Authors: Sergio H. Martínez, Marc Rodà, Daniel Salgado (see http://www.uphysicsc.com/2016contest.html)
The largest dinosaurs that walked the earth were approximately an order of magnitude (a factor of ten) more massive than the largest land mammals. It has been hypothesized that this may have been due to factors such as, but not limited to, the different levels of oxygen in the atmosphere, the difference in the effort required for giving birth to live young versus laying eggs, differences in metabolic rates, differences in the availability of food sources, or differences in ambient temperature. Develop a model to account for the differences in mass between the largest dinosaurs and the largest land mammals, and evaluate the effectiveness of this model using biological/paleontological data.
As suggested by recent publications on vertebrate’s maximal size [1], we have worked on a mathematical model based on resources and energy considerations that can be applied in order to account for the differences in mass between dinosaurs and mammals and that permits to reinforce or discard hypothesis about dinosaur’s resources and biological nature. In this paper we analyze the model, apply it with real biological/- paleontological data and use it to give explanations to the maximal body size for land mammals and dinosaurs. Furthermore, other implications of the model are explored in order to give answers to other important questions about dinosaur’s nature. In particular, we have found that dinosaurs having similar characteristics to varanids in terms of energy expenditure when extrapolated to larger mass successfully explains observed mass ratios of one order of magnitude between dinosaurs and mammals.
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