[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: The One True King
With some difficulty, I shall bite my tongue in restraint, and say: in the studies of ecomorphologies of dinosaurs, carefully analyzing each new specimen in the context of phylogenetic systematics, appreciating the awe-full magnificence of the animals...I find the endless verbiage over the "biggest" "baddest" and slash-and-tear sandbox iconographic totem meaningless. Does it matter if an individual theropod skeleton reveals measurements larger than the Chicago Tyrannosaurus? Of course not. Let me give an example: living spotted hyaenids kill up to 70% (if not more) of what they eat. Many of their killed prey are snatched by felids. And yet, a hyaenid has a biting power considerably greater than a lion, and a hyaenid pack is quite capable (and have) of turning on a lion and killing it in the darkness of an African night. Who is king? Neith!
, since both taxa are, in the main, hunting females. The subjective adjectives of "one true king" etc. etc. have no cladistic validity. We should be interested in how the animals lived...during an average 24 hour period, I doubt if a tyrannosaur walked about, mouth agape, roaring (there were no film crews about). Ask oneself a question: what was the tyrannosaur doing when not hunting or eating? What was a social group of tyrannosaurs like? Of dromaeosaurs? Of ceratopsians? Etienne Geoffroy Saint-Hilaire, the "father" of developmental evolutionary concepts, believed that one can use "actualism" to infer extinct behaviour systems by careful analyses of ongoing processes. Let me propose an example:
The John Hutchinson/Mariano Garcia tyrannosaur biomechanical study resonates with avenues of thought. When the animal was walking, was it a nasal breather? Nasal exhalation would warm and moisturize the air. If it broke into a very fast walk of, say, 10 m s, would the tyrannosaur use oronasal expiration? In this way, some air would be exhaled through an open mouth because the nasals would have increased resistance to air exhaled, i.e., when fast walking (I have watched human walkers in a race forcing a cameraperson to nearly run to catch up and maintain a similar pace) at some point the tyrannosaur would attain a balance, would be oronasal breathing. Among theropods with narrow nares (either from an ability to enter water and swim, or because it might have kept its head below water to catch fish), then it might be that, unlike other theropods, their nares could be occluded by inner valves to choking on water wh!
e grasping prey or even swallowing it. Now consider the physiology of the walking tyrannosaur: could the use of oronasal breathing have helped it maintain a higher rate of speed than a fast walk, i.e., could the oronasal breathing have enable it to break into a sprint for a relatively short distance vs. nasal breathing?