Eating poison to get a date
Male animals can do some strange things to get the attention of females. Great bustards, for instance, knowingly eat poisonous beetles in order to impress potential mates. Especially during mating season, the males do this to ‘brag’ about being tough and enjoying good health.
This behaviour, however, has been shown to be useful in another way as well. The toxic substances in the beetles kill parasites in the male’s cloaca. Besides being where faeces and urine leave the bird’s body, the cloaca is also a reproductive organ. Female great bustards inspect the male cloaca thoroughly; it is dark and thus easy to see against the backdrop of white plumage. Only when the cloaca is truly free of parasites – thanks to the poisonous beetles – is the female ready to mate.