While decorating the office with the last of our giant fake Halloween spiders last week, the EcoMyths team was inspired to explore the age-old question, “Are bugs really out to get us?” Today on Worldview, Jerome McDonnell and I had two experts on the hot seat: Corrie Moreau, PhD, an ant specialist at the Field Museum, and David Wise, PhD, a professor at University of Illinois at Chicago and an authority on spiders.
Bottom line, although insects and spiders may look really creepy to us humans, most are actually trying to avoid people and instead, going about the business of being bugs. For spiders, we all know this entails weaving webs and catching other bugs that wander too close. Spiders are mostly loners and rarely interact with one another except to eat one another when hungry. On the other hand, the daily business of ants takes place in a community. Ants build nests together and capture prey to take back to feed the larva babies in the nest. Often ants capture much larger creatures, like crickets, and seemingly miraculously haul them back to the nest single-handedly.
So where does the human fear of bugs come from? Our experts suggested that it may have to do with how and what insects eat. Both Corrie and David agreed that the predator vs. prey interactions of bugs is especially fun for them to study.
Spiders, David told us, are highly cannibalistic. They will eat anything they can capture, including their own species. However, spiders are not at all interested in biting people and won’t bother you if you don’t touch them. It is a myth, he says, that the bites you find on your arms and legs when you wake up with in the morning are from spiders. He cited a hospital study which found that most of the bites people attributed to spiders were actually from other insects.
You may not expect a tiny little ant to leer at you and sneer “I vant to suck your blood!” But ants, while not particularly fearsome, offer a few species with creepy-sounding names like the Dracula ant. Corrie indicated that the Dracula ant gets its name because the adult’s only source of nourishment comes from feasting on the blood of its larva babies. They do this out of necessity, not just to creep out sensitive humans.
Like all ants, adult Dracula ants have tightly constricted necks and waists, so they cannot eat solid food like the larvae can. “Sack with a mouth” is how Corrie describes a typical ant larva.
Larval baby ants can chew and consume a prey animal, such as a cricket, and do so on behalf of the adults as well as themselves, usually regurgitating to create dinner for the adults. In the case of the Dracula ant, Corrie described a scene in which the adult “pierces a hole in the skin” of the larva and licks up the blood and fluid that emerges.
As I told Corrie, it makes me glad to be a human rather than an ant! Though it could make for a disgusting Halloween haunted house scenario…
— As part of our partnership with Chicago Public Media/WBEZ, this content may also appear on the station website.