EVOLUTION
EVIDENCE FOR EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Snakes have adaptations for walking if the environment changes.
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Snakes share a common ancestor with animals that use legs for walking.
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Snakes share a common ancestor with organisms that have no leg bones.
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Snakes have the same DNA as organisms that have no leg bones.
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Detailed explanation-1: -Vestigial legs are a clue that snakes descended from lizards. Over 100 million years ago, some lizards happened to be born with smaller legs, which, in certain environments, helped them move about unencumbered. As generation after generation survived and reproduced, this new form flourished.
Detailed explanation-2: -The evolution of a long, legless body could be beneficial to life underwater as it would enable eel-like swimming. But it could also be beneficial on land, making burrowing and hunting underground easier.
Detailed explanation-3: -The findings appear today (Oct. 20) in the journal Current Biology. Taken together, the mutations in the enhancer of a gene known as Sonic hedgehog disrupt a genetic circuit that drives limb growth in snakes.
Detailed explanation-4: -Vestigial structures For instance, the tiny vestigial leg bones found in some snakes reflect that snakes had a four-legged ancestor. The small leg-like structures of some snakes species, like the Boa constrictor, are vestigial structures.