My guess would be big cats. I recall learning about early humans beginning to stand/walk upright in response to potential predation by lions and leopards - it’s easier to see the enemy. Not sure how much of that is true, but it would seem big cats would consider humans as a food source until we developed weapons and learned to cooperate as a defense against them. In modern times, perhaps the answer is the same?
Big cats, perhaps lions because I think there were more many more of them than tigers in the past, but I’m not sure. Possibly wolves in the past even though they aren’t a major predator now. But wolves are pretty smart and would go after easier prey than humans if they could. So it’s a guess, but over time I think it was lions.
If you go back far enough in time I think it will be a raptor dinosaur. They are reputed to have killed and eaten every human they ever saw.
If you’ll agree a mosquito is an animal, then those pesky little buggers gets my vote. IIRC, insects fall into the Kingdom: Animalia, making them animals.
On second thought, maybe fleas, due to the deadly diseases they have spread.
That…might be right, really. Over the whole course of human history cannibalism may have claimed the most victims, but you have to try to figure where to separate ritual cannibalism from actual huntin’ for meat cannibalism, which I imagine was less common.
After us, the various crocodiles taken as a whole or Nile Crocodiles in particular is probably a good guess. Lions and tigers both had huge historical ranges, but I’d make a very wild guess at tigers being slightly more prone to kill people than lions just due to habitat if nothing else ( as a generality lions seem to prefer slightly more open country ). Certainly in historical times tigers seem to have killed far more people, probably at least partly a function of their historical ubiquity in densely populated India ( lions were and are in India, but in far more restricted regions ).
Probably none of it. The most accepted hypothesis is that upright walking evolved as either a heat regulating mechanism or a walking efficiency mechanism (or maybe some combo of them both). The “man stood up to see over the grasses” hypothesis was thrown around a bit 40 years ago or more, but not much since then.
The problem with snakes (I saw a graphic on IFLS recently that showed snakes in 3rd place, after mosquitos and humans, at least in he modern age) is that most of them do not actually eat the humans they kill.
The correct answer is probably one of the big cats or crocodiles, but I’m surprised no one else has even mentioned bears. Granted very few deaths occur due to bears in modern times, but that’s mainly because nearly every bear population has been decimated, a large portion of the genus has recently gone extinct, and bears have adapted over the years to humans by switching from a primarily-meat to primarily-plant diet. But they could easily hunt and kill humans and exist on every continent except Australia and Antarctica. They stay away from us now because we usually kill them, when people were less able to defend themselves I could see bears taking advantage.