GENETICS AND EVOLUTION
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the wings of a butterfly
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the hip bones found in some species of snake
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the thick fur and layer of fat of some mammals in cold climates
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the sharp spines of a cactus
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Detailed explanation-1: -Pythons and boa constrictors have tiny hind leg bones buried in muscles toward their tail ends. Such features, either useless or poorly suited to performing specific tasks, are described as vestigial. They are also intriguing evidence of the evolutionary histories of species.
Detailed explanation-2: -No, snakes do not have hip bones. Some snakes retain small spurs of bone where their ancestors once had hips and some even have tiny bones of vestigial legs embedded in their muscles, but they do not have the pronounced or functional hip bones now that snakes no longer have legs.
Detailed explanation-3: -Structures that have no apparent function and appear to be residual parts from a past ancestor are called vestigial structures. Examples of vestigial structures include the human appendix, the pelvic bone of a snake, and the wings of flightless birds.
Detailed explanation-4: -A vestigial structure is a biological structure that has lost a major ancestral function and is usually drastically reduced in size. Well-known examples include the eyes of blind cave fishes and blind cave salamanders, and the diminutive wings of kiwis and emus.