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Re: Phorusrhacids killing large mammals in National Geographic Channel

Graydon wrote:
> Extant wolf populations are remnants everywhere.  This is not true of
> the African wild dogs or hyaenas.

With remnants you mean, small populations vulnerable to extinction? In
such a case, this is also true of African wild dogs. Also, I am not so
sure the danger a species or population have has to do with the care
the individuals of a pack put in preserving their own lives... (I
suppose they have little worry of the future of their species).
Although I think an individual has better chances of bring descendants
when other individuals (overall of the other sex) around, group
selection is somewhat complicated to prove...

> Assuming from the limbs that a similar running ability is true of
> phorusrhacids is only useful for prey capture if it's chasing a
> cursorial herbivore that will try to run away for long enough that it
> can be run to exhaustion, but it's certainly going to be useful
> defensively.

True, I think this may be related with the air sac system and red
muscles at the legs (permitting more resistance, common in walking
birds such as chicken), which would be likely present in
phorusrhacids, which would be largely walking birds.

David Marjanovic wrote:
>>  Something similar to the lateral shaking of dogs can be observed in
>>  this gull, admittedly in not so great frequency, so it may not be so
>>  unlikely to occur in other predatory birds:
> It's widespread in predatory birds. Even quetzals do it (the adults are
> rather herbivorous, but they feed their young with large lizards).

Wow, I believe you, but never saw it in nature shows such a thing. I
do not see much Nat Geo, Discovery, and Animal Planet now as I used to
do once, but I am surprised not remembering that even taking into
accoun how much these shows overrepresent the killing or severely
harming of an animal by another over all the other behaviours of
animals. I do not know of reports in the literature of such things,
which are more of interest of childs with a Goku vs. Vegeta mentality
than to mature scientists.