How dust mites distorted an entire ecosystem

Dust mites are everywhere, even in our own pores. Often they do a good job, in some cases they cause problems. In a population of llama-like animals in Argentina, they created a battlefield.

A Yale student had to interrupt her research in a natural park in Argentina due to the covid pandemic. Fortunately, by then she had already collected enough data to further investigate something very remarkable: the problems of a local vicuña population.

The population was declining. And rap too. The cause: a mite that lives in the skin of animals that have probably evolved from tamed farm llamas to this wild group of vicuñas. The mite lays eggs in the skin, which can cause animals to shed bits of fur and irritate the skin. It can get so out of hand that they become too weak to eat and eventually die. Isn’t it simply because they have become easier prey for the region’s pumas? No, cougar tracking data showed. They didn’t kill any more vicunas than before.

The rapid decline in vicuña numbers has also had an effect on the environment. The grass they normally kept short suddenly grew in all directions, the type of vegetation changed, and the vultures keeping a close eye on whether a mountain lion had taken a vicuña victim somewhere became less frequent in the park.

An entire ecosystem has changed, all thanks to a tiny mite.

Read more: How Mange remade an ecosystem