City birds use cigarette butts to smoke out parasites [1]

I find this amazing, how animals seem to have this inherent understanding of natural remedies. Humans have this ability too, though we've become so out of tune with Nature that few are really connected with that part of themselves.

Stuffing cigarette butts into the lining of nests may seem unwholesome. But a team of ecologists says that far from being unnatural, the use of smoked cigarettes by city birds may be an urban variation of an ancient adaptation.

Birds have long been known to line their nests with vegetation rich in compounds [2] that drive away parasites. Chemicals in tobacco leaves are known to repel arthropods such as parasitic mites, so Monserrat Suárez-Rodríguez, an ecologist at the National Autonomous University of Mexico in Mexico City, and her colleagues wondered whether city birds were using cigarette butts in the same way.