Hi MartinV,
You ask;
MartinV writes:
Do you think there was a time M.maleo ancestors nested and hatched their eggs like other birds and only their descendants (more recent M.maleo ancestors) started burrying their eggs?
Well, I suppose that depends what you mean by other birds. Most birds are arboreal nesters and I cannot imagine that any megapode ever did that. They may well have nested on the ground, in a very simple nest, much like thousands of other bird species. At this remove we can only speculate (short of digging up half of Sulawesi looking for nest fossils) but there seem to be two possibilities; either the megapodes and their ancestors have always done this, right back to their Archosaur ancestors, or the behaviour re-emerged at some point, from a previously switched-off gene or a novel mutation. My bet is that the behaviour was always present. Maybe it got switched off/switched back on at some point, but I think the novel mutation sounds a bit much of a coincidence.
Fun to speculate, but it doesn't really prove anything.
Mutate and Survive
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