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Sun, 05 Dec 2021
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Butterfly

Sexy or repulsive? Butterfly wings can be both to mates and predators

butterflies
© William Piel
Oliver found that the eyespots of some butterflies, such as this pair of mating Bicyclus anynana, serve to both
Butterflies seem able to both attract mates and ward off predators using different sides of their wings, according to new research by Yale University biologists.

Trying to find the balance between these two crucial behaviors is one of nature's oldest dilemmas, according to Jeffrey Oliver, a postdoctoral associate in Yale's Department of Ecology and Evolutionary Biology and lead author on the study, which appears online today in the journal Proceedings of the Royal Society B: Biological Sciences.

"You want to be noticeable and desirable for mates, but other onlookers, including predators, are paying attention to those signals as well."

Oliver was interested in whether the eyespots on the upperside of butterflies' wings - specifically, those of bush brown butterflies - serve a different purpose than the ones on the underside. Ever since Darwin's time, biologists (including Darwin himself) have postulated whether the upperside patterns could be used to attract mates, while at the same time, those on the underside could help avoid predators.

Fish

Scripps Scientists Help Decode Mysterious Green Glow of the Sea

green bioluminesence
© unknown
Experiments by Dimitri Deheyn and Michael Latz revealed green bioluminescence.
Dual purpose discovered for worm's brilliant bioluminescent light

Many longtime sailors have been mesmerized by the dazzling displays of green light often seen below the ocean surface in tropical seas. Now researchers at Scripps Institution of Oceanography at UC San Diego have uncovered key clues about the bioluminescent worms that produce the green glow and the biological mechanisms behind their light production.

Marine fireworms use bioluminescence to attract suitors in an undersea mating ritual. Research conducted by Scripps marine biologists Dimitri Deheyn and Michael Latz reveals that the worms also may use the light as a defensive measure. The report, published as the cover story of the current issue of the journal Invertebrate Biology, provides insights into the function of fireworm bioluminescence and moves scientists closer to identifying the molecular basis of the light.

"This is another step toward understanding the biology of the bioluminescence in fireworms, and it also brings us closer to isolating the protein that produces the light," said Deheyn, a scientist in the Marine Biology Research Division at Scripps. "If we understand how it is possible to keep light so stable for such a long time, it would provide opportunities to use that protein or reaction in biomedical, bioengineering and other fields-the same way other proteins have been used."

Better Earth

Alaska's Mount Redoubt has another large eruption

The Mount Redoubt volcano had another large eruption Saturday after being relatively quiet for nearly a week.

Radar indicated a plume of volcanic ash rose 50,000 feet into the sky, making it one of the largest eruptions since the volcano became active on March 22, said the National Weather Service.

The ash cloud was drifting toward the southeast and there were reports of the fine, gritty ash falling in towns on the Kenai Peninsula.

Magnify

Birds Can 'Read' Human Gaze

jackdaw
© iStockphoto/Dmitry Maslov
We all know that people sometimes change their behavior when someone is looking their way. Jackdaws --- birds related to crows and ravens with eyes that appear similar to human eyes --- can do the same.
"Jackdaws seem to recognize the eye's role in visual perception, or at the very least they are extremely sensitive to the way that human eyes are oriented," said Auguste von Bayern, formerly of the University of Cambridge and now at the University of Oxford.

When presented with a preferred food, hand-raised jackdaws took significantly longer to retrieve the reward when a person was directing his eyes towards the food than when he was looking away, according to the research team led by Nathan Emery of the University of Cambridge and Queen Mary University of London. The birds hesitated only when the person in question was unfamiliar and thus potentially threatening.

In addition, the birds were able to interpret human communicative gestures, such as gaze alternation and pointing, to help them find hidden food, they found. The birds were unsuccessful in using static cues, including eye gaze or head orientation, in that context.

Bizarro Earth

Urban hunters do most harm to ape populations

Image
© WSPA/K. Ammann/Rex Features
Ape parts discovered in markets tell little of how the populations are faring.
Commercial hunters from towns are exacting a much bigger toll on great apes than subsistence hunters from small villages, according to an analysis of ape nest density near human settlements.

The finding that numbers of gorillas and chimpanzees appear to have dwindled twice as much near towns in Gabon than near villages supports a focus on conservation efforts that tackle commercial hunting over those that aim to convince villagers to give up subsistence hunting, says Hjalmar Kühl at the Max-Planck-Institute for Evolutionary Anthropology in Leipzig, Germany, who conducted the study with colleagues.

The team counted sleeping nests left by gorillas and chimps in Gabon's mountainous Moukalaba Doudou National Park. They found that nest density decreased the closer they got to the towns that surround the park. The towns' populations range from 10,000 to 18,000 people.

Although some nests could be found close to the towns, their overall density was only half that seen in the centre of the park. In contrast, the team found no such gradient near smaller villages.

Frog

UK: Public asked to take part in largest ever survey of garden amphibians and reptiles

Frog
© Getty
Frogs spend time in garden ponds when hibernating or breeding
Frogs, newts and other "pond life" found at the bottom of the garden are to be counted in the first UK survey of reptiles and amphibians.

Hundreds of frogs, toads, snakes and lizards can live at the bottom of town and country gardens.

However global warming and development means many species are increasingly at risk. Of the 13 species of amphibians and reptiles native to the UK, 10 are considered endangered including the great crested newt, natterjack toad, adder and pool frog. Other species like grass snakes or common frogs are also suffering from habitat loss.

The national "stock take" of newts, toads, snakes and other traditional "garden pests" has been organised by a network of conservation groups including the British Trust for Ornithology and Froglife.

Black Cat

Kenyan lions being poisoned by pesticides

Kenyan lions
© Getty
Kenya's lion population is a fifth of what it was in the 1970s
Conservationists call for ban after 'staggering' number of deaths

Conservationists in Kenya are calling for a deadly pesticide to be banned after it was linked to the poisoning of a "staggering" number of lions and other wildlife.

The East African nation famous for its immense game reserves is also home to traditional cattle herders whose livestock often comes under threat from predators such as lions and hyenas. In the past, this has seen lions shot or speared but more recently herders have switched to using deadly chemicals sprinkled over animal carcasses and left as traps for the big cats.

The lion researcher Laurence Frank, from the University of California, said lions were dying at a "staggering rate" with as many as 75 poisoned in the past five years. Combined with other threats including loss of habitat, this could eventually see the lion become extinct, Dr Frank told CBS's 60 Minutes.

Cloud Lightning

Australia's once-in-a-century deluge worsens floods

Floods described as a once-in-a-century deluge have left thousands stranded or isolated on Australia's east coast. Nearly 4,000 people may remain cut off until the weekend, and emergency crews are conducting food and supply drops.

In Queensland, heavy rains and strong winds led to flash floods, blocking roads and causing widespread blackouts. More storms have been forecast. Meanwhile, four areas have been declared disaster zones, with some 70cm (27.6in) of rain recorded in 48 hours.

Frog

US: What is that creature?

Largest salamander
© Unknown
Local conservation agent recently investigated a Dunklin County resident's discovery of this animal, Missouri's longest salamander.
"What in the world is that? A snake, eel, possibly a salamander?"

These are the questions that likely traveled through the mind of a Dunklin County resident who recently located a strange looking creature in a ditch positioned in the front yard of his home.

According to local Missouri Department of Conservation Agent, Eric Heuring, he recently visited the area residence to exam the animal and found himself, like the homeowner, in awe.

"After arriving at the residence and taking a look at it, I found myself speechless," Heuring said of the strange find.

It turns out that the once unidentified creature is actually Missouri's longest salamander, a Three-toed Amphiuma, growing to more than 30 inches.

Better Earth

Earth's Population Limit Exceeded

Image
© US Census Bureau
Current world population - 6.8bn
Net growth per day - 218,030
Forecast made for 2040 - 9bn
There are already too many people living on Planet Earth, according to one of most influential science advisors in the US government.

Nina Fedoroff told the BBC One Planet programme that humans had exceeded the Earth's "limits of sustainability".

Dr Fedoroff has been the science and technology advisor to the US secretary of state since 2007, initially working with Condoleezza Rice.

Under the new Obama administration, she now advises Hillary Clinton.

"We need to continue to decrease the growth rate of the global population; the planet can't support many more people," Dr Fedoroff said, stressing the need for humans to become much better at managing "wild lands", and in particular water supplies.