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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 (includi

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.

jcroll 9y ago
also bonus side dish
0xcafecafe 9y ago
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.
- meri_dian 9y ago
  There are so many of them that any individual is expendable. Beyond that, they don't need the other for survival (aside from strength through numbers) because they don't hunt. Lions and wolves hunt in packs, so the individual more directly contributes to the group's survival than in herbivore populations.
- xoa 9y ago
  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 9y ago
    That seems to make a lot of sense. Good write-up, thank you!
deleted 9y ago
[deleted]
ddoran 9y ago
Turn away if squeamish ... I saw a very similar thing on safari. The other attraction of hunting pregnant animals, our guide told us, was that the unborn animals are nutritionally dense. We did not witness the kill, thank goodness (I am squeamish!) but did see the aftermath - which was the lions extracting and eating the fetus first, while the mother was still alive. Nature is cruel.
- yakitori 9y ago
  > (I am squeamish!) Then why'd you go on a safari? > Nature is cruel. Nature isn't cruel. Nature is ambivalent.
  - oh_sigh 9y ago
    Multiple definitions of cruel fit nature, with no reference to willfullness: 3. causing or marked by great pain or distress: a cruel remark; a cruel affliction. 4. rigid; stern; strict; unrelentingly severe.

jcroll 9y ago

also bonus side dish

0xcafecafe 9y ago

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.

meri_dian 9y ago
There are so many of them that any individual is expendable. Beyond that, they don't need the other for survival (aside from strength through numbers) because they don't hunt. Lions and wolves hunt in packs, so the individual more directly contributes to the group's survival than in herbivore populations.
xoa 9y ago
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 9y ago
  That seems to make a lot of sense. Good write-up, thank you!

deleted 9y ago

[deleted]

ddoran 9y ago

Turn away if squeamish ... I saw a very similar thing on safari. The other attraction of hunting pregnant animals, our guide told us, was that the unborn animals are nutritionally dense. We did not witness the kill, thank goodness (I am squeamish!) but did see the aftermath - which was the lions extracting and eating the fetus first, while the mother was still alive. Nature is cruel.

yakitori 9y ago
> (I am squeamish!) Then why'd you go on a safari? > Nature is cruel. Nature isn't cruel. Nature is ambivalent.
- oh_sigh 9y ago
  Multiple definitions of cruel fit nature, with no reference to willfullness: 3. causing or marked by great pain or distress: a cruel remark; a cruel affliction. 4. rigid; stern; strict; unrelentingly severe.