Not your average Valentine’s Day

February 13, 2018 | Science

Three tales of science and sex


Whether or not you’ve been pierced by Cupid’s arrow this Valentine’s Day, we think this scientific look at seduction will capture your curiosity, if not your heart.

Faculty from MacEwan’s biology, psychology and anthropology departments are studying the role sex has in helping us better understand insects, amphibians, and ultimately ourselves.


Insect sex traps

Carefully crafted forest traps, biosurveillance and sex might sound like the premise for a Bond film, but Dr. Leah Flaherty, an assistant professor in MacEwan’s biology department, is spying on invasive beetles, not bad guys. And her espionage has serious implications.

In a project primarily funded by the Canadian Food Inspection Agency, Leah uses pheromones, the scent that attracts mates, to lure and trap bark and wood-boring beetles. Part of Leah’s research evaluates what blend of pheromones will attract the greatest diversity of species.

“These insects could have devastating consequences,” explains Leah. “An invasion by the Emerald Ash Borer could potentially eliminate ash trees in North America, and many of Edmonton’s street trees are from this genus. They could all be destroyed.”

The beetle pheromones are synthetically created by chemists, and placed in packets on traps hung from trees. The insects are attracted to the smell, hit the trap and fall into a “killing cup,” where they drown in salt water.

“They think they’re going to get lucky, when in fact they’re just going to die,” says Leah.

Bark and wood-boring beetles are particularly troublesome because they can hide in wood packaging material used in international trade, and travel easily from country to country. Leah’s research is preventative, with the goal of trapping a range of invasive species early on, when it’s easier and less expensive to eradicate or manage them.


Mysterious mating calls

Another MacEwan faculty member, Dr. Shannon Digweed, spent time capturing creatures – but to study them, not eradicate them. Shannon is an assistant professor in psychology and biology, and her curiosity was piqued by the loud call of Edmonton’s wood frogs.

Wood frogs are a local species that hibernate over winter, but emerge at the first sign of thaw with one thing in mind – finding a mate. The males congregate in shallow water, and start their mating calls in the hopes of attracting females for their once-a-year chance to produce offspring.

“They’re called ‘explosive breeders,’ because of their really short, 48-hour breeding window,” explains Shannon. “The calls start late at night and ramp up really quickly. At first there’s four or five males, and suddenly there are hundreds of them calling and breeding.”

Shannon and a now-graduated psychology honours student, Nicholas Rehberg-Besler, decided to find out if the pitch of the calls had any correlation to the size and desirability of the males.

The team of two captured 30 frogs from Edmonton’s river valley, and recorded their body size and calls, which sound similar to a duck’s quack. While it turns out there’s no connection between the pitch of the call and physical quality of the male, there was still a useful lesson to be learned, says Shannon – adding that humans are known for making similar assumptions about our own species.

“There’s this whole idea of the ‘DJ effect.’ DJs tend to have lower pitched voices, so you hear a DJ on the radio, and it evokes this image of a tall, big guy,” says Shannon. “When you see that guy in person, it can be surprising if he’s small or below average height.”

Even though the notion that bigger body size directly relates to lower-pitched voice isn’t accurate, the researchers did find that each wood frog mating call was unique.

“Each wood frog has their own voice, which is something you typically find in mammals, not amphibians,” says Shannon. “The next step would be to find out if females are responding to those individual calls in some way, like finding their mate from the previous year.”


R-rated artifacts

The Department of Biology doesn't have the monopoly on sex-related research. Dr. Katie Biittner, a lab instructor in the anthropology department, finds students are often shocked when her class slides include a photo of an ancient piece of pottery with pornographic images. But maybe they shouldn’t be.

Living in a sexualized, 21st century culture, we have default ideas about the past based on our modern worldview, explains Katie. “These may be really explicit sexual acts on these artifacts, but was it meant to be read as sexual by that culture?”

Katie often uses Moche erotic pottery as an example of how modern scholars misinterpret ancient artifacts. The Moche civilization ruled northern Peru from about AD 100 to 700, and left behind many pots with graphic sexual imagery.

This type of pottery was found in royal or elite households, Katie explains, and was only used for feasting or large, public displays of consumption. Within this context, the pots can be understood as more than a sultry piece of art.

“One of my favourite interpretations is that these images are a graphic indicator of the power dynamic in that society,” says Katie. “A lot of the acts on the pots show submission and dominance. It suggests that the elite, wealthy individuals were showing off their power. It makes a lot of sense.”

As an archaeologist, Katie says it's incredibly important to check your bias when you find yourself shocked by something you perceive as sexual. “We do a grave injustice to the people who came before us if we only interpret the past using our own cultural lenses.”

For example, in our culture, sex sells. Breasts are often considered acceptable as part of a lingerie ad campaign, but controversial in the context of nursing mothers. Katie says recognizing personal bias doesn’t just help you understand the past, but allows you to question current social constructs.

“Studying artifacts doesn’t always tell us a lot about people in the past. It often tells us more about ourselves, and how we can do better and be better.”


While your Valentine’s Day gifts are more likely to be chocolates and paper hearts than beetles, frogs and ancient pottery, we think the work MacEwan faculty are doing to protect our environment, understand verbal communication and break down biases is well-worth celebrating.

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