To do their work, scientists have to be a lot of people: explorers, writers, educators, and in this case – Sherlock-rivaling investigators. While traversing the Peruvian rainforest on set for his show, TechKnow, science communicator Phil Torres came across something he’d never seen before: a colony of barklice moving together in almost perfect sync, like something out of boy band video.
A trained entomologist, Torres has spent more time in the Amazon’s alien terrain than most, so when the bizarre bug-dance caught his eye, he knew he was on to something that likely hadn’t been documented before.
“At first I couldn’t put a finger on why this six-legged dance looked so odd – until I realized that when one moved, so did the others, and when one paused, so did the others – but all in different directions,” he writes in a blog post.
“It’s a cohesive, start-and-stop movement that I haven’t seen before in any animal. I think I laughed a bit because [it] was so odd that it almost seemed ridiculous – why stop so much when you could just keep on moving? In the Amazon, sometimes all you can say is ‘wait- this is weird, right?'”
And it was. Really weird.
Now, before you spin into an uncontrollable bout of ‘nope’ we should probably mention that these tiny insects (order Psocoptera) are not the same kind of lice that ruin your life in grade school. They’re harmless – even to the trees they infest.
Footage in hand, and plagued by questions, Torres set off to unravel the movement mystery. How were these millimeter-long insects able to perfectly coordinate from inches away? Sounds easy enough, but imagine that you’re on a football field with 50 other people, 160 feet apart, running in opposite directions, and you have to match every single person’s start and stop time. And more importantly, why the hell were they doing it in the first place?
There seems to be evidence of some kind of rapid social transmission across the group that allows them to behave like a single entity (hivemind, anyone?). “My first guess for the ‘how?’ was that they could feel each other’s movements through the silk they live within; other animals like spiders are known to send messages through vibrations in silk so why not barklice too,” he says.
But as it often does, the internet threw a break in the ‘eureka!’ chain when during the investigation, Torres came across similar barklice behavior on YouTube – this time with no silk at all!
Several phone calls and stumped bug scientists later, it seemed no one would solve this puzzle. Torres even contacted Dr. Iain Couzin, arguably the world’s top expert in cohesive animal behavior.
“Couzin studies how animals coordinate their motion and make collective decisions regarding when, and where, to move … from swarming locusts to schooling fish and even human crowds,” explains Torres. “So if anyone were to have heard of a start-stop, mass movement like this, it would be [him]. But he hadn’t, and he was amazed.”
If the master of movement couldn’t solve the puzzle, there was just one more person to call: the master of barklice – yes, that is a thing – Illinois State University’s Dr Edward Mockford. Mockford has spent his entire career looking at the evolution of barklice specifically, and much to Torres’ excitement, came in for the win. He’d observed the RTS-style movement before, back in the ’50s, but was never able to record it, and admittedly hadn’t thought much about its function.
Torres, Couzin and Mockford will be working to analyze the ‘stops and starts,’ in the future and hope to crack the barklice code. Is there one individual leading the group? Or is it a cascading start, cascading stop? Or do they have some sort of internal timer or pulse coordinating them?
“One thing is for sure, this mystery doesn’t end here,” says Torres. “Especially with these scientists involved. It’s an exciting feeling to tell the story of a group of animals that doesn’t get a lot of attention, and hopefully captivate people with how many weird and amazing things are out there, waiting to be found.”