work here is dung.
Right wingers can't be religious people. They can only assert they are (and they probably know it since they kill religion the same way fascism kills nationalism) but reading the ABC of most religions proves the opposite.
:D
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.
---- MISSING MISCELLANEOUS DATA SEGMENT --- [sigdash] trolololol
I'm hijacking a higher thread since pretty much everything written below is just plain wrong.
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 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 the article has raised from their graves go to rest.
I'm a dreamer, the world is my playpen. But hey, I'm a serious person, I can't dream all the time.
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