One species of termite sends its older workers on suicide missions armed with explosive blue "backpacks."
When grabbed by another termite, a predator or a person with tweezers, these backpack-sporting termites, which the researchers call blue workers, rupture and spew a toxic, sticky substance, scientists have found.
The unfortunate workers from this species of tropical termite, Neocapritermes taracua, have two bluish spots visible on the backs of their abdomens. These spots contain crystals made of a copper-containing protein stored in two external "backpack" pouches, write the researchers.
The crystals react with the salivary gland secretions stored in their abdomens to create a droplet of toxic goo that can kill or paralyze worker termites from another species, Labiotermes labralis, an experiment revealed. [Video of Exploding Suicide Termites]
So-called white workers also have the salivary secretions but lack the blue crystals. These workers are less aggressive, slower to burst in battle and the substance they produce is not as effective against their enemies.
The researchers transplanted the crystals from blue workers onto white workers, and found the white workers became more deadly once they had the crystals.
They also determined that the blue workers were older by measuring the length of the edge of the termites' mandibles. Termites chew on wood and as they age their mandibles wear down. The larger the blue crystals on a termite, the more blunt its mandibles, the researchers found.
Among social insects like termites, the practice of sending older workers into battle is common, researcher Yves Roisin of Université Libre de Bruxelles in Belgium said in a podcast interview released by the journal Science, where this research is detailed.
"[Among] such insects of course the individual doesn't really count or it counts by the work it can actually do for the colony, and when they are old and probably less efficient they are more likely to sacrifice themselves," Roisin said.
However, the blue workers' suicide gear is highly unusual in the world of insect warfare, because the combination of blue crystals and salivary secretions make it a two-component system, Roisin said, adding that it is also exceptional that one component (the crystals) is carried outside of the body.
So far, the researchers have seen this behavior in this species only, but they hope to see if its relatives do something similar, he said.
The research appears in Friday's (July 27) issue of the journal Science.
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Angler Fish: Just A Little Clingy
The next time you think your mate is getting a little too attached, just be glad you're not an <a href="http://www.bbc.co.uk/dna/h2g2/A22547838" target="_hplink">angler fish</a>. According to an h2g2 post, when a male angler fish finds a mate, he clings on for dear life. Perhaps because the angler fish is so horrifyingly unattractive, he feels that any less drastic measure would surely lose her. Thus, he bites into her, attaching himself permanently, linking his blood supply to hers. While she provides nourishment to him, he offers her sperm whenever there are eggs to fertilize. Fair trade-off?
Octopuses: A Man's Greatest Fear
A man's greatest fear? Discovery Science reports that in the <a href="http://science.discovery.com/top-ten/2009/mating-ritual/mating-ritual-01.html" target="_hplink">octopus</a> world, it's actually expected that a male's penis will break off during mating. Fortunately, it grows back in time for the next mating season.
Hippos: Where Poop Is A Turn On
There may have been a "Jerry Springer" episode about this... A male <a href="http://science.discovery.com/top-ten/2009/mating-ritual/mating-ritual-10.html" target="_hplink">hippopotamus</a> attracts a female by spraying her with his feces, Discovery Science reports. And who says bathroom talk isn't sexy?
Flamingos: Just A Touch Of Makeup
Flamingos may use pigments from gland secretions to improve the color of their feathers, thus attracting better mates. A <a href="http://www.sciencecentric.com/news/10102624-beauty-from-the-bottom-up.html" target="_hplink">study</a> from the Estacion Biologica de Donana in Spain found that there was no particular reason for flamingos to alter their colors, except for mating purposes. L'Oreal and Maybelline should look into this new potential client base.
Midges: It Sucks
A <a href="http://science.discovery.com/top-ten/2009/mating-ritual/mating-ritual-08.html" target="_hplink">midge</a> engages in intercourse by sucking out the male's bodily fluids. Enough said.
Garter Snakes: One Big Orgy
For the<a href="http://www.neatorama.com/2007/04/30/30-strangest-animal-mating-habits/" target="_hplink"> Red-Sided Garter Snake</a>, orgies aren't just a fantasy, they're very much a reality. But men, don't get too excited yet. According to Neatorama, it's the females who have sex with hundreds of partners during the mating season. The snake ladies release a pherome to attract the men and quickly a "mating ball" forms, which is, just as the name implies, a big ball of snakes trying to mate.
Porcupines: It's No Hazing Ritual
This <a href="http://science.discovery.com/top-ten/2009/mating-ritual/mating-ritual-02.html" target="_hplink">porcupine</a> mating ritual could easily be confused for a fraternity hazing ritual. But, according to Discovery Science, a male porcupine will shower a female with his urine before mating, and there's no keg stand involved.
Horseshoe Crabs: If You Like Long Walks On The Beach...
It's like an ad in the personal columns: "seeking mate for summertime romance on the beach under a full moon." Except that for <a href="http://www.wired.com/wiredscience/2009/02/animalcourting/" target="_hplink">horseshoe crabs</a>, this isn't romantic, it's just their regular mating ritual, WIRED reports. This anthropod only mates under these seemingly idyllic circumstances.
Elephants: Keeping Romance Alive
Who said chivalry was dead? The male <a href="http://www.wired.com/wiredscience/2009/02/animalcourting/" target="_hplink">elephant</a> takes his time to woo a female, courting her over a period of weeks before mating. While flowers and chocolate aren't included, the male does bring the female food and squirt her with water.
Mosquitoes: A Little Love Song
Who knew such an obnoxious insect could be so very romantic with its own species? <a href="http://www.wired.com/wiredscience/2009/02/animalcourting/" target="_hplink">Mosquitoes</a> flap their little wings, producing various sound frequencies (or to us, an annoying buzz). While the male normally produces a sound around 600 hertz, the female makes a 400 hertz sound. But compromise is key with these buggers. Both sexes are willing to adjust their sound level to create a harmonic match.
Snakes: Like A Magic Trick, Only Better
According to a BBC article, not only does a <a href="http://www.bbc.co.uk/dna/h2g2/A22547838" target="_hplink">snake</a> have <em>two</em> intromittent organs, but it also has the ability to turn its penis inside-out to better fit the female.
Dolphins: A Gay-Friendly Community
<a href="http://www.bbc.co.uk/dna/h2g2/A22547838" target="_hplink">Dolphins</a> are quite a progressive species. Not only are they considered one of the most intelligent animals, but according to h2g2, dolphins also engage in openly gay sex. Male dolphins have been known to practice various forms of intercourse with other males, experimenting with different holes.
Ducks: This Is Just Bad
Apparently some animal species don't find rape quite as abhorrent as we do. The male <a href="http://www.bbc.co.uk/dna/h2g2/A22547838" target="_hplink">duck</a>, also known as a drake, has a phallus so large that it can be the length of the drake himself, according to an h2g2 post. Due to his size, the drake can have sex with a female without her consent. It is not uncommon for a group of drakes to force a female to have sex, occasionally even drowning her. But the female duck has some defense mechanisms. She has the ability to store sperm in a side chamber and eject it if she is unsatisfied. It is thought that female ducks have evolved to create a complex genital passage due to the threat of unwanted sex.
Bowerbird: Not Just a Bachelor-pad
The male <a href="http://www.nileguide.com/blog/2010/03/10/the-most-ridiculous-animal-mating-rituals/" target="_hplink">bowerbird</a> doesn't settle for just any old bachelor-pad to woo his mate. Instead, NileGuide reports that he takes the time to decorate his nest, collecting feathers, flowers, berries, and shells to beautify his home and woo female Bowerbirds during mating season. The female Bowerbird chooses the nest that she likes best, and settles in with a male for the season. Perhaps men <em>should</em> spend a little more time decorating their apartments.
Cats: The Horror
It may sound like an erotic horror film, but a male <a href="http://www.bbc.co.uk/dna/h2g2/A22547838" target="_hplink">cat</a> has hook-like barbs on his penis, h2g2 reports. During intercourse, the penis cuts the female, encouraging her to ovulate.