are wings of bats and birds homologous

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This action is not available. 20. 2: Ascertaining Evolutionary Connections 20: Phylogenies and the Evolutionary Past”}”20 2A:__Distinguishing_between_Similar_Traits” : “property get [Map MindTouch. Deki. Logic. ExtensionProcessorQueryProvider+<>c__DisplayClass230_0. b__1]()”, “20. 2B:_Building_Phylogenetic_Trees” : “property get [Map MindTouch. Deki. Logic. ExtensionProcessorQueryProvider+<>c__DisplayClass230_0. b__1]()” }{ “20. 01:_Organizing_Life_on_Earth” : “property get [Map MindTouch. Deki. Logic. ExtensionProcessorQueryProvider+<>c__DisplayClass230_0. b__1]()”, “20. 02:_Determining_Evolutionary_Relationships” : “property get [Map MindTouch. Deki. Logic. ExtensionProcessorQueryProvider+<>c__DisplayClass230_0. b__1]()”, “20. 03:_Perspectives_on_the_Phylogenetic_Tree” : “property get [Map MindTouch. Deki. Logic. ExtensionProcessorQueryProvider+<>c__DisplayClass230_0. b__1]()” }Tue, 31 Oct 2023 22:18:05 GMT20. 2A: Distinguishing between Similar Traits1353113531Joshua Halpern{ }AnonymousAnonymous2falsefalsehttps://bio. libretexts. org/@app/auth/3/login?returnto=https%3A%2F%2Fbio. libretexts. org%2FBookshelves%2FIntroductory_and_General_Biology%2FBook%253A_General_Biology_(Boundless)%2F20%253A_Phylogenies_and_the_History_of_Life%2F20. 02%253A_Determining_Evolutionary_Relationships%2F20. 2A%253A__Distinguishing_between_Similar_Traits .

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  • Explain the difference between homologous and analogous structures

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In this homology and analogy discussion, bat and bird wings are cited as examples of similarly shaped organs:

You are correct, though, that the wings of bats, birds, and pterosaurs are somewhat similar to one another due to their shared evolutionary ancestor, which is the tetrapods’ front limbs.

Perhaps one could argue that the wings of pterosaurs, birds, and bats are analogous organs to front limbs but homologous organs to wings.

This page has pictures of the skeletal structure of each:

They have comparable front limbs, as you can see, consisting of the same set of bones and muscles. However, the arrangement of those bones to form wings varies: bats have three lengthened fingers encircled by a flap of skin; birds have small, fused finger bones with the surface of the wing composed of feathers; and pterosaurs have a lengthened pinky finger maintaining a flap of skin that forms the wing.

Furthermore, it is true that the front limbs of birds, pterosaurs, and bats all share a common evolutionary ancestor in tetrapods, but their pathways to becoming wings are distinct and independent histories. In other words, the pterosaurs, birds, and bats shared a common ancestor that possessed front limbs, but those limbs weren’t wings.

In contrast, the “wings” of flying fish share a common ancestor with those of birds, bats, and pterosaurs, having developed from the pectoral fins of their common bony fish ancestor. They obviously developed wings on their own, and their evolutionary history as “limbs” is significantly different. However, there is absolutely no similarity in origin between the wings of insects and those of vertebrates. Insects and vertebrates shared a common ancestor who lacked any appendages whatsoever, including bones and an exoskeleton. Both lineages independently evolved limbs and hard support structures, then modified some of their existing anatomical features to facilitate flight.

It’s interesting to note that a book called On the Wing: Insects, Pterosaurs, Birds, Bats, and the Evolution of Animal Flight by David E. recently came out about the flight of bats, birds, pterosaurs, and insects. Alexander. Anyone with an interest in the topic might find it to be a worthwhile read. Here are some reviews of the book:

ETA: Have a look at these two sidebar questions to help you moderate your thinking on the homologous vs. analogous organs (or homology versus homoplasy) debate.

Which ask similar questions you did, but of the fins of whales vs the fins of sharks. And thats a funny one isnt it! Because where in the pterodactyl example we have a common ancestor who had front limbs but didnt have wings, in that case the common ancestor of whales and sharks did have pectoral (“chest-level”) fins, that the fins of whales and sharks descend from! So, homologous? But the fins of whales spent so much of their evolutionary history not being fins at all that it does make one want to say the homology is at the “front limb thingy” level not the “fin” level. I mean, as far as evolutionary distance goes, the wings of flying fish and of bats are actually more closely related to each other than the fins of whales and of sharks are!!! (the evolutionary history there goes: jawed fish (Eugnathostomata) -> cartilaginous fish (Chondrichthyes; led to sharks) and bony fish (Osteichthyes; led to flying fish, bats and whales).

99% of the 20%22 shark-fin-like 20%22 appearance of whale fins developed long, long after their split from the shark lineage. I’m not sure what the 20%20 front fins of the 20%20 jawed fish 20%20 common ancestor 20%20 looked like, but it’s possible it looked different from the 20%20 whale/shark fins 20%20 too, so some of the 20%22 shark-fin-like 20%22 appearance of shark fins could have developed independently after the split.

FAQ

Are the wings of bats and birds homologous or convergent?

1: Homologous structures: Bat and bird wings are homologous structures, indicating that bats and birds share a common evolutionary past. Notice it is not simply a single bone, but rather a grouping of several bones arranged in a similar way.

What are the wings of a bat and bird?

Bat wings consist of flaps of skin stretched between the bones of the fingers and arm. Bird wings consist of feathers extending all along the arm. These structural dissimilarities suggest that bird wings and bat wings were not inherited from a common ancestor with wings.

What is the wing of a bat homologous to?

The wing of a bat is homologous to the flipper of a whale. Both of these organisms are mammals. The bat uses its modified wing to fly, whereas the whale uses its modified flipper to swim. When looking at skeletal structure and phylogenetic evolution, however, these structures are more similar than they are different.

What do bats and birds have in common?

Bats and birds pretty much have only one main thing in common, flight, and some birds don’t even fly! And when it comes to flying, bats are adapted to be more maneuverable and agile flyers than most birds. Despite sharing wings, bats and birds are different in almost every way.