jackson@utzoo.UUCP (Don Jackson) (12/20/86)
>>Turkeys belongs to a class of dinosaur??? (P.M Koloc)
Sorry to break the news, but birds and dinosaurs *are* more closely related
than dinosaurs and present-day reptiles.
--
Name: Don Jackson
Mail: Dept. Zoology, Univ. Toronto
Toronto, Ontario, Canada M5S 1A1
UUCP: {allegra,ihnp4,linus,decvax}!utzoo!jacksonjc@cdx39.UUCP (John Chambers) (12/23/86)
> >>Turkeys belongs to a class of dinosaur??? (P.M Koloc) > > Sorry to break the news, but birds and dinosaurs *are* more closely related > than dinosaurs and present-day reptiles. > Hmmm...I thought that birds had been classified as a suborder of the dinosaurs, not a class. Anyone out there know what the official taxonomy really is these days? Like, draw me a cladogram, perhaps, and label the 'class' and 'order' levels. It is interesting to hit people with the 'fact' that dinosaurs didn't die out; that they probably ate one for Thanksgiving. I wonder when the media will hear the news. -- John M Chambers Phone: 617/364-2000x7304 Email: ...{adelie,bu-cs,harvax,inmet,mcsbos,mit-eddie,mot[bos]}!cdx39!{jc,news,root,usenet,uucp} Smail: Codex Corporation; Mailstop C1-30; 20 Cabot Blvd; Mansfield MA 02048-1193 Clever-Saying: For job offers, call (617)484-6393 evenings and weekends.
evs@duke.UUCP (Ed Simpson) (12/31/86)
In article <531@cdx39.UUCP> jc@cdx39.UUCP (John Chambers) writes: >Hmmm...I thought that birds had been classified as a suborder of >the dinosaurs, not a class. Anyone out there know what the official >taxonomy really is these days? Like, draw me a cladogram, perhaps, >and label the 'class' and 'order' levels. In the most commonly accepted classificatory schemes Dinosuars belong to the class Reptilia and birds comprise their own class, Aves. The phylogeny is as follows: Phylum Chordata -> Subphylum Vertebrata -> Class Aves. Birds arose from the group of dinosuars called saurischians (meaning "lizard- hipped", which is kind of strange since the other major group of dinosaurs were ornithiscians, meaning "bird-hipped"). Birds are so different from living reptiles that it warrants placing them in a class separate from reptiles. I think the dispute is whether dinosaurs should be placed in the class Reptilia. Both birds and mammals have a four chambered heart and are endothermic (traits arrived at independently) and there is some evidence that dinosaurs were also endothermic. Does anybody know anything about the structure of the dinosaur heart? Dinosaurs may have been sufficiently different from living reptiles to justify placing them in their own class, perhaps including birds in this separate dinosaur class. However their are some people who think birds should be placed in the class Reptilia as surviving dinosaurs. A common phylogenetic tree for reptiles and their descendents is as follows: Turtles Tuatara Lizards Snakes Crocs Birds Mammals | | | | | | | | | |__________| | | | | | | ______________| | | | | | | | | | | | | | | Plesiosaurs | | | | Pterosaurs | | | | | | | | | | | | | | | | | | | | | | | | Ornithiscian Saurischian | | | | | \ | Dinosaurs Dinosaurs | | | | \ \ | | / | | | -------\ \ \ | / | | | \ \ \ | / Ichthyosaurs | | | \ \ \ | / / | | |______________ \ \ \____ | / / | | \ \ \ | | | / | | \ \ ------Thecodonts / | |______________________ \ \ / / | \ \ \ / / Therapsids \ \ \ ____/ / / \ \ | | / / \ | | | __________/ / | | | | | / Stem Reptiles-------------------------/ ------------------------------------------------------------------------------- {decvax, seismo}!mcnc!duke!evs Ed Simpson, P.O.Box 3140, Duke Univ. Medical Center, Durham, NC 27710 -- {decvax, seismo}!mcnc!duke!evs Ed Simpson, P.O.Box 3140, Duke Univ. Medical Center, Durham, NC 27710
michaelm@bcsaic.UUCP (Michael Maxwell) (01/05/87)
In article <531@cdx39.UUCP> jc@cdx39.UUCP (John Chambers) writes: >> >>Turkeys belongs to a class of dinosaur??? (P.M Koloc) >> >> Sorry to break the news, but birds and dinosaurs *are* more closely related >> than dinosaurs and present-day reptiles. >> >Hmmm...I thought that birds had been classified as a suborder of >the dinosaurs, not a class. I saw an exhibit yesterday (at the Science Center in Seattle) that said a Pterydoctyl fossil had been found with traces of fur. No reference. Does anyone know anything about this? -- Mike Maxwell Boeing Advanced Technology Center arpa: michaelm@boeing.com uucp: uw-beaver!uw-june!bcsaic!michaelm