A few theories are that he got damaged in the collision with a tree and died from internal bleeding then his body was picked at by scavengers, or that he waspicked off by Raptors as they seemed to land right next to a Raptor nest.
All we know for sure is that it was not a BIG dino that done it as there would be nothing left of him.

No one will ever know and it doesn't make any sense since he helped Eric get down first.
Then the parents are like, "Fuck him. Let's move on and find our boy!"
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My guess is that he rotted.

I always assumed the compys got him.
Presumably he was already injured bad and didn't wanna drop down and told Eric to go look for assistance somewhere.

Didn't the predator take him out?

I'm much more interested in "how he lived"

Logical explanation: When he dropped Eric out of the parachute and Eric notices the camera still on and turns it off. After this i'd say they were probably ambushed by raptors (which happens multiple times in this movie), Eric somehow managed to hide/get away but Ben couldn't get himself unstrapped from the parachute quick enough and the raptors picked him clean.

That is what I thought had happened to him too. That he got tangled in the parachute and dangled around where it got caught. Some raptors saw him and proceeded to feast on him by climbing up where he was. The boy who was with him could not do anything about it.

I've heard in the script (or the original one, at least), the raptors get him.
Cena doesn't overcome any odds. He's a wrestler with a God Mode cheat on.

Maybe his throat/jugular was ripped out (or another vital artery and/or vein) before a second dinosaur came by and scared the first one away OR fought the first dinosaur until both were distracted and far from Ben's dying body.
Then, small scavenger dinosaurs (perhaps procompsognathus) wandered by, attracted by the scent of now rotting flesh and took parts away from him until he was just a skeleton.
It is a tale told by an idiot, full of sound and fury, signifying nothing
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The thought occurred to me as well, but his skeleton is intact! No damage at all, I know it's just a little thing but it's really been annoying me every time I watch this movie, haha.

It's possible he was attacked by a nearby dinosaur.
It is a tale told by an idiot, full of sound and fury, signifying nothing
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