Researchers have long been fascinated with ant rafts. These floating mats form during rain storms and floods and are composed of thousands of individual insects.
Scientists have found that the living rafts possess their own unique material properties, displaying buoyancy and behaving, alternately, like a solid and like a liquid.
How the ants manage to create such engineering masterpieces, however, has remained largely unknown.
Now, researchers have discovered one architectural secret behind the ant rafts. The ants, it turns out, cling to one another using all six of their legs—a single ant can have up to 20 of its comrades’ legs grabbing its body.
The Georgia Institute of Technology researchers found that 99 percent of ant legs are gripping another ant, meaning “there’s no free loaders” when it comes to hitching a ride on the rafts, they said in a statement.
Scientists didn’t discover this trick earlier because it’s exceedingly difficult to look inside those dense balls of insects.
To get around this problem, the team first created a number of ant rafts by swirling 110 insects in a beaker full of water. After the rafts formed, the researchers froze them with liquid nitrogen and used super glue to ensure the ants stayed in place.
CT scans allowed the researchers to examine how the rafts’ individual components were related.
Ed Yong elaborates on the findings for National Geographic:
They don’t just stick their pads to the nearest thing they can find; they typically attach to their neighbours legs and feet, rather than their bodies.
These connections allow the ants to change the shape of their structures by bending or stretching their legs. That explains why the structures are so elastic, and why they can absorb incoming forces more effectively.
The foot-to-foot connections also suggest that the ants actively control the nature of their balls. The team found other such clues. For example, a ball of living ants is less densely packed than a ball of dead ones, implying that they are actively pushing their neighbours away.
This presumably helps to create the air pockets that keep the rafts afloat.
While constructing the rafts does not involve intelligence, the team told Yong, the nature of those balls does turn out to be much more complex than scientists expected.
The viceroy butterfly appears similar in colour and pattern, but is markedly smaller and has an extra black stripe across the hind wing.
The eastern North American monarch population is notable for its annual southward late-summer/autumn migration from the United States and southern Canada to Mexico.
During the fall migration, it covers thousands of miles, with a corresponding multi-generational return North.
The western North American population of monarchs west of the Rocky Mountains most often migrate to sites in California but have been found in overwintering Mexico sites Monarchs were transported to the International Space Station and were bred there.
The giraffe weevil (Trachelophorus giraffa) is a weevil endemic to Madagascar. It derives its name from an extended neck much like that of the common giraffe.
The Giraffe Weevil is an herbivore and is not commonly known by most people. The giraffe weevil is sexually dimorphic, with the neck of the male typically being 2 to 3 times the length of that of the female.
Most of the body is black with distinctive red elytra covering the flying wings. The total body length of the males is just under an inch (2.5 cm), among the longest for any Attelabid species.
The extended neck is an adaptation that assists in nest building and fighting.
When it comes time to breed, the mother-to-be will roll and secure a leaf of the host plant, Dichaetanthera cordifolia and Dichaetanthera arborea (a small tree in the family Melastomataceae), and then lay a single egg within the tube.
She will then snip the roll from the remaining leaf in preparation of the egg hatching.
Piotr Naskrecki was taking a nighttime walk in a rainforest in Guyana, when he heard rustling as if something were creeping underfoot.
When he turned on his flashlight, he expected to see a small mammal, such as a possum or a rat.
“When I turned on the light, I couldn’t quite understand what I was seeing,” said Naskrecki, an entomologist and photographer at Harvard University’s Museum of Comparative Zoology.
A moment later, he realized he was looking not at a brown, furry mammal, but an enormous, puppy-size spider.
Known as the South American Goliath birdeater (Theraphosa blondi), the colossal arachnid is the world’s largest spider, according to Guinness World Records.
Its leg span can reach up to a foot (30 centimeters), or about the size of “a child’s forearm,” with a body the size of “a large fist,” Naskrecki told Live Science.
And the spider can weigh more than 6 oz. (170 grams) — about as much as a young puppy, the scientist wrote on his blog. [See Photos of the Goliath Birdeater Spider]
Some sources say the giant huntsman spider, which has a larger leg span, is bigger than the birdeater.
But the huntsman is much more delicate than the hefty birdeater — comparing the two would be “like comparing a giraffe to an elephant,” Naskrecki said.
The birdeater’s enormous size is evident from the sounds it makes. “Its feet have hardened tips and claws that produce a very distinct, clicking sound, not unlike that of a horse’s hooves hitting the ground,” he wrote, but “not as loud.”