What the hell was a possum doing in that pumpkin!? I'd say it was maybe the wrong place, wrong time...:-)
I googled ... opossums like to eat pumpkins. So maybe he had gotten inside, by eating thru the bottom (hidden from view). The opossum riding on the back of the alligator could have two origins ... one ... baby possums ride on the back of their mother ... two ... an inversion of the old scorpion vs the frog ...
"A scorpion asks a frog to carry it across a river. The frog hesitates, afraid of being stung, but the scorpion argues that if it did so, they would both drown. Considering this, the frog agrees, but midway across the river the scorpion does indeed sting the frog, dooming them both."
Seems a parable for American politics.