GENETICS AND EVOLUTION
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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similar physical features in organisms that share a common ancestor, but the features serve completely different functions
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features of different species that are similar in function but not necessarily in structure and which do not derive from a common ancestral feature
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a biological structure that has lost a major ancestral function and is usually drastically reduced in size
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None of the above
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Detailed explanation-1: -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-2: -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.
Detailed explanation-3: -Often, these vestigial structures were organs that performed some important functions in the organism at one point in the past. However, as the population changed due to natural selection, those structures became less and less necessary until they were rendered pretty much useless.
Detailed explanation-4: -Vestigial structures are body parts that have lost their use through evolution. Homologous structures are structures that have a common function and suggest common ancestry. Similar embryos suggest that these animals are related and have common ancestors.