Told you they were evil...

BBC - Earth News - Males make pregnant horses abort

Horse breeders, including thoroughbred breeders in the UK, often send mares to stables to be mated with stallions.

But a study reveals that, when they return, the pregnant mares engage in "promiscuous sex" with males in their home stables, in an attempt to disguise the paternity of the foal.

When this is not possible, the mares often abort the pregnancy.

So, they look dumb and are depraved. I miss the days when animals were put on trial...