There is an old fable about a scorpion that rides on the back of a frog to cross a river (an alternate version has the scorpion riding atop a turtle). The scorpion can’t avoid its natural tendencies and stings the frog, causing both creatures to drown in the river.
Here is a real life story that sounds similar except that in this case the passenger, a raccoon, is the one that is in imminent danger. Never ever try to cross a river on the back of an alligator!
Fortunately, the raccoon figured out the “log” he was on was not a log and scurried away before he became lunch for the alligator.