
How big cats hunt zebras and impalas, and how these prey flee their predators - Jerry2
https://www.nytimes.com/2018/01/24/science/cheetahs-lions-zebras-impalas.html
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anon1253
I was lucky enough to visit a private game reserve in South Africa for a few
days. One of the things I saw was a pregnant ex-Zebra being eaten by lions
(including the fetus that was dragged to the shade under a bush by other
Lions). The guide explained that what likely happened is that the lions tried
to separate the pregnant zebra from the herd and make her go down slope. The
added weight of the fetus makes maneuvering down slope harder, especially when
trying to make tight turns, giving the lion the edge. It was fascinating
(although a bit gruesome) to see animal behavior in action that way.

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0xcafecafe
I always wonder for the herbivores why does "the saving your own kind"
instinct not kick in more often. A lion is more powerful than a zebra but
there are cases like a herd of bison running away from wolves who are trying
to isolate youngsters. If they stay put and don't blink the wolves have no
chance. A recent documentary episode I saw (I think in frozen planet or the
hunt) had an extreme case of a pack of wolves trying to bring down a juvenile
bison and an adult just running through the struggling juvenile, bringing it
down and making it easy for the wolves.

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xoa
r/K selection theory has been subsumed by more advanced theories over the last
few decades, but many of its themes are still applicable and it provides a
simple way to think about some general reproduction strategies. Herbivores
fundamentally have far more energy availability, because they're a level
closer to the primary input of the sun (Sun -> plants -> herbivore, energy for
useful work lost at every conversion step), and in turn many of them follow a
more r-selection strategy where they have lots of offspring with lower
investment in each individual one, and huge populations of which significant
numbers die young (from predation, accidents, starvation, disease, etc) but
enough survive through quantity. Conversely this can actually make healthy
adults more valuable then any single young one, since they represent a success
that can and will breed many many more times.

In contrast big predators sink a lot more energy and time into each individual
juvenile, and have far fewer of them. You'll notice that with many highly
mobile herbivores juveniles come out and are ready to walk and begin moving
with their parents/the herd in very short order without an extended period of
total helplessness.

Herds do have to keep moving to find new food supplies, so staying in place
indefinitely is not an option. They generally are much faster in a straight
line then most predators too, so they can in fact outrun them (and in turn
predators are forced to deploy tactics, go after ones with restricted mobility
which takes more function to recognize, and so forth). These various pushes
and pulls on selection have resulted in the successful strategies we see each
species deploy. The emergent effects of life really is incredible as trite as
it may sound to say it. Such incredible complexity driven by basics that are
pretty straight forward.

~~~
0xcafecafe
That seems to make a lot of sense. Good write-up, thank you!

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Theodores
If anyone else found that unsatisfying, here is a recent book that does a
better job of telling the story of tracking animals:

[http://wheretheanimalsgo.com/baboons/](http://wheretheanimalsgo.com/baboons/)

[https://www.amazon.co.uk/gp/product/1846148812](https://www.amazon.co.uk/gp/product/1846148812)

More generally when it comes to tracking animals...

What I want to see is facial recognition for animals, so that some one-way
hash resolves to a name, so anyone who pointed their phone at a particular
bird would reliably get the name determined by the facial recognition hash, so
it could be consistently a 'Trevor' for instance. Of course 'Trevor' could be
tagged in photos in this bold new future of 'facial recognition for birds' so
it might be possible to find him in lots of different social media posts with
different people and in different locations.

By default 'Trevor' would have a shadow Facebook profile complete with shadow
profile links to his other half, mum and the rest of the flock.

More seriously, I do wonder at applications for this alt-coin circus that has
come along and whether a large database of every living creature on the planet
could be magically possible using these magic blockchain technologies.

So, very much tongue in cheek, when it comes to implementing 'facial
recognition for birds, hamsters and many tens of thousands of species', how
would the 'ICO' work out?

I am sure this could all be easily done and coded up by next Friday by a
teenager if it was based on blockchain technologies with coins being mined by
adding new animals to the distributed database photographically. To lure ICO
bitcoin-bores in this magic database would be super fast because it would be
modelled on DNA and therefore compact, albeit forked on a per-species basis so
fish coins could be traded for apex primate coins but not necessarily vice-
versa. All of this blockchain could solve the hard problem of digital rights
management, so if 'Trevor' appeared in the back of one of your selfie pictures
then the micro-payment for that would pay out with 'Trevor' getting his share
of Instagram likes.

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surfrider
You have to watch the SafariLive Channel on Youtube. They are live everyday
and they dont shy away from the hunt. amazing stuff.

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wiradikusuma
I think, it would be much better if they provide visualization or even video.

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a_c
TL; DR:

> Though cheetahs and impalas were universally more athletic than lions and
> zebras, both cheetahs and lions had a similar advantage over their prey —
> they were 38 percent faster, 37 percent better at accelerating, 72 percent
> better at decelerating and their muscles were 20 percent more powerful.

> [...] impalas and zebras were typically moving at only half their maximum
> speed. [...] The model showed that impalas and zebras have the best chance
> of making a getaway if they run at moderate speeds, because that leaves more
> options for maneuvering away at the last second

~~~
jwilk
> _Though cheetahs and impalas were universally more athletic than lions and
> zebras_

Wait, what? Did they mean that _cheetahs and lions were more athletic than
implalas and zebras_?

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icegreentea2
No, I think they mean they meant exactly what they wrote. Impalas are too fast
for lions to hunt (normally). Single cheetahs are too small to take down a
zebra (normally).

~~~
gus_massa
Impalas and zebras must be more athletic because they have to scape the
cheetahs and lions 100% of the time. If you scape only 99% of the time you are
dead.

Also, the predator is happy to catch any of the preys, they can pick a
tired/old/sick/unlucky one. So if 99% of the prey scape, they are probably
happy.

~~~
Retric
You don't need to be faster than the predator, you need to be faster than
other members of the herd.

~~~
mywacaday
Reminds me of the Billy Connolly joke about the two camera men filming a lion.
The lion sees the two camera men and proceeds to chase after them. One camera
man stops and puts on a pair of running shoes. His colleague tells him “You
will never outrun the lion in those”. He replied, “I don’t need to outrun the
lion, I just need to outrun you!!”.

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jwilk
Please use the orignal title.

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ObeyTheGuts
Thats how i play basketball, i do not go 100% all time as then defence can
easy predict my motion, instead i go half speed and burst in speed when
needed.

