the hyenas did it to kill mohatu (get him out of takas way)after that mohatu dies taka gets his scar the hyenas comfort taka like they didn't do a thing then the others find out and taka goes crazy!!!!
I might be very mistaken but... there's a stampede of buffalo running straight for Mohatu and Taka, Mohatu runs and picks him up and now he wants to hide him? Why? They are already out of the way of the buffalo and if one buffalo goes side tracked from the herd it could smash taka and the log. Isn't it kind of... weird... for Mohatu already know that the hyenas startled the buffalo if that's what this is and that's why he is hiding him? Because in the first panel of this page they were fine and Mohatu shouldn't have the need to have hidden him.