Stories tagged larva

May
17
2012

How'd you like to wear jewelry made by a bug? Right off the bat, it might not seem like a very appealing idea. But read on, my friend, read on...Caddisfly larva: Imagine this, but made of gold.
Caddisfly larva: Imagine this, but made of gold.Courtesy Wikimedia Commons

I'm a volunteer at the Science Museum of Minnesota, and I'm training for our Aquatic Invertebrates demonstration. I'm a linguist, not a biologist, and I know hardly anything about bugs, so of course I thought it would be neat to learn something about all the little critters you might find in a Minnesota pond or stream. What I didn't anticipate is the utter awesomeness of one particularly enterprising little creature, the caddisfly larva.

Insect larva like the caddisfly are crucial to a stream's ecosystem because they eat dead leaf matter and algae that would otherwise clog up the stream and choke out other life. An insect larva is generally a pretty small, helpless little thing, though, and can make easy fodder for fish and other aquatic animals. The caddisfly larva is no fool, though: it protects itself by building a tiny tube house out of the materials available in the stream, like bits of sand and gravel, tiny sticks, pine needles, and so forth, which are stuck together with silk that the larva excretes.

Of course, a caddisfly is just doing what it's programmed to do, and using whatever materials it has on hand. I mean, hand-analogue. It's an insect; it doesn't have hands. Anyway, the point is that a caddisfly that finds some pine needles will make a little pine needle case, and a caddisfly that comes across some gravel will make a gravel case. That means that if you give a caddisfly larva little chips of turquoise, or pearls, or gold, you get beautiful, jewelry-worthy caddisfly tube "beads". Take a look at some examples.

It's Friday, so it's time for another Science Friday video. Science Friday
Science Friday
Courtesy Science Friday
Today,
"New Caledonian crows are among only a handful of species on the planet that have been shown to use tools. They use twigs to fish out beetle larvae from dead trees. Reporting in Science, Christian Rutz and colleagues explore why the birds evolved to have this rare trait."