Question

In building a phylogenetic tree, biologists look for traits derived from a common ancestor. To use this form of analysis with the utmost fidelity, scientists must differentiate homologous traits from the convergent ones. Which of the following would be considered a homologous trait?
A. The wings of birds and bats
B. The ability of birds and dolphins to echolocate
C. The streamlined body form of fish and dolphins
D. The flippers of dolphins and the wings of bats

Answer 1

Hint:The similarity that is shared due to ancestry between the pair of structures and genes in different taxa are called the Homology. Homologous structures that are adapted to different purposes as a result of descent modification from a common ancestor is explained by evolutionary biology. The most common examples of the homologous structures are front flippers of the whale, bats, and bird's wings, and four-legged vertebrates (crocodiles, dogs) are derived from the ancestral tetrapod structure.

Complete answer:The opposite of homologous organs is analogous organs which do similar jobs in two taxa that were not present in their most recent common ancestor but rather evolved separately. For example, the wings of insects and birds are evolved independently in most of the widely spread groups that are converged functionally and are analogous. In the same way, the wings of the bird and sycamore maple seed are analogous.
The forelimbs of all wings are evolved from the same ancestors so that they are called Homologous. For example, the flipper of a turtle or a dolphin, the arm of a human, the foreleg of a horse, and the wings of both bats and birds are ultimately homologous.
Hence, the correct option is (D) The flippers of dolphins and the wings of bats.

Note: Similar features that have been raised through the convergent evolution functionally are said to be analogous whereas homologous traits have dissimilar functions with the same origin. Forelimbs of bat, bird, and pterosaur wings are homologous but their wings are analogous and share the same ancestral features.