Obligatory disclaimer: real life sucks, but happy Canada day
everyone, all the same. May those who are better off in life than I am; enjoy
it all the same, wherever they may be! What next?
Let us get back to the vultures, but the Old World vultures
this time. Since there is quite a few of them, let us use the already-mentioned
cinereous vulture as a basic prototype.
Pause. What is
cinereous, one may wonder? Apparently, it is a pale ashy color, more grey than
black. There is a reason as to why the cinereous vulture is also known as the
Eurasian black vulture – it is more black in color than pale grey, so maybe we
should use its’ other-other name, the monk vulture, instead.
Why are we using the cinereous vulture as our Old World
vulture basic bird? Because of ‘Planet Earth’, which we have also discussed
before. In its’ ‘Temperate Woodlands’ episode, sir David had showed footage of
a mother and cub Amur leopards frightening those birds away from a kill during
a Siberian winter. Both leopards and vultures are usually associated with
tropics, not a Siberian winter, so ‘Planet Earth’ showed that both leopards and
vultures are made of harder stock than how we assume them to be. That said, the
cinereous vulture’s closest relative is the lappet-faced vulture of Africa and
the Arabian Peninsula, and neither of those places is known for winter snows,
so there is that. What next?
Climatic outliers aside, the Old World Vultures do come
across as slightly, bigger, tougher, and more varied birds than the New World
counterparts are. They include such atypical creatures as the lammergeyer,
which prefers to eat bone, the palm nut vulture, which eats palm nuts, and the
Egyptian vulture, which uses rocks to smash open ostrich eggs and eat their
contents. By contrast, the New World vultures don’t have such deviants, they
all are scavengers and carnivores… as are the bulk of the Old World vultures as
well; both the cinereous vulture and the lappet-faced vulture are known not
just to scavenge, but to kill live prey as well, sometimes fairly big one, such
as the wild lambs. Pause.
Let us get back to the taxonomy – whereas the New World
vultures’ closest relatives are not fully determined yet, (but they may be
storks), the Old World vultures are related to the hawks and eagles that we
have discussed earlier… another pause.
Let us get back to the eagles – to the white-tailed eagle,
for example. As we have talked about them, whereas falcons invested in speed,
and hawks – in endurance and maneuverability, the eagles invested in strength,
which cost them speed: their default method of movement is passively gliding
via warm currents of air, conserving their strength for when they need to
attack. The vultures utilize the same strategy, save that they do not usually
attack live prey, but scavenge from kills of other carnivores, which are
usually mammals.
Again, this is a mixed bag – for example, there is footage
of vulture flocks actually scaring cheetahs away from their kills rather than
patiently waiting for them to eat. Everyone dominates the poor cheetahs, it
looks like! ….Normally, however, carnivorous mammals such as big cats, wild
dogs, and – more rarely – bears will eat their fill, and only then will the
various birds, including the vultures of both types, join in. The birds may be
a more numerous and varied group of vertebrates at this point in Earth’s
history, but the mammals appear to be the more dominant one for now. Pound for
pound, mammals are more powerful and massive than the birds are, and so birds
have evolved to take advantage of the more successful mammals, which includes
the ancestors of the vultures, who had split from their eagle and hawk cousins sometime
in the past to become almost exclusive scavengers; some of them – namely, the
now extinct teratorns – were some of the biggest birds that’d ever flown… but
that is another story.
For now, though, this is it. See you all soon!
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