Outside of the few that seemed cartoonish, the key signs seemed to be:<p>1) Furriness that seems a little too soft and fuzzy.<p>2) Overdone bokeh or depth-of-field.<p>3) Insect on a flower.
Aha, one of the main give-aways for me are the same as for AI-generated humans : number of legs!<p>Although there's a 10-legged blue spider in there that is allegedly a real animal.
First time: 3
Second time: 12
Third time: 24<p>Once you know, you know. But the beginning was really rough since the first few I got were so close. I think the cartoonish ones ruin it.