Valentine's Day Double Feature

Originally published February 10, 2010 (The Manitoban, Vol. 97, No. 21)

Kissing Bugs

Rhodnius prolixus is one of several species of blood sucking insects belonging to the order hemiptera that can be found from southern Mexico to northern South America. With strong jaws, a powerful bite, and sucking mouthparts specialized for drinking blood, this fiend also produces and secretes proteins into the wounds it makes that function to increase blood flow to the wound site. This allows the animal to get more blood more quickly (kind of like pulling up at a drive-thru and ordering extra-large...or maybe it's more like holding up the drive-thru). 

"So the jerks drink blood, but why call them kissing bugs", you want to know. The clever little devils get the name because they often bite humans and other victims such as cats, dogs, rats, and other hapless mammals on the lips or face (and while they're sleeping to boot). However, unlike your typical fantasy Romeo (or Juliet, or Prince Charming, or Ted Bundy, or whoever), these six-legged freaks also defecate as they kiss (bite). The wound swells, becoming itchy and irritated, and what do you do? Exactly what you shouldn't you fool, which is to scratch the damn thing and rub poop all into your love-bite. Aside from being totally gross (and this is really important, especially if you are planning a budget South American holiday this "spring break"/"reading week") these kissing bugs are discourteous enough to leave you with a little surprise in their fecal matter that goes by the name of Trypanosoma cruzi, perhaps better known as Chagas disease or American sleeping sickness. 

Once infected with this flagellated¹ protozoan parasitic disease you might at first notice only swelling around the wounded area, perhaps a bit of fever--in short, nothing much to write home or see a doctor about. Yet things get sinister once chronic symptoms start to develop: malformation and inflammation of the intestines and heart, and damage to the nervous system occur. There is not yet an effective cure for Chagas disease but there are also educational programs and vector control measures (i.e. spaying insecticides) in place where Chagas disease is common.

R. prolixus gets a pretty bad rap overall, what with killing thousands of humans each year and causing much pain and suffering, but there is something to be admired in an animal so stealthy and ingenious as this one. At least, this writer thinks so. 

If you are planning a holiday this winter, keep in mind that a date with Rhodnius is kind of like having unprotected sex with a stranger folks; there's no telling how much trouble you might get into--so pull down your mosquito net, buckle your pants up extra tight, and watch out for that bad old Rhodnius this Valentine's day!

¹ A flagellum is kind of like a tail.

Venus Flower Basket

The stunningly beautiful venus flower basket is nothing like a kissing bug. The venus flower basket, Euplectella aspergillum, is a type of glass sponge that lives anchored to the sediments in deep ocean waters anywhere from 40 to 5,000 metres deep in the tropics of the South Pacific. It belongs to the class of sponges called Hexactinellida because its skeleton is made of long filaments of silica called spicules that have a six-pointed radial geometry. 

The fine silica fibres produced by Euplectella are of particular interest for fibre optics research because of their ability to transmit light in a similar (but superior) fashion to that used in modern telecommunications fibre optics. Commercial fibre optics require manufacturing under high temperatures but because the glass sponges create fibres under lower temperature they contain ions such as sodium that enhance their fibre optic properties, something we humans haven't yet figured out how to do. The fibres of the sponges are stronger than those used in modern fibre optics as well. The construction of the sponge is also of interest because of the unique arrangement of the fibres, which are laid down in concentric horizontal, vertical, and diagonal layers of varying thickness (from nanometres to centimetres). The result is an incredibly strong but delicate frame that is highly resistant to cracks and breaks. 

Fibre optics might only romantic in the form of those flashy Valentine's cards and construction workers might be sexy to some, but I'll bet their bosses (the ones who nerd about on computers and in labs with sponges looking for stronger ways to erect office buildings) aren't, so why are you reading a Valentine's special on Venus flower baskets and what am I talking about? Shrimp. And I don't mean those cheap rings you get from Safeway.

While Euplectella is busy growing up into a strapping young adult sponge, a young pair of shrimp belonging to the family Spongicolidae sometimes move into the base of Euplectella's cone as it grows. The shrimp graze on particulate food matter that the sponge wafts in through it's flagellated (there's that word again) water chambers, do a bit of cleaning, and generally just loaf about, happily in love. Euplectella keeps growing, and eventually a covering or cap is formed at the top of the cone, trapping the shrimp within the sponge. 

Nonplussed, the happy couple proceed to mate and release their young larvae, which are small enough to fit between the latticework of the sponge, out into the great blue deeps. A mated shrimp pair thus spends their entire life within the sponge and for this reason, Venus flower basket carcasses were traditionally given as wedding presents in Japan and the Philipines, to symbolize either eternal love, eternal imprisonment, or both!