Does the Wave Function Collapse?

In quantum mechanics, wave function collapse occurs when a wave function—initially in a superposition of several eigenstates—reduces to a single eigenstate due to interaction with the external world. This interaction is called an "observation".

Can animals collapse the wave function?

So no, no animals have been used to collapse the wave function - it happens all by itself.

Does gravity collapse the wave function?

Gravity-related wavefunction collapse

In 1996, Penrose suggested that the collapse of quantum superpositions might be caused by the curvature of space–time – that is, by gravity. The effects of gravitation, he reasoned, are negligible at the level of atoms, but increase dramatically at the level of macroscopic objects.