Though we know them to be dirty insects, cockroaches are actually incredible self-groomers. In fact, their grooming behavior ...

Artist's rendering of the Chicxulub asteroid entering Earth's atmosphere 66 million years ago, triggering events that caused a mass extermination. Roger Harris/Science Photo library via Getty Images ...

When conditions get too dry, Madagascar hissing cockroaches like to "cuddle". Under certain conditions, the large insects gather in groups, with many participants in physical contact with one another.

There is a particular kind of moment that triggers it. The light comes on. Something moves along the wall or across the floor ...