Parasaurolophus cyrtocristatus skeleton on display at the Field Museum of Natural History, in Chicago. Life-size Parasaurolophus Skeleton Sculpture for Sale This dinosaur was named “The Good Mother” because there is evidence that she looked after her nest of eggs very well. And her fossil was found among a whole area of nests, all clustered together, like a mass incubation ground. She was excavated in Montana during 1979. a b Earls, Kathleen D. (Feb 2000). "Kinematics and mechanics of ground take-off in the starling Sturnis vulgaris and the quail Coturnix coturnix" (PDF). The Journal of Experimental Biology. 203 (Pt 4): 725–739. doi: 10.1242/jeb.203.4.725. PMID 10648214.

The legs are attached to a very strong, lightweight assembly consisting of the pelvic girdle extensively fused with the uniform spinal bone called the synsacrum, [7] [10] which is specific to birds. The synsacrum is built from the lumbar fused with the sacral, some of the first sections of the caudal, and sometimes the last one or two sections of the thoracic vertebrae, depending on species (birds have altogether between 10 and 22 vertebrae). [9] Except for those of ostriches and rheas, pubic bones do not connect to each other, easing egg-laying. [8] Rigidity and reduction of mass [ edit ] P. Godefroit et al., “ A Jurassic ornithischian dinosaur from Siberia with both feathers and scales,” Science 345, 6195 (25 July 2014). Body size Corythosaurus is an extinct genus of hadrosaur dinosaurs that lived in the Late Cretaceous period. Its name means “Helmet lizard”. It is also known by the incorrectly spelled name, Carninthosaurus in The Lost World: Jurassic Park script and media. Skeleton plays an important role in the living of vertebrate species, including providing structural support, protecting internal organs, acting as a major source of inorganic ions, and withstanding muscular contraction ( Sommerfeldtand Rubin,2001; Wagnerand Aspenberg,2011; Florencio-Silvaetal., 2015). In the skeletal system that contains hundreds of bones, sternum, a part of the thoracic cage, is one of the heavily studied single bones.Maxwell E.E., Larsson H.C. Comparative ossification sequence and skeletal development of the postcranium of palaeognathous birds (Aves: Palaeognathae) Zool. J. Linn. Soc. 2009; 157:169–196. [ Google Scholar] Here is a simple diagram of a bird skeleton (from Wikimedia Commons). Many of the bones are clearly homologous to those in mammals, but there are a few important differences.

Brekken R.A., Sage E.H. SPARC, a matricellular protein: at the crossroads of cell–matrix. Matrix Biol. 2000; 19:569–580. [ PubMed] [ Google Scholar]Feathers are one of the defining characteristics of birds, and they play a key role in flight. However, recent paleontological studies show that feathers evolved before flight. What did these feathers do in the non-flying ancestors of birds? The words in bold type are things that you might be asked to identify on the lab exam. Rather than focusing only on the names of the bones, it's useful to think about the major differences between bird skeletons and mammal skeletons, as described below. The pectoral girdle is the set of bones that supports the forelimbs (wings). In birds, it includes the furcula, scapula and coracoid:

Now look at the dinosaurs. Allosaurus, Tyrannosaurus, and Velociraptor are are clearly dinosaurs; after all, dinosaurs like these were featured in the Jurassic Park movies. Notice that there is no clade that includes all these dinosaurs but does not include birds. If Dinosauria is a valid taxonomic group (and it is), then it has to include birds. As it turns out, not all the dinosaurs became extinct; birds are the last surviving dinosaurs. Most people tend to think that the age of dinosaurs ended long ago; however, given that there are over 10,000 species of birds on Earth (compared to 5500 species of mammals), one could say that we are still living in the age of dinosaurs. Judging by the petite size (and a bit of hopeful bias) I initially thought they could be mallard (Anas platyrhynchos). Serving probably as the primary take-off accelerator. In the common vampire bat, by contrast, the required force is generated by the wing. [18] [19]Vega-Jorquera L., O'Connor J., Vargas A.O. Ossification of the sternum in a flighted paleognath and the evolution of the keel in modern and extinct carinatae. J. Morphol. 2019; 280 S233-S233. [ Google Scholar] Look at the date on the tag around this owl's leg— this specimen has been in our lab for a long time. Bat wing vs. bird wing Zheng X., Wang X., O'connor J., Zhou Z. Insight into the early evolution of the avian sternum from juvenile enantiornithines. Nat. Commun. 2012; 3:1116. [ PubMed] [ Google Scholar] Florencio-Silva R., Sasso G.R.D.S., Sasso-Cerri E., Simões M.J., Cerri P.S. Biology of bone tissue: structure, function, and factors that influence bone cells. Biomed. Res. Int. 2015; 2015:421746. [ PMC free article] [ PubMed] [ Google Scholar] Explore the science concepts that underpin knowledge and understanding about birds and their structure, function and adaptations. Activity ideas

Because avian forelimbs are wings, many forelimb functions are performed by the bill and hindlimbs. [10] It has been proposed that the hindlimbs are important in flight as accelerators when taking-off. [18] [19] Some leg and foot functions, including conventional ones and those specific to birds, are: Totipalmate: all four digits (1–4) are joined by webbing. Found in gannets and boobies, pelicans, cormorants, anhingas and frigatebirds. Some gannets have brightly colored feet used in display. [3] [21] How Dinosaurs Shrank and Became Birds. Singer, 2015. Quanta. Excellent exploration of the evolutionary processes behind this amazing transition. The foot's upper bones ( proximals) are fused with the tibia to form the tibiotarsus, while the centralia are absent. [5] [6] The anterior (frontal) side of the dorsal end of the tibiotarsus (at the knee) contains a protruding enlargement called the cnemial crest. [2] Patella [ edit ]The most common arrangement is the anisodactyl foot, and second among perching birds is the zygodactyl arrangement. [3] [7] [21] Claws [ edit ] A comparison of bird wings and bat wings is an example of both homology and analogy. These wings, along with the arms of humans or the forelegs of cats, are examples of vertebrate forelimbs. It's clear that all these are homologous structures. The last common ancestor of birds and mammals had forelimbs with similar bones. In each of these species, the forelimbs develop the same way in the embryo, using homologous genes to control limb development. So as forelimbs, the wings of bats and birds are homologous. On the other hand, as wings they are analogous. The most recent common ancestor of bats and birds had forelimbs, but not wings. Wings evolved separately in bats and birds, so the wings of bats should be considered analogous to the wings of birds. Bats also have keeled sternums Feathers. Birds are the only living animals with feathers, and feathers are essential for the mechanics of bird flight. However, many nonflying dinosaurs also had feathers.