Their skeletal structure is homologous, due to common descent from the forelimb of a reptilian ancestor but the modifications for flying are different and independently evolved, and in this respect they are analogous.įeatures that become more rather than less similar through independent evolution are said to be convergent. The similarities between the wings of bats and birds are partially homologous and partially analogous. Their wings are not modified versions of a structure present in a common ancestor but rather have developed independently as adaptations to a common function, flying. The wings of birds and of flies are analogous. Correspondence of features due to similarity of function but not related to common descent is termed analogy. The skeletons of these limbs are all constructed of bones arranged according to the same pattern because they derive from a common ancestor with similarly arranged forelimbs. The forelimbs of humans, whales, dogs, and bats are homologous. As discussed above in the section The evidence for evolution: Structural similarities, correspondence of features in different organisms that is due to inheritance from a common ancestor is called homology. SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!Ī distinction has to be made between resemblances due to propinquity of descent and those due only to similarity of function.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.COVID-19 Portal While this global health crisis continues to evolve, it can be useful to look to past pandemics to better understand how to respond today.Student Portal Britannica is the ultimate student resource for key school subjects like history, government, literature, and more.This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find.Demystified Videos In Demystified, Britannica has all the answers to your burning questions.Britannica Classics Check out these retro videos from Encyclopedia Britannica’s archives.Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions.
0 Comments
Leave a Reply. |