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It is my understanding that even though birds may be able to affect the
sex ratios of their fledgling, sex is not determined by inducation
   Consider temperature at three levels. The air (ambient) temperature,
the temperature in the microenvironment of the nest (nest T) and the
temperature within the egg (egg T). The latter is the most critical to
development and is regulated by the behavior of the parent on the nest
 and the temp in the nest when the parent is absent.  It is commonly
assumed that the temperature in the egg is maintained with adequate
precision to allow development to procees. Clearly, many of the processes
are biochemical in nature and chemical (and biological) process can be
temperature dependent. But the interactions at each level are flexible
enough so that development can proceed. And in fact despite all the
interruptions, pertubations and delays, hatching rates of birds eggs are
remarkably high.
   The conditions in dinosaur nests, and the reliability of the developmental
processes are currently unknown. There is not information on the presence of
incubation behavior (direct transfer of heat from parent to egg). One would
think that an unprotested nest on the ground (no evidence that dinosaurs nested
in trees) would 1. under wide temperature ranges, incompatable with development
and 2. be subject to predation. Consequently we assume that some simple
parential behavior occured, but we don't know--perhaps can't know--for sure.
                Alan Brush

 Department of Physiology & Neurobiology, University of Connecticut, Storrs