Cats are naturally solitary with highly territorial behaviors, but domestic cats often live in groups of one or more.
A study published in July in the journal PLOS ONE investigated how cats might have adapted to get along with others by looking at the hormone levels, gut microbiomes and social behaviors of shelter cats living in groups.
The results showed that cats with high levels of cortisol and testosterone had less contact with other cats; additionally, cats with high testosterone were more likely to try to escape.
Cats with low cortisol and testosterone had more tolerant cat-to-cat interactions. Additionally, cats who were in frequent contact had more similar gut microbiomes.