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NERC and the Nuptials
By Paul Hopwood - University of Exeter
Glasses chink, guests coalesce and I find myself sitting among six prim strangers; another wedding reception begins…
“Estate agent! Did you taste this dip?”
“Internal relations, how are you getting on?”
“Me? I’m a student,
Yes a loan, and a NERC grant,
No not a BMW, a bicycle.”
“Well actually I study beetles…”
I start to enthuse; my wife throws me a knowing, cautionary glance.
“Actually, beetles are pretty important creatures; about 25% of all known animals are beetles (that doesn’t sound plausible––phones flash wiki-factoids) and the beetles I study stand head and thorax above even this crowd. Burying beetles bury dead animals; a small sad corpse serves as nursery and larder combined. They care for their babies, like blackbirds do, and they have some devious strategies for success.”
“OK, well for biologists success means producing more or better offspring than average… yes we have a daughter too, er, she’s two”
“no, thanks; I’ve had enough wine for a minute”
“…For burying beetles one problem is that small dead bodies can be few and far-between. Without enough carcasses to go round burying beetles must have flexible talents to make the most of difficult times and capitalize on good times. They have a variety of tactics including cheating on each other, brawling over romance and off-loading household chores––and children, but ultimately, if they get a chance to ‘settle down’ they’re great parents. Both parents will help prepare food, feed the babies, clean the nursery and make sensible, joint family-planning decisions (they eat any new-borns they can’t afford to keep). Very few insects have a family life like this so we study these hoping to figure out why complex parental behaviour evolves in general.
Unpredictability of food resources might be key. Dead animals don’t last long so burying beetle babies must grow fast. A hard week regurgitating carrion into tiny mouthparts gives youngsters a good start and anyway the chance of finding another carcass is slim. Mind you, if you’re a super-good-looking dad it might pay to desert the family for a mating spree. If your powers of mate attraction are much better than the average male, you could leave a trail of single mums, and buff larvae fathered by you could be cared for in unsuspecting rivals’ corpses.”
“Oh, is it us for the buffet?”
Burying beetles, Nicrophorus vespillo, caring for a brood of offspring (male: upper - feeding larvae; female: lower - processing carcass). Note uneven distribution of phoretic mites between beetles: perhaps they anticipate this male’s early desertion, i.e. they’ve boarded the next flight out.