Re: A megapode question

Hugo wrote "Evolution of the use of external heat sources for incubation must have included adaptations to egg/embryo physiology. Inadvertent turning may occur in the course of mound maintenance, but is not only unnecessary but also potentially damaging as megapode eggs have shells that are considerably thinner and more fragile than would be expected from comparison with those of other birds."

I doubted whether megapodes would turn their eggs deliberately (as Hugo also said "To what extent are megapodes 'aware' of their eggs, anyway?").  Egg shells are very thin (apparently 69% that of the expected shell thickness) so any disturbance is likely to be dangerous to the well-being of the egg.

Internal egg morphology does apparently differ from that of other eggs with the proportion of yolk to albumen very different.  It could well be that these eggs have adaptations to counter the problems associated with simply just "sitting in the dirt" waiting to hatch.

Isn't nature wonderful.  Anyway, it was just one of these questions that sometimes pops into one's head!

Cheers

David Geering
Regent Honeyeater Recovery Coordinator
Department of Environment & Conservation
P.O. Box 2111
Dubbo  NSW  2830
Ph: 02 6883 5335 or Freecall 1800 621 056
Fax: 02 6884 9382



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