An Alberta researcher has discovered seven new species of beetle by poking around in dead wood.
University of Alberta master’s student Charlene Wood revealed this week that she had discovered seven new species of beetle in northwestern Alberta by studying dead aspen trees.
Deadwood houses thousands of species, Wood said, but has received little attention from scientists.
As part of her conservation biology degree, Wood chose to study beetles in a forest about 170 kilometres north of Grande Prairie during 2007 and 2008. “Beetles are one of the most species-diverse animals known,” she said, with about a million varieties thought to exist – only 350,000 of which have been identified.
Wood said she wrapped dead and dying aspen trees in a mesh to funnel all the bugs in them into collection jars. She then spent about two years sorting through the bugs she caught, picking out all the beetles and identifying them under a microscope.
In late 2009, Wood said she found one beetle that didn’t match anything in her reference books. A beetle expert in Germany confirmed that it was likely a new species. She went on to find six other new species.
Six of the new bugs are “minute brown scavenger beetles” – flat brown or black bugs that are about two millimetres long and eat fungi found on decaying vegetation. “They look super similar from the outside,” Wood said, and can only be told apart through dissection.
The seventh was a monotomid beetle that’s reddish-brown, three millimetres long and equipped with round clubs on its antennae. “It was one of my most commonly collected beetles, so we know it’s not a rare species.” This one appears to hang out in tunnels created by bark beetles.
These new bugs help break down dead wood in the forest, Wood said, and probably aren’t a threat to living trees.
This research helps us better understand biodiversity in Alberta, said John Spence, a professor of forest entomology at the University of Alberta and Wood’s supervisor.
“The fact that right under our noses there are still treasures like this for science to discover is quite amazing,” he said. “It wouldn’t surprise me if some of these small species may actually occur in St. Albert, but just haven’t been found yet.”
Wood is now working to formally name and document these new species.
A Swedish researcher has given dung beetles little green boots to show how they keep cool using balls of poop.
Swedish behavioural neuroscientist Jochen Smolka published a paper in Current Biology this week explaining how dung beetles stand atop dung balls to cool their feet.
“What we’re interested in is finding out how animals use their vision systems to navigate,” said Smolka, who works at Sweden’s Lund University. His team studies dung beetles due to their simple navigational patterns.
Dung beetles eat the plant matter and bacteria found in dung, he explained. When they find a pile, they gather some of it into a ball, roll it away in a straight line with their back legs, stop and chow down.
Researchers knew that the beetles would sometimes stand on their balls and spin around — a sort of dance that helps them figure out where they’re going. Smolka’s team noticed that the bugs did this far more often at noon than at other times, leading them to suspect a link to heat.
The team studied wild dung beetles in South Africa by placing them in three-metre wide arenas. Both had dung piles in their middles, but one was shaded so that it was about 10 degrees cooler than the other.
When the arenas were below 50 C, the team found that the beetles always motored out of the rings in a straight line without stopping. When it was hotter, they would periodically stop, climb on their balls, preen their feet (possibly spitting on them), do a little dance and carry on. They were seven times more likely to do this in the hotter ring than the colder one.
Infrared cameras revealed a possible cause. “Within a few seconds of being on the ground,” Smolka said, “the (front) legs heat up by about 10 degrees.” Beetle brains start cooking at about 40 C, so this temperature spike is hazardous to their health. When the bugs climbed on their balls, their legs cooled down about seven degrees. Could they be using the balls to cool off?
To test this, the team gave the beetles insulated boots in the form of dabs of green dental silicone on their front legs and put them in the hot ring. The beetles were about 35 per cent less likely to climb on their balls during their trips once they had boots on. Further tests showed that the balls themselves were much cooler than the ground or beetles due to evaporation, and slightly cooled the ground that the bugs stepped on.
This suggests that dung beetles use their balls as thermal refuges, Smolka said, similar to how ants escape the heat by climbing up on sticks. “The beetle doesn’t have to get up on a stick because they already have their own air-conditioned platform with them.”
