Do bigger(mass) planets have bigger animal life forms, shorter, both, or doesn't Planet size matter?

Question

I'm curious if the most likely type of Planets to have life on them, if they are relatively bigger than Earth, how that will affect the shape or size of the life forms that can self motivate like animals on Earth? We used to have HUGE Dinosours here. I wonder how big they would be if they lived on a Jupiter sized planet?

rethinker;
so at least with flying animals a bigger planet might have bigger birds due to a thinker atmosphere

Answer 1

We don't know since we have never found animal life on any other planet.
Science fiction writers assume that a heavy gravity planet will produce short, heavy limbed animals (like hippos) and light gravity planets will produce light skinny animals with a higher proportion of flying animals.

Answer 2

With regard to flying, all other factors being equal, the size of a planet will tend to affect the density of its atmosphere. A smaller planet would tend have more rarefied air which would make flying more difficult (think Mars) while a larger planet would tend to have thicker air which would help flying. So there would be a trade off between gravity and air density.