Sorry, Spidey: Geckos Are Size Limit for Climbing Walls
If you have hopes of replicating Spiderman's ability to climb walls, a new study may crush your dreams.
If you have hopes of replicating Spiderman's ability to climb walls, a new study may crush your dreams.
According to the paper, released today in the journal Proceedings of the National Academy of Sciences, an adult human would need to have adhesive pads covering about 80 per cent of their front to stick to a wall.
Alternatively if a human followed the gecko's lead and relied on adhesive pads on their feet for sticking power, their foot would need to be about one metre long and about 40 centimetres wide.
"While that is good news for shoe industry, it's not so great for Spiderman as he can't run after villains with such big feet," said co-author Dr Christofe Clemente, from the University of the Sunshine Coast.
The comic book-inspired findings emerged from the more serious study looking at "sticky" animals in the hope of developing effective bio-adhesives.
For the study, Dr Clemente and his colleagues at the University of Cambridge's Department of Zoology examined 225 species of climbing animals ranging in size from the smallest mites to the largest geckos.
They found the percentage of an animal's body surface covered by adhesive footpads increased across species as the animal's weight increased.
For a mite just 0.02 per cent of its body was adhesive pads. Spiders needed about 0.92 per cent coverage to stick to a surface, while 4.3 per cent of the gecko's body surface was adhesive footpads.
"If your childhood dream is to become Spiderman, you are going to have to follow this pattern," Dr Clemente said.
"Essentially from your toes to the top of your chest will have to be sticky pad.
"This isn't going to work, if you go to hug someone it's going to be a real mess."
Dr Clemente said the study suggested the size limit to sticky footpads as an evolutionary solution to climbing was around those of a gecko.
Besides developing larger sticky surface areas, animals also could make their adhesive footpads stickier.
However this also had its limits as the animals needed to be able to unstick their feet.
Within species, the pads' adhesive strength increased for larger animals, but there was no evidence that the heaviest climbers had the strongest sticking power.
Dr Clemente said there was lively debate in the community about which was the "stickiest" animal.
He was most impressed by the Asian weaver ant, which could hold 500 times its body weight upside down on a smooth surface.
"That's like you holding a truck while clinging on to a glass ceiling with nothing but these adhesive pads [to keep you there] so that is really quite impressive," he said.
Dr Clemente said the study had implications for the development of man-made bio-inspired adhesives.
At present bio-inspired adhesives are only effective on small areas.
"Animals are constrained by this evolutionary process, but in manufacturing we don't have that constraint so we can find ways we can scale up these adhesives to do better than evolution has," he said.
That, he added, should give a glimmer of hope to those children who still wanted to emulate Spiderman.
A total of 139 new species were discovered in 2014 in the Greater Mekong Region (Cambodia, Laos, Myanmar, Thailand and Vietnam), according to a report released this week. The newly found collection includes 90 plants, 23 reptiles, 16 amphibians, 9 fish and 1 mammal, according to the authors at the World Wildlife Fund (WWF). The lone mammal is this long-fanged bat
, whose teeth were "very conspicuous even for the first sight," said Tamas Gorfol, one of the researchers who named the new species. The teeth help the bat, which hails from three locations in Vietnam, to chomp into hard-shelled prey, such as large shelled insects. Tom Gray, Manager of Species Conservation for WWF-Greater Mekong, told Discovery News that more bat species will likely be named soon, since other researchers are now analyzing bat finds that take a while to review. "There is a chance some of these bats could go extinct even as they are being named," Gray said. "Southeast Asian landscapes are changing dramatically due to rapid development, leaving fewer and fewer refuges for bats."
At 21.3 inches long, this new giant stick bug is the second longest insect ever found. In first place is another stick insect that's 22.3 inches long. It lives in Borneo. Jerome Constant, who led the expedition to discover Phryganistria heusii yentuensis, explained, "Three of the biggest insects have just been described last year. There are more for sure!" This female stick insect was found hanging out at night near villages and rice fields in the small Vietnamese town of Tam Dao.
Two new species of orchids were discovered during market surveys assessing illegal trade in wild ornamental plants. Researcher Jacob Phelps nearly didn't publish the new finds, as he was concerned that attention could mean the orchids' doom. "When the targeted species are narrowly distributed or only occur in small populations, the conservation effects can be sudden and dramatic," he explained. Still, holding back the information would not be ethical. Lack of attention also carries its own risks. Biologist Jodi Rowley, a member of the IUCN Amphibian Red List Authority, explained, "Put simply, it's very hard to conserve something we don't know exists. "Once a species is known to science, it is typically much easier to direct conservation resources towards it, if needed."
Two of Rowley's students took photographs of an unusual frog that they spotted. The frog appeared to be covered in sandpaper. "As soon as I saw the spikes on the back of the male, I knew it was something different to any frog I'd seen before," said Rowley, who later referred to the spikes as "thorns." The adult frogs are a distinctive combination of pink and yellow, at least at night. During the day, their yellow backs fade to a duller brownish hue. Why and how the frog changes color is unclear, although the change itself is not uncommon. "Many frog species can change color depending on time of day, temperature, or even mood," Rowley said. As for the sandpapery appendages on the frog's back, the researchers determined that these are small conical "thorns." The scientists believe that because only males have these, they could play a role in mate recognition. The thornier a male is, they suspect, the more attractive he is to a female.
A wasp that steals its prey's free will with a single sting before eating it alive sounds like a monster straight out of a storybook. Visitors to the Berlin natural history museum Museum für Naturkunde certainly thought so, voting to name this wasp
, after the soul-sucking dementors from the Harry Potter series.
Michael Ohl, who studied the wasp, explained that A. dementor
hunts cockroaches by injecting a venom into them that turns the roaches into passive zombies. Once a cockroach victim has lost control, the wasp drags its stupefied prey by the antennae to a safe shelter to devour it.
This wolf snake is so well camouflaged that it escaped discovery until recently, when it was found at the Phnom Samkos Wildlife Sanctuary in Cambodia. "There is no other species of wolf snake that looks like this," said Thy Neang, the leader of the field survey that discovered the snake. Like all wolf snakes, it has large but non-venomous teeth in both jaws, which it uses to hunt small lizards and frogs at night. Its distinctive coloring helps it to blend in with the tree bark and mosses of its mountain forest home.
This new genus and species of moth was named in honor of Princess Maha Chakri Sirindhorn of Thailand, who supports the Chaipattana Foundation. The foundation owns the forest where the moth was found. These tiny moths form an important part of the base of the food web, converting plant matter into animal protein and serving as food for many animals.
The "feathers" on this coral discovered near Thailand's Phuket Island are actually soft tentacles. Previously, members of its genus were only known from the Red Sea and the western Indian Ocean. "We are now seeing more emphasis on coral reef research and education, including taxonomy, at the government and university level occurring in Thailand, as well as Cambodia and Vietnam," remarked Michael Janes, leader of the team that discovered the coral. "
shows great promise for the future of coral reefs in the region."
The newly named crocodile newt lurks in and around the ponds of Taunggyi, which is the capital of Shan State, Myanmar. People in the region have noticed this tiny croc-resembling newt for years, but it was only recently that scientists took note and closely examined it. Genetic analysis determined that it is a new species. Although just named, the newt is already under threat. Construction at the nearby Taunggyi Unviersity could cut off the water flow to the newt's only known breeding pond, which may result in the aquatic amphibian's extinction, according to information provided by WWF. Gray said many newts are struggling due to their close co-habitation with humans. Their preferred shady hiding places are disappearing with urbanization, and many are killed by traffic during season migrations to and from breeding ponds, which are increasingly clogged with litter.
This bent-toed gecko has a claim to fame beyond its distinctive toes. It's the 10,000th reptile known to science. An astonishing 16 bent-toed gecko species were discovered in the Greater Mekong region in 2014 along, bringing the total number of bent-toed geckos species to 197. This in itself is noteworthy because no other gecko genus contains more than 15 species in total. According to WWF, the future of this gecko and the other species in the Greater Mekong depend on protection from poachers, conservation of their habitat, maintenance of free-flowing rivers, smart infrastructure development and much more. Gray said, "There is no one single solution, but most importantly, governments, businesses and citizens need to commit to the growth of a green economy in the Greater Mekong. This involves developing the economy sustainably, prioritizing thriving natural ecosystems at all levels of decision making so that people and wildlife can enjoy their benefits for generations to come." The governments of the Greater Mekong have all pledged their support to "the development of a green, inclusive, and balanced economy" to reduce poverty, biodiversity loss and greenhouse-gas emissions.