D: This Moment of Science is about one of the most widespread and stealthy carnivores in the Northern Hemisphere. This merciless carnivore traps, and then slowly saps the life out of its prey.
Y: Goodness! That sounds terrifying!
D: I know! Luckily we humans don't have much to fear. Mosquitoes, ants, and midges, however, had best take warning. That's because I'm talking about the butterwort.
Y: Aha! It's certainly true that the butterwort, or Pinguicula, is a fierce plant genus. After all, its eighty-odd individual species share a common carnivorous tendency, which surely strikes fear into the heart of small insects.
D: That's right. Since these plants tend to grow in areas where the soil is poor in nutrients, they require extra nitrogen to successfully produce seeds. And they've developed a ruthless tactic for acquiring that nitrogen.
Y: They sure have! You see, butterworts have leaves that lie flat on the ground, and function like flypaper. They secrete a sticky mucous substance, which makes the leaf look wet and inviting; it lures in unsuspecting insects...
D: ...And that's when the "ruthless" part begins. By landing on the sticky leaf, hapless mosquitoes and midges unwittingly sign their own death warrants. While struggling to escape, the insects trigger the release of digestive enzymes from the butterwort leaf. These enzymes slowly break down and liquefy the soft parts of the insect's body. Once the leaf absorbs this nitrogen-rich liquid, all that's left are a few indigestible remnants: a bit of hard skin, and the wings, and feet.
Y: Ugh. That sounds like something out of a horror film!
D: Yep. The butterwort might be a small-scale carnivore, but its hunting tactics are nothing short of terrifying, at least within the insect world!