The “carnivore guild’ is an ecological concept describing a group of carnivorous species that harvest the same prey species, or at least have considerable overlap. They compete for prey, but they also compete more directly with each other, by attacking members of other carnivore species and stealing kills.
In Africa today, the carnivore guild is made up of lions, spotted hyenas, leopards, cheetahs, and African wild dogs – not counting humans. Lions are in first place, usually dominant, except sometimes when facing large numbers of hyenas. They end up with well over half of the kills – the “lion’s share”. Hyenas: a strong second, dominant over everything but lions. Leopards: avoid competition by hunting at night and from trees, but dominant over wild dogs and cheetahs. African wild dogs: regularly lose kills to lions and hyenas, and sometimes can dominate cheetahs. Cheetahs: fast but weak, must eat and run.
Different guild members do best in somewhat different landscapes. Cheetahs, fast sight hunters, prefer open landscapes. African wild dogs, cursorial hunters, need open areas to pursue. Lions prefer a mix of open plains and thicker vegetation. Hyenas are flexible. Leopards cache kills in trees to keep them from being stolen.
Stephen Churchill’s thesis, in his book “Thin on the Ground”, is that Neanderthals, who were largely carnivorous, were members of Pleistocene Europe’s carnivore guild – but not in first place. Cave lions and cave hyenas probably ranked higher. This means that Neanderthals were limited, more or less, to ambush hunting in wooded or hilly regions. Higher-ranking predators occupied most of the prime hunting grounds and got most of the kills.
This explains why Neanderthal population density wasn’t very high, why much of Europe doesn’t have many Neanderthal artifacts or fossils, and why Neanderthals didn’t cause any mass extinctions in their territory.
Pure predators don’t tend to drive their prey extinct, since when they over-hunt, their food becomes scarce, and their populations crash. Omnivores don’t tend to wipe out their prey, because they, being less specialized, tend not to have top rank in the predator guild… so their numbers are limited by other predators. Now, if you had an omnivore than was a better predator than any other, that was first in the predator guild – that species would be a hyperpredator, and would likely go on to cause mass extinctions. This is particularly the case for megafauna, which are very valuable targets, but also reproduce slowly.
Although not originally really effective at hunting, humans gradually became more formidable, as their tools improved, they learned how to make fire, and developed more complex behavioral strategies. By 400,000 years ago, they were routinely taking down elephants, but were not yet able to deal with the toughest African and Eurasian carnivores. How can we be sure of that? Because there were no megafaunal extinctions that early, or, any rate, not many.
A point: being #1 in the predator guild depends upon geography – on how tough the local predators are. It was pretty difficult in Africa, Eurasia, and the Americas: it was easier in Australia, and would been almost trivial on some islands.
So.. Neanderthals were not hyperpredators, and back 100,000 years ago, humans in general weren’t . except possibly on some islands that had few or weak predators.
There are hints that a population of modern humans (Population Y) arrived in the Americas before the Amerindians: if so, they were not hyperpredators, because there were no noticeable extinctions of megafauna back then. It also appears that they weren’t very numerous: they seem to have been “thin on the ground”, like Neanderthals.
Humans arrived earlier in Australia and megafauna extinctions soon followed. Those early Australians did not, as far as we know, have very advanced weapons, but they were still hyperpredators in an Australian context, because the local predators were really not up to the standards of lions, sabertooth tigers, and short-faced bears.
Probably the early Amerindians were the most clear-cut hyperpredators. They had stand-off weapons (atlatls) combined with long experience hunting fairly tough prey ( and dealing with tough predators) in Beringia. While the fauna of North America was not adapted to humans at all. Once the Paleo-Indians showed up, the megafauna didn’t have a chance.
This pattern was most dramatic when humans were encountering fauna that have never seen humans before – where the hand of man had never set foot – and had had no chance to evolve defenses. So megafaunal extinctions were rapid in Australia and the Americas, slower in Eurasia, incomplete in Africa.
West Hunter 