Do any animals other than humans commit suicade?

The whole lemming thing is an urban legend. There was a horrible movie about animals made by Disney some years back in which many scenes were staged or faked. The lemming scene was one of them, completely faked, but it was enough to convince a lot of gullible people to start talking about it.

If your definition of “suicide” is broad enough, there are plenty of cases of animals becoming so depressed or traumatized that they will refuse food or engage in self-destructive behavior until dead, birds and dogs being prime examples, but since this isn’t exactly SEEKING death, more of a side effect of their emotional state, it’s not really suicide.

There’s also cases where scorpions will sting themselves to death in high-stress environments, but it is unlikely that scorpions have a sense of their own mortality when they do this.