Claire Asher

Nature

A crab spider’s guide to going airborne

Spiders can take to the skies by deploying special silk threads to catch the wind. But scientists have been stumped by how large spiders pull off this aerobatic feat, known as ballooning. Moonsung Cho at the Technical University of Berlin and his colleagues observed crab spiders (Xysticus spp.) weighing up to 25 milligrams, as the arachnids took flight in a park and a wind tunnel. The team found that the spiders raised one front leg into the air before extruding ballooning threads from organs...

news.mongabay.com

Hunting, fishing causing dramatic decline in Amazon river dolphins

Both species of Amazon river dolphin appear to be in deep decline, according to a recent study. Boto (Inia geoffrensis) populations fell by 94 percent and Tucuxi (Sotalia fluviatilis) numbers fell by 97 percent in the Mamirauá Reserve in Amazonas state, Brazil between 1994 and 2017, according to researchers.

Nature

DNA offers glimmer of hope for critically endangered rhino

The world’s last male northern white rhinoceros died in March, leaving two females as the sole survivors of their kind. But a genomic analysis shows that frozen rhino cells contain enough genetic diversity to help revive these great beasts.

Nature

The invasive snail that fooled zoologists

Conservationists have got the wrong snail on their list, according to a genetic analysis.
Takumi Saito at Tohoku University in Sendai, Japan, and his colleagues studied DNA from 66 freshwater limpets — a type of aquatic snail — collected in Japan, Hong Kong, Taiwan, Vietnam and Russia. On the basis of visible traits, each of the individuals was identified as belonging to one of three species considered native to Japan.

New Scientist

The curious fate of the eighth wonder of the world

In the early hours of 10 June 1886, the ground beneath Mount Tarawera on New Zealand’s North Island began to shake. After an intensifying swarm of earthquakes, the volcano erupted from three domes, spewing hot gases and rocks into the air. Surveyor Henry Roche observed the inferno from his camp nearby, describing “the striking spectacle of a dark, flat-topped mountain more than a mile long, red hot along its crest, and surmounted by a wall of fire 1500 feet high”.

Nature

Streams may skew carbon cycle as climate warms

Rising global temperatures could prompt some streams to release more carbon dioxide than they do now, exacerbating climate change. As their environment warms, algae and microbes living in streams photosynthesize faster and absorb more CO2 from the air. But they also grow faster, releasing extra CO2. To calculate the net impact of such changes, Chao Song at the University of Georgia in Athens and his colleagues monitored the temperature, dissolved oxygen lev...

Nature

Ants’ route-finding abilities put mapping software to shame

Faced with uneven terrain, ants often take the fastest, rather than the shortest, route to their destination.

Erik Frank and his colleagues at the University of Würzburg in Germany cleared paths through the grass around nests of a termite-eating ant (Megaponera analis) in Côte d’Ivoire. The ants could walk nearly twice as fast on the paths as on uncleared ground.
Individual scout ants leading raiding parties of several hundred worker ants...

Nature

Why dinosaurs arranged their eggs in a doughnut shape

Massive dinosaurs built specially designed nests to avoid crushing their eggs during incubation.

All modern birds with open-topped nests sit on them to keep the developing eggs warm. To find out whether egg-laying dinosaurs were able to do the same, Kohei Tanaka of Nagoya University Museum in Japan and his colleagues studied 40 clutches of fossilized eggs laid by oviraptorosaurs, a group of feathered dinosaurs that walked on two legs.
After analysing the eggshells’ structure, the authors conc...

Nature

Bats forgo sonar to fly under the radar

Some bats have a stealthy back up to their usual sonar system: barely detectable calls that might help the animals to evade adversaries.

Bats navigate at night by making calls and listening to the sounds that bounce back, a type of biological sonar known as echolocation. Aaron Corcoran at Wake Forest University in Winston-Salem, North Carolina, and Theodore Weller at the Pacific Southwest Research Station in Arcata, California, recorded the calls of hoary bats (Lasiurus cinereus) as the anima...

Nature

Unconventional lifestyle found in island bird

A flightless tropical bird has a social life previously seen only in human populations: brothers live together, share a mate and stay in touch with their parents. Jörn Theuerkauf and Roman Gula at the Polish Academy of Sciences in Warsaw and their colleagues used radio tracking to monitor populations of kagu (Rhynochetos jubatus) on the Pacific island of New Caledonia. They found that the birds breed in small groups belonging to larger family clans.

news.mongabay.com

Brazil’s actual forest-related CO2 emissions could blow by Paris pledge

Brazil is reporting its CO2 emissions within U.N. guidelines, but those rules ignore significant sources of national greenhouse gas emissions ¬by disregarding carbon emitting processes related to forests, say scientists. None of this underreporting is likely unique to Brazil, but it is perhaps more acute there than in other nations due to Brazil’s vast forests.
The U.N. doesn’t require Brazil and other developing nations to count certain greenhouse gas emissions in detail, especially sources ...

Nature

Early stick insect was a master of disguise

Stick insects had already evolved a striking resemblance to twigs by 99 million years ago.
Taiping Gao and Dong Ren at Capital Normal University in Beijing and their colleagues discovered a new species of stick insect (Elasmophasma stictum) in amber from Myanmar, which they dated to 99 million years ago.

Nature

Mass suicide documented in bacteria

Some bacteria trigger their own destruction by making their environment uninhabitable, a process that researchers have named ‘ecological suicide’. Many microbes produce by-products that alter the acidity of their environment, but large pH changes can cause their cells to burst.

Nature

Jays play nicely with the right hormone

Birds share more readily after being given the avian equivalent of oxytocin, a hormone linked with social bonding and maternal behaviour in mammals.

The hormone mesotocin boosts gregariousness in birds. To see what other powers it might have, Juan Duque and his colleagues at the University of Nebraska–Lincoln trained caged pinyon jays (Gymnorhinus cyanocephalus) to choose between sending a gift of a mealworm to a nearby jay or sending the treat to an empty cage.

Nature

Dexterous sea turtles use flippers as grippers

The flippers of sea turtles are superbly adapted for swimming, leading many scientists to assume that the flap-like appendages are not suited to other tasks. But Jessica Fujii at the Monterey Bay Aquarium in California and her colleagues have compiled evidence that turtles use their flippers to handle and eat prey.