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Re: What really happened 65 Ma ago (not a joke)



John Bois wrote:

> Firstly, almost all birds did die out.

Unknown...Just the facts, Sir.

Well, the "facts" appear to back up David... The Neornithes is the only bird clade that we know survived into the Cenozoic. Yet, there many other bird clades in the late Cretaceous (including enantiornithines); these did not survive. From a phylogenetic perspective, almost all birds did die out at the end of the Cretaceous.



Ron Orenstein wrote:

Well, there are many oceanic islands with endemic hawks that probably lack native predators but have not become giants (eg Hawaii, Fiji). The difference in NZ (as I see it) was the presence of large, heavy-bodied prey, coupled perhaps with climate (I say the latter because, for example, there seem to be no giant birds of prey known from places like, say, New Caledonia, which also featured at least one large flightless bird).

Cuba had a giant bird of prey, which I believe was flightless: the mega-owl _Ornimegalonyx_. I wonder if it was nocturnal?


There's also the roc of Madagascar, a giant predatory bird capable of picking up an elephant with its talons. Says Marco Polo:

"According to the report of those who have seen them... they are just like eagles but of the most colossal size.... They are so huge and bulky that one of them can pounce on an elephant and carry it up to a great height in the air. Then it lets go, so that the elephant drops to earth and is smashed to a pulp. Whereupon the gryphon bird perches on the carcass and feeds at its ease. They add that they have a wingspan of thirty paces and their wingfeathers are twelve paces long and of a thickness proportionate to their length.... I should explain that the islanders call them rukhs and know them by no other name."

Of course, the roc (rukh) is mythical, but no doubt inspired by _Aepyornis_ and its eggs. The elephant-grabbing abilities of the roc might be why _Aepyornis_ is commonly known as the "elephant bird", and not due to its impressive size. _Aepyornis_ (and _Mullerornis_ too) were herbivores. AFAIK, the largest flying predator in Madagascar is the endangered Madagascar fish-eagle (_Haliaeetus vociferoides_), which has a wingspan of about 2m.



Tim