New speculations on dinosaurs
Creationists are generally interested in any new ideas on dinosaurs, even when these do not directly affect the creation/evolution issue. For example, there has been a recent affirmation that dinosaurs, unlike today’s reptiles, were probably warm-blooded.
A physiologist from the University of Adelaide’s Zoology Department, Dr. P.S. Seymour, has done research into two other aspects of these fascinating creatures. The first concerns those huge necks which some of the larger ones are drawn with, holding them high up in the air (e.g., Apatosaurus). He had previously been involved with work on snakes when he discovered that some snakes can not function well with their heads held high because the blood pressure is not enough to send blood to the brain in that unaccustomed position. He then wondered what happened in sauropods, some of which were thought to hold their heads as much as nine meters above the ground. When he calculated the pressure needed, it was very high—around 600 mm of mercury compared with a human blood pressure averaging around 100 mm. Using this to calculate what sort of heart was needed, he found that he was unable to design a heart sufficient for the job. According to Dr Seymour, ‘The heart would have to have been so big and so thick that it could not possibly have operated efficiently.’ So he concludes that either they walked with their heads stuck out in front of them or they were aquatic. While not necessarily disputing these conclusions, we would point out that we know nothing concrete at all about dinosaur physiology, and that it seems presumptuous to assume that because a modern physiologist, armed only with knowledge of today’s cardiovascular physiology, is unable to design a heart suitable for the job, therefore it is impossible. Such reasoning presupposes that there was no Creator able to endow each creature with structures suitable for its unique needs, but that we are bound in our analysis to using only existing heart designs with slight modifications.
His other study is a microscopic analysis of dinosaur eggshells lent to him by the British Museum. He discovered that the shells were very porous, about eight times more porous than a bird egg of the same size. Eggshells have pores to allow free exchange of gases with the environment. Because of this porosity, Dr Seymour concluded that if they were laid above ground, they would dehydrate before the embryo could develop. The porosity and also the nature of some of the fossil sites seem to suggest that the eggs were covered by moist vegetation dragged into great mounds by the banks of rivers, with four or five eggs at a time being deposited in them.
Dr Seymour’s paper will be presented this month at an international symposium in Paris on ‘mesozoic ecosystems.’