If a bat, a human, an alligator, and a penguin all evolved from a common ancestor, then they should share common anatomical traits. In fact, they do. Compare the forelimbs of the human, the bat, the penguin, and the alligator. Find the humerus, radius, ulna, and carpals in each forelimb. Though the limbs look strikingly different on the outside and though they vary in function, they are very similar in skeletal structure. More significantly, they are derived from the same structures in the embryo. Structures that are embryologically similar, but have different functions, are called homologous structures. Though these animals look different, a comparison of homologous structures indicates that they are quite similar. This suggests that these animals evolved from a common ancestor.
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Homologous structures
Homologous Structures - California LIFE Science Prentice Hall (7th grade)
Homologous structures.
A structure with similar shape but a different use
The presence of homologous structures (for example, the bone structure in chimpanzee arms, human arms, and whale flippers) indicates that the species sharing that homologous structure share a common ancestor.
Homologous structures.
I learned about homologous and heterozygous structures in Biology.
Homologous structures (Not to be confused with Homologous pairs)
what is Similar structures that related species have inherited from a common ancestor
Homologous structures are structures that indicate a related evolutionary ancestry, not just similarity. For example, the flipper of a whale, the wing of a bird, and the arm of a a human are similar in their bone structure. Analogous structures are structures that are similar in appearance and function but are not the result of shared ancestry. For example, the wings of a birds and insects have the same function, but they do not reflect a shared ancestry.
They are different because homologous structures have the same structure, but serve a different function. Like mammal arms(human, bat and whales). Analogous structues are different structures, but serve the same function. For example, bat wings and butterfly wings.
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