Cats naturally live alone and have strong territorial instincts, but domestic cats frequently live in packs of one or more.
The hormone levels, gut microbiomes, and social behaviors of shelter cats living in groups were examined in a study that was published in July in the journal PLOS ONE to better understand how cats may have evolved to get along with people.

The findings revealed that cats with high levels of cortisol and testosterone interacted with other cats less frequently and were more likely to want to flee.
Cats with low levels of cortisol and testosterone were more accepting of one another. Cats who interacted frequently also exhibited more comparable gut microbiomes.
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