Monday, May 15, 2006

BIRDS ARE THE LIVING RELATIVE OF DINASAURS

Birds have some characteristics which are similar to Dinosaurs. A Tyrannosaurs rex dinosaur that died sixty eight million years ago provided some of the strongest evidence yet that birds are the closest living relatives of dinosaurs. Dinosaurs had bone similar to female bird. Both Dinosaurs and bird shared common ancestor. Embryo of Dinosaurs was found without teeth.

The researchers said that a Tyrannosaurus rex dinosaur had soft thighbone tissues which strongly suggest that it was a female, and nearly to lay eggs. The bone tissue was strongly similar to that made inside the bones of female birds. Mary Higby Schweitzer of North Carolina State University in Raleigh indicated that no other living type of animal, when they are producing the hard shells of eggs just before they lay them. The emphasis to demonstrating gender, it also links the reproductive physiology of dinosaurs to birds very closely. It indicates that dinosaurs produced and shelled their eggs much more like modern birds than like modern crocodiles.

Mudge said that Dinosaurs were the ancestor of the birds or stock from which the latter have been derived by evolution. The bones of the hinds feet of a few species closely to look like those of birds, some of the bones were hollow that indicate that other resembles will be found and that bird was the outgrowth of reptiles. Dinosaurs had three toes like the bird, some of European and nearly of the entire American, have four and five toes and structure. When four toes were seen in the dinosaurs, the fourth never rotate backward like that of the birds. Dinosaurs had the tibia and fibula which are separated always whereas the birds have these bones joined. The termination of the caudal vertebrata of the dinosaur was always small and did not tend toward the plowshare structure of birds.

Sinosauropteryx was the first dinosaur with non flying to have proto feathers and it was the earliest bird-like dinosaur. This clearly indicate that feathers arose before arose before flight. This also shows the common ancestor of bird and dinosaurs. The fossil had features that the birds have for instance plumage

Paleontologists have discovered two new bird-like dinosaurs with simple feathers and many other bird-like features. These finds strengthen the theory that birds evolved from dinosaurs. Although these new species had some form of primitive feather, these feathers were symmetrical in cross-section which made then useless for flight. The dinosaurs' arm-length was also insufficient for flight. The feathers were most likely used as insulation, keeping in body heat. These new dinosaurs Protarchaeopteryx robusta, and Caudipteryx zoui, together with the recently found Sinosauropteryx prima, have characteristics common to both theropod "(beast-footed") dinosaurs and to birds. All three, plus many specimen of a very primitive bird (Confuciusornis Sanctus) were found in the period from 1996 to 1997 in an ancient lake bed in Liaoning Province, in China.

The carnivore dinosaurs had a complex system of air sacs similar to the setup of birds of nowadays. According to the research led by Patrick O'Connor of Ohio University, the lungs of carnivores that are bipedal with the feet similar like bird are likely pumped air into hollow sacs in their skeleton. Comparisons between bird and dinosaur skeletons, as well as cladistic analysis, strengthen the case for the link, mostly for a branch of theropods called maniraptors. Skeletal similarities include the neck, pubis, wrists (semi-lunate carpal), arm and pectoral girdle, shoulder blade, clavicle and breast bone.

A dinosaur embryo was found without teeth, which suggest some parental was used to feed young dinosaur, possibly the adult dinosaur go over nutrition into the mouth of young dinosaur. This type of behaviour was seen in many modern bird species. The skeletal similarities include the neck, pubis, wrists, arm and pectoral girdle, shoulder blade clavicle and breast bone. A number of feathered dinosaurs provided clear evidence of the close relationship between dinosaurs and birds.

References

Chang G (1999). Dinosaurs were hybrid of cold-blooded, warm-blooded animals [internet] 2006 May 09, 11:30 UTC [cited 2006 May 10] Available from: http://www.exn.ca.Html/Templates/topicpage.cfm?ID=19990122-51&Topic=Dinosaur
Wikipedia Contributors. Dinosaurs are warm or cold blooded, The free Encyclopaedia [internet] 2006 May 06, 08:30 UTC [cited 2006 May 08] Available from: http://wikipedia.org.wiki.dinosaur
MasiyaKedibone
CSIR PTA
0001
Cell No:0732519071
Tel No:0128412123
Fax:0128423676
E-mail:kmasiya@csir.co.za
Web log: http://kedibone-kedimasiya.blogspot.com/

0 Comments:

Post a Comment

<< Home