A survey of 50 houses in North Carolina reveals that Americans share their homes with an average of 93 species of insects, arachnids and other arthropods.
In all, 10,000 specimens comprising nearly 600 species were recovered from a total of 554 rooms.
Many of the species, including bedbugs, house spiders, book lice, carpet beetles, house centipedes, silverfish and cockroaches, have a long evolutionary history of living and breeding in human dwellings.
“Our homes could be seen as extensions of our cave-dwelling past,” said lead researcher Matthew Bertone of North Carolina State University.
Other species, such as ants, only enter homes to forage. Then there is what Bertone calls “aerial plankton” – animals that enter houses accidentally and are unable to escape: “Our houses are very effective insect traps.”