Welcome back to the Lab!
This summer has been filled with weekly bug hunts, and as we progress into August and the latter half of summer, our bug campers are starting to observe late-summer species. Yet, one arthropod remains present every week, and every time, inspires fear and awe among our young bug hunters: the daddy longleg.
Stop me if you’ve heard this one before: “Daddy longlegs are the most venomous spider in the world but their fangs are too small to bite.”
This is a fairly common statement that sometimes varies in its claim; some have told me the venom is powerful enough to kill. Some have told me the fangs are inverted. So let’s break down this common misconception, because not only is it ever-evolving, it is wildly incorrect.
For starters, Daddy longlegs (or Harvestmen) are not spiders. Arachnids, yes. They share similar features with spiders; they have an abdomen and cephalothorax, but their segments are fused so that they appear to only have a single, oval-shaped body segment. They have 8 legs, and the second pair has evolved to act like a pair of antennae. They only have a single pair of eyes, while spiders have 3 or 4, depending on the species. Some cave-dwelling harvestmen are completely eyeless.
Okay, so they’re not spiders. But what about their venom?
Simply put, they have none. Harvestmen do not have a sucking stomach, like spiders do. This means that they do not need to liquefy their food before they consume it. They are able to tear and eat chunks of their prey, which brings us to the third fallacy of the daddy longlegs rumor: without venom, there’s no evolutionary point for fangs (at least in the non-mammalian sense). Ergo, no fangs.
Until next time, thanks for visiting the lab!
Bug Wrangler Brenna
brenna@missoulabutterflyhouse.org
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