Humanity is no stranger to the act of domestication. Starting with wolves around 15,000 years ago, we've successfully domesticated goats, pigs, sheep, and cattle to fit our narrative of the world.
Now, researchers in Australia believe they have discovered what they claim is the very first example of an animal domesticating another animal, per Griffith University News. This is especially surprising since, so far, the only other organisms known to domesticate others have been insects like ants which farm aphids, protecting them from predators to obtain that precious goo they excrete.
Researchers have found that a coral reef fish in Belize, Central America, and a tiny shrimp had a pretty tight relationship going on involving the tending of algae farms.
A mutualistic relationship that benefits species
Researchers, led by Griffith and Deakin University, found that the longfin damselfish domesticated the planktonic mysid shrimp and is using them to help fertilize their algae farm. Dr. Rohan Brooker from Deakin University’s Centre for Integrative Ecology stated, "We found highly territorial longfin damselfish and mysids have a mutualistic relationship that benefits both."
It was previously known that damselfish farm algae for food, The Conversation reports. According to the research, they use mysid shrimp feces as fertilizer and give the shrimp a safe place to live by chasing off any predators that swim too close to the farms.
They confirmed this notion by testing the protective nature of the fish and the quality of the algae and the health of the fish when the shrimp were around. When they put the mysids in a clear bag and placed them inside and outside a farm, they saw that those inside the farms were protected by the farmer fish. Moreover, the quality of the algae was much better when the shrimp were there to fertilize it with their feces.
William Feeney, the lead author of the study, stated, "The field studies and behavioral experiments we conducted at Carrie Bow Cay Research Station, however, provided evidence the relationship between damselfish and mysids bears all the hallmarks of domestication, not dissimilar to how humans keep farm animals.
"This is the first recorded case of a non-human vertebrate domesticating another species, and the first experimental evidence for a hypothesized pathway for how this domestication evolved."
The study has been published in the journal Nature Communications.