Canadian scientist thrills the web by live-tweeting spider sex

The detailed play-by-play of a black widow mating session in Toronto makes spiders seem more sweet than spooky.

Play-by-play of a black widow mating session in Toronto makes spiders seem more sweet than spooky

Catherine Scott, left, a PhD student in the Andrade lab at the University of Toronto Scarborough, captured the web's attention with tweets about what goes on in the webs of spiders she studies. (Sean McCann/

Like nurses, black cats, and pretty much every cultural group on Earth, spiders are often misrepresented by their depictions around Halloween.

Anything is spooky when it's the size of a minivan and has an apparent thirst for human blood — but real spiders can't grow much larger than 28 centimetres, and they certainly don't want to attack you.

And as an illuminating series of tweets from a University of Toronto PhD candidate show, spiders may actually have more in common with the Halloween revellers awkwardly trying to hook up after a party than they do with any decorations outside.

Catherine Scott studies courtship behaviour and sexual communication in black widow spiders, with a special interest in how pheromones on spiders' silk are involved in attraction.

Clearly passionate about her work, Scott tweets about spiders constantly. Her feed is a veritable wealth of photos, facts and stories about the eight-legged animals, as well as a source of information for those who "might not yet be aware what fascinating creatures they are."

Friday was a day like many others for the PhD student as she conducted mating trials with a species of black widow (Latrodectus hesperus) in the Andrade lab at U of T's Scarborough campus.

She put three male spiders and three females into a "mating arena," and then sat back to wait for the elaborate courtship displays to begin.

This, as her followers soon learned, can take quite some time.

"Since I was waiting around hoping to catch the spiders in the act, I thought I would tweet a bit," Scott told CBC News on Monday. "I guess the weird and wonderful behaviour of black widows that originally got me hooked was also intriguing to folks following along."

It certainly was, judging by the amount of replies, retweets, favourites and follows that came her way that afternoon (and later, when Gizmodo spotlighted her now viral tweets.)

By the time Scott called it a night, about four hours after she started documenting the mating session and six after it started, spider lovers and casually interested observers alike were on the edge of their seats with anticipation.

"Maybe some nice lite jazz, soft lighting and a nice Chianti would help?" suggested one follower after Scott lamented that the spiders were "taking their time."

"Oh we've got super sexy red lighting up in here," she replied. "And the romantic buzz of the laboratory air circulation."

And their excitement grew with every update Scott provided about the spiders' behaviour.

As Scott's tweets continued, it became clear that spider mating sessions are a lot more complicated — and entertaining — than most people know.

During lulls in the action, the scientist used her platform to further educate Twitter about everything from how black widows transfer sperm and  what their copulatory organs look like to whether or not they actually participate in sexual cannibalism (rarely, she says.)

While Scott says she's "a bit bewildered by the attention, to be honest," the fact that people were so interested in her tweets that afternoon makes sense. 

"I fell in love with spiders because of their fascinating courtship behaviour and sophisticated communication systems," she told CBC News. "Males perform elaborate courtship displays for the female, dancing and singing to get her attention and convince her to mate. If you've never seen the YouTube videos of male peacock spiders dancing, I highly recommend checking them out!"

And dancing isn't the only thing males do to impress potential mates.

"In some species male spiders give gifts to females," she said. "But the gift is a dead insect wrapped in silk, and he brings it because if she's eating the gift she's less likely to eat him, and he'll be able to copulate longer than without a gift."

Sadly for those following the saga of Scott's spiders, none of her subjects were successful in their attempts to mate on Friday. 

"As riveting as these last 5.5 hours have been, I have to go home and eat dinner," she tweeted around 5:30 p.m. ET. "I've set the cameras to continue recording in my absence. I'll check back tomorrow morning and look at the video. So sometime, in the near future, you can tune back in for some live-tweeting of the video watching. Advantage: fast-forward!!!!"

On Monday, Scott reported what she'd seen while watching the video — and the news was anti-climactic for some.

"BTW I was able to go through the video from those mating trials this morning and as far as I can tell not a single mating occurred. ::::(" she tweeted.

All's well that ends well, though. The spiders will likely get to try again in the future, and when they do, Scott's new followers will be more educated about what's going on than they were the first time.

"This month, for #Arachtober, my partner Sean and I have been tweeting about a different spider family every day to highlight their beauty and amazing diversity," she said. "Friday afternoon's tweets weren't directly related to Arachtober... Mostly I was just bored. Tweeting my observations and seeing people's responses helped to remind me why I love black widows and their behaviour so much, though!"