Multiple species of spiders have independently evolved to look like ants.
This convergent evolution happened at least 70 different times where they all evolved to look like ants but did not inherit this trait from a common ancestor.
These ant mimicking spiders often prey on individual ants, or hide in the colony for protection from its predators.
Speaks to how wide spread and successful ants have been that it changed the appearance of multiple spider species over the course of millions of years.