A group of crows is a murder. A group of monkeys is a troop. I guess a group of rabbits is apparently called a fluffle? I found dozens and dozens of these just poking around on Google.
When did we start calling groups of animals by, uh, unique names like this? Who decided on all of these, and why did society at large follow suit?
I asked a similar question about a year ago, answered by /u/Litrebike. The general gist is that they originate from "terms of venery," which were used in the context of hunting by the nobility. They played into broader trends in noble culture as a way to display one's sophistication and familiarity with the social aspect of hunting, and from there filtered down into vernacular currency.