Bull and Donkey Form Sexual Bond in Ethiopia

Ethologists have documented a sustained sensual and affectionate relationship between a bull and a male donkey in the Ethiopian highlands of Debre Libanos. The animals, owned by different people, sought each other out and groomed one another amidst recurrent mountings.

This is no fable or comic strip: two male equids, one domesticated and one bovine, sharing pastureland in the Oromia region who, according to researchers, have turned casual encounters into something resembling a couple. The bull is named Achilles; the donkey, Patroclus. Ethologist **Elisabetta Palagi**, from the University of Pisa, leads the team publishing this work in **Current Biology**.

## Observations from March 6 to 19, 2026

The ethologists recorded all interactions involving either animal. During this period, they counted **51 mountings** between the bull and the donkey. It was not an isolated episode: the mountings recurred consistently throughout the observation days.

Alongside these mountings, researchers noted various affiliative behaviors: licking, rubbing, and nuzzling with their snouts. This repertoire is typical of close bonds between animals, not one-off encounters.

André B. da Cruz, biologist and neuroscientist, is another author of the study. According to his description, the two animals constantly chose to stay near each other and alternated these caresses with mountings.

## Two males with available partners nearby

The most significant detail in the study is the context. Achilles and Patroclus lived in a social environment where other potential partners were present, including individuals of both sens and their own species. They could have chosen someone of their own species and opposite sens. They chose each other.

Both belong to different owners and only meet when sharing pastureland. This separation of ownership did not prevent the bond from enduring over time. The relationship, according to the authors, was not occasional but continuous.

## Why a bull in love with a donkey matters

The association between a bull and a male donkey is not a behavior cataloged as common in ethology. The interest of the work lies in the combination: two different species, two males, and a sustained affective bond with recurrent sensual contact.

The study does not attribute the behavior to sensual orientation nor extrapolate it to other animals. It describes what peine in Debre Libanos during two weeks of observation and publishes concrete data: dates, number of mountings, and recorded behaviors. Any interpretation regarding what this means for other species, including humans, goes beyond what the article supports.