Carrion Beetle
Okay, this bug is so freaking cool that it gets a two-day run. Tomorrow we’ll flip it over and talk about its underside. This is a carrion beetle, Nicrophorus tomentosus. It’s about 20mm long, and it walked out of my lawn last Saturday. Special thanks are due to bugguide.net for ID’ing this one for me.
Carrion beetles need a tiny corpse, such as a dead mouse or vole, in order reproduce. When they find one, they use pheromones to attract a mate. After mating, the male and female stay together until their young are raised.
As with any healthy relationship, the first thing the young couple must do is hide the body. Over the next 24 hours, they bury the corpse and dig a crypt around it, stopping to mate, on average, about 70 times. (Ah, newlyweds!) Then the female lays eggs on the body. After that, she will spend most of her time tending the brood and the male will guard the crypt, though the parents will occasionally switch off to relieve the monotony. If one of the parents dies, the other one will assume both duties and the brood still stands a pretty good chance of survival.
I always find amazing things when I look at bugs. For example, when the female carrion beetle reaches maturity her ovaries develop and all the preparations for reproduction are made, but then the whole process just stops, almost like she has laid a foot on the pendulum of her biological clock. When a male attracts her, she checks out the male, inspects the corpse by patting it with her forelegs and antennae, and she even inspects the ground to see if it is suitable for digging. Then, and only then, does she choose to ovulate: her body floods with hormones and she and her mate get to work digging (with the aforementioned frequent pauses).
If more than one beetle finds a corpse, the males will fight amongst themselves, and the females will do likewise, until all but the strongest of each gender have been driven off, and the winners of each gender will mate. If the corpse is large, more than one female may colonize it; if it is particularly large more than one mating pair may colonize it. What fascinates me is what happens near moderately large corpses–large, but not quite large enough to support multiple broods. The male will continue signaling to attract females… at which point the female on the scene will physically interfere, by pushing him over, jumping on top of him, and pinching him with her jaws.
I think it’s kind of sweet. She’s ovulating for him, she’s going to dig a crypt with him, and she’s going to raise a brood with him for the next several weeks. I think she’s entitled to a little jealousy.
Slowly getting the site back onto an even keel. It's nice to get back into the old posting rhythm.
tceisele said,
November 6, 2007 @ 8:09 am
I see something coming around the underside by the edges of the wing covers. It looks . . . squirmy. Is this a surprise for tomorrow’s picture?
Seth said,
November 6, 2007 @ 9:00 am
Awww… I hope to have as deep and meaningful a relationship as the Nicrophorus tomentus does someday. *sighs wistfully*
David Brady said,
November 6, 2007 @ 10:38 am
tceisele: I’m not telling!
Seth: Me too, though I’m not sure I’d survive the wedding night.
Blógünder Schlock » Blog Archive » “As with any healthy relationship, the first thing the young couple must do is hide the body. “ said,
November 8, 2007 @ 2:03 am
[...] Yesterday’s Insectpod.com deserves a read. [...]
Andymatic » Nympho Homicidal Carrion Beetles said,
November 10, 2007 @ 3:56 pm
[...] to attract a mate. After mating, the male and female stay together until their young are raised. As with any healthy relationship, the first thing the young couple must do is hide the body. Over the next 24 hours, they bury the corpse and dig a crypt around it, stopping to mate, on [...]
Nick said,
August 29, 2008 @ 12:48 pm
I’ve been observing a prehistoric age looking bug hanging around the hunting camp skinning rack for years. They appear to be the larvae of a type beetle or something, they definitely eat, or seem to be eating the left behind remnants of the deer processed at this location. If I send a picture, could you identify this weird looking bug please? Could it be the dermisted beetle? Please help if you can? nc
stephanie said,
August 30, 2008 @ 1:14 am
There are no words to describe my horror and disgust for this…incredible creature I discovered while I thought what I saw was a big cute bumblebee buzzing around in my room until……
(just thought i’d comment this after i was trying to figure out how to spell it’s name by stumbling on this site…lol)