[SoftTalker]

It's a bit odd that the screwworm exists. Normally a parasite that kills its host is at an evolutionary disadvantage.

I wonder if the human practice of keeping large groups of livestock together in close proximity creates an unnatural "target rich environment" for the flies that they don't otherwise experience, making them much more of a problem.

[nine_k]

Ungulates very often gather in large, close groups in nature, in order to defend themselves from predators, and to conserve heat during night time.

[edoceo]

Can't we just compare this to "wild" population?