# Talk:Hummingbird

Can you please clarify the "no knees" commentary in the morphology section? I don't believe this statement to be correct. All birds have a joint between the femur and the tibiotarsus. In fact, the link provided links to an article on bird feet and legs mentioning this as a common source of confusion, as the joint is often covered by skin or feathers. Please see the link below to a CT reconstruction of Archilochus colubris, where the femoral-tibiotarsal joint is clearly visible. The citations provided for the "no knees" commentary are popular articles and not rigorous enough to support the statement. 
https://digimorph.org/specimens/Archilochus_colubris/ Gbwalth (talk) 18:58, 23 September 2024 (UTC)

Birds do have knees, as shown in this image from the Bird feet and legs page, although the article states that "some species do not have patellas". A good summary source for the leg bones with a description of the hummingbird knee would help - do you have one? Zefr (talk) 19:53, 23 September 2024 (UTC)
Sadly, I'm having trouble finding a specific anatomical description of the femorotibial joint (joint between the femur and tibiotarsus, or knee) in trochilidae. Below are some references to support its existence.
This paper is specifically on hummingbird myology. Though there is no description of the knee itself, several references are made to a knee, as well as some nice illustrations of the pelvic limb.
https://repository.si.edu/bitstream/handle/10088/5185/SCtZ-0385-Lo_res.pdf?sequence=2
This paper has a nice illustration of hummingbird skeletal elements, and the joint between the femur and the tibiotarsus (i.e. the knee) is shown clearly.
https://www.nature.com/articles/s41467-024-48324-y
The Museum of Osteology in Oklahoma City has some really great skeletal mounts, some of which are mentioned in the below article. The article also has a micro-CT scan of the skeleton. Again, the femorotibial joint is shown clearly.
https://svpow.com/category/stinkin-theropods/hummingbird/
This book has some cool pictures of Paleogene trochilid fossils, with mentions of femurs and tibiotarsi - so these fossil birds must also have had knees.
https://link.springer.com/book/10.1007/978-3-540-89628-9
As an aside, this paper has an excellent discussion of hummingbird skeletal anatomy, but sadly does not address the pelvic limbs.
https://www.researchgate.net/publication/270471957_Introduction_to_the_Skeleton_of_Hummingbirds_Aves_Apodiformes_Trochilidae_in_Functional_and_Phylogenetic_Contexts
To state that hummingbirds lack knees implies that they are different from all other birds, and there is no support for this. I respectfully submit that the statement should be taken down. Please let me know if I can assist with anything! Gbwalth (talk) 03:14, 24 September 2024 (UTC)
I also looked widely for an anatomical source specifying whether there is a knee... or not, with no success. This article has anatomical displays, one of a skeletal side view (2nd last figure, prepared by Stanlee Miller of Clemson University) clearly showing a "bent knee" with the femur and tibia at a 90o angle, confirming a hinge joint.
As stated in the article and shown in Fig. 1 of this article, the legs (and knees) do not give a hummingbird much lift on takeoff or other mechanical advantage, except maybe for preening. Zefr (talk) 03:48, 24 September 2024 (UTC)