REVIEW OF THE EVIDENCE THAT WE HAVE THAT DINOSAURS WERE WARM-BLOODED ANIMALS

Dinosaurs were vertebrates animals, which means that they were animal with backbone. Even today whether dinosaurs were cold-blooded or warm-blooded animals remains unclear. This is because fossil evidence which have been studied by paleoanthropologists prior 1970s indicates that dinosaurs were cold-blooded animals (Wikipedia contributors, 2006). Therefore post 1970s paleoanthropologists have started to find evidence from the fossil remains which indicates that dinosaurs were warm-blooded animals. Being warm-blooded animals mean that dinosaurs were able to control their body temperatures.

Paleoanthropologists did provide evidence which support that dinosaurs were warm-blooded animals. The evidence which were provided by the paleoanthropologists to support their agreement include ''big ribcage, straight legs, rate of evolution, bone structure and the rate of growth'' (Bakker, 1972). All of the above mentioned characteristics support the evidence by the scientists that dinosaurs were warm-blooded animals because of the similar characteristics which are both have in common with birds. The characteristics of the fossil remains of both dinosaurs and birds were compared.

In 1993 the evidence from the fossil remains which have been found in South Dakota, USA prompted paleoanthropologists to believe that dinosaurs were warm-blooded animals. The above statement made by the paleoanthropologists is supported by the fact that dinosaurs were active organisms which were moving at the highest speed. This is because warm-blooded animals are able to control their own body temperature, they donot rely in the external environment. Some paleoanthropologists on the other side disputed the fact that dinosaurs were warm-blooded animals, because in the location where many fossils have been found it was extremely hot. The hot temperature was supposed to kill the dinosaurs.

Bakker (1972) says that in April 2000 a team of paleoanthropologists from the University of North Carolina State led by Michael Hammer said that they have discovered the first fossil of dinosaurs. The fossil was thought to be the fossilized heart. The fossilized heart was named Willo. It was the fossilzed heart which suggests that the fossilized heart resembles that which are found in the warm-blooded animals or bird not reptile. The weight of the fossilized heart was 666 pounds and it was dated to 6mya.

Other group of paleoanthropologists also supported the fact that dinosaurs were warm-blooded animals. Their arguments were based on the study conducted by studying the isotopes in the bones of the dinosaurs. Evidence from the isotopes studied from the bones also suggested that warm-blooded animals grow quickly as compared to the cold-blooded animals which grow slowly. Even though the evidence provided by studying the ''isotopes seemed to be clear that dinosaurs were warm-blooded animals'', but some paleoanthropologists disputes this fact (Bakker, 1972).

In conclusion, one can say that the fact that dinosaurs were either warm-blooded or cold-blooded animals remains unclear. This is because evidence from the study of the fossil remains are still even today providing us with the new evidence of whether dinosaurs are either warm-blooded or cold-blooded animals. The finding of the new evidence come-up with the new information about the reality of this extinct species, dinosaurs. In other words new evidence means new speculation about whether dinosaurs were warm-blooded or cold-blooded animals.

References:

Bakker, R. 1972. Were Dinnosaurs warm-blooded?. [Online]. Available from:
http://www.dinoruss.com/de_4/5c51d90.htm [12 February 1972, 13: 33]

Wikipedia contributors. Warm-blooded [Internet]. Wikipedia, The Free Encyclopaedia; 2006 May 09, 17:28 UTC [cited 10 May 2006, 14:19]. Available from: http://en.wikipedia.org/wiki/Warm_blooded

Williston, S. W. 2005. Are birds derived from dinosaurs? Kansas City Review of Science and Industry 3:224-226. [Online]. Available from: http://www.txtwriter.com/conscience/Articles/dinoblood.html

Peter Muvhali
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