Wednesday, 4 December 2019

People, climate, and water supply all played a role in the extinction of Australia's megafauna

NOVEMBER 25, 2019 


The mystery of the role of people and climate in the fate of Australian megafauna might have been solved in a breakthrough study published today. 

"Megafauna,' giant beasts that once roamed the continent—including wombat-like creatures as big as cars, birds more than two meters tall, and lizards more than seven meters long—became extinct about 42,000 years ago. But the role of people in their demise has been hotly debated for decades. 

The new study, led by a team of researchers from the ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH), analyzed fossil data, climate reconstructions, and archaeological information describing patterns in human migration across south-eastern Australia. 

The team developed and applied sophisticated mathematical models to test scenarios to explain regional variation in the periods during which people and megafauna coexisted. 

For the first time, the research suggests a combination of climate change and the impact of people sealed the fate of megafauna, at least in south-eastern Australia. And that distribution of freshwater—a precious commodity for animals and people alike as the climate warmed—can explain regional differences in the timing at which megafauna died out. 

"There has been much debate among scientists about what conditions led to this extinction event," said lead author Dr. Frédérik Saltré, Research Fellow and Coordinator of the Global Ecology Lab at Flinders University. 

"Resolving this question is important because it is one of the oldest such extinction events anywhere after modern human beings evolved and left Africa," he added. 

The findings, published in Nature Communications, are the result of analysis and complex modeling based on data including more than 10,000 fossils and archaeological records. Using high-quality fossil data and archaeological evidence of human activity, the researchers were able to map regional patterns of megafauna extinction. 








How species in the wild are managing the risks and rewards of sharing space with humans

NOVEMBER 25, 2019 

by Elizabeth Allen, University of Lincoln

Endangered monkeys living in the wild are intelligently adapting their lifestyle to fit with their human neighbors, learning to avoid manmade risks and exploiting increased contact with people, new research has revealed. 

The study, which looks specifically at the behavior of an endangered monkey species, reveals that even in national parks where human presence is reduced and regulated, the animals carry out careful calculations and modify their natural behavior to balance the pros and cons of living in close proximity to humans. 

It reveals the negative impact that consuming human foods can have on the physical health of the monkeys, and highlights the need for new and sustainable conservation programs to save the growing number of endangered species in their natural habitats

Barbary macaques are an endangered species of monkeys restricted to the forests of Morocco and Algeria, with an introduced population also living on the Rock of Gibraltar. The wild population in North Africa has dramatically declined in the last decades. 

The new study, led by Dr. Bonaventura Majolo from the University of Lincoln, UK, involved a detailed examination of the effects of human activity on wild Barbary macaques in Ifrane National Park in Morocco. 

Dr. Majolo said: "When we observe animals in the wild we often talk about a 'landscape of fear.' This term refers to the decisions that animals make when they choose whether or not to avoid an area where the risk of predation is highest; weighing up the risk of attack against the possible rewards to be found there. 

Dung beetle discovery revises biologists' understanding of how nature innovates

NOVEMBER 21, 2019 


When studying how organisms evolve, biologists consider most traits, or features, as derived from some earlier version already present in their ancestors. Few traits are regarded as truly "novel." 

Insects were wingless, then winged. Animals were blind, then had eyes. 

And in biology textbooks, novelty has a strict definition: it must have no relationship to any structure found in an ancestor and no relationship to any other body part elsewhere in the organism. By this definition, a dolphin's pectoral fins are not a novelty because they are modified forelimbs that already existed. 

However, some experts argue this creates a problem since it means novelty must seemingly arise from nothing. It must "pop up out of the blue" in evolutionary time. 

Now evidence has emerged—in a study published Nov. 21 in the journal Science—that illuminates how new things can evolve. Moreover, this evidence has come from an unexpected source: the small, yet charismatic dung beetle. 

"Dung beetles are fascinating creatures," said Armin Moczek, the study's senior author and a professor in the IU Bloomington College of Arts and Sciences' Department of Biology. Among their many qualities, one structure has placed them at the forefront of discussions about novelty among researchers. That structure is their thoracic horn, which is regarded as a textbook example of an evolutionary novelty. This is because the thoracic horn is unique to horned beetles, and it appears to have no relationship to any other structure in the animal. 

Searching for frogs in the jungles of Borneo – via Herp Digest


Borneo’s jungle feels full of life during daylight, but it’s at night — when its wild denizens are on the hunt for food — that the forest really comes alive.October 6,2019
By Charlotte Wigram-Evans
Published in the Adventure guide, distributed with the October 2019 issue of National Geographic Traveller (UK)

Darkness comes quickly in the jungle. It snakes around the branches of the acacia tree, rises from the crevices between buttress roots and envelops the mushrooms puffing up from the ground like clouds. It flows up the ironwood tree, obscuring the vines that hold its trunk in their slow, crushing embrace. It comes without warning, as though the sun has simply been plucked from the sky. And it’s only then, when it’s as black as obsidian, that the jungle wakes up.

I peer hopelessly into the gloom, my eyes straining for any signs of life emanating from the makeshift camp I’d trekked to earlier that day. My guides may be silent, but the jungle has turned the volume up to full blast; cicadas scream, bats squawk and the babble of a nearby steam is interrupted by deep, rhythmic belches — giant river frogs. It’s these monstrous burps that seem to rouse the group from their afternoon kip. Suddenly, Kajan’s voice roars out, his words escaping into the night: “Right, frogging time!”

I scramble frantically for my torch. Is this some kind of bizarre fairytale? Am I being led out into the wild to kiss frog after frog until I find a prince? My fingers find the plastic switch, and grinning faces suddenly appear above me: Munati, Rantau, Dali and Kajan, four members of the Iban tribe that has eked out an existence from Borneo’s forests for centuries. Their deep understanding of the jungle is unmatched. 
The amphibians, it turns out, will be my dinner, not my date. Rantau hands me a plastic bag and I wade out into a stream behind him as he regales me with tales of his frogging prowess. “I held the record in my longhouse for the most caught in one night,” he says gleefully. “More than 100.”

In the feeble beam of my torch, I watch as his hands plunge into the water ahead of me, and emerge with a frog as big as teapot. Its bulbous, saucer-sized eyes stare at me ruefully, before it’s dropped into a bag already bulging with others.

I splash on, creatures that have been ensconced in tree trunks all day peering down at me from the canopy. The paper-thin wings of a lesser bamboo bat hold me spellbound, before they unfurl to reveal a tiny, fang-toothed face, lamp-like eyes aglow. A few slippery metres further downstream I spot a jumping spider, busy weaving its web.

The rainforest itself feels more alive in the blackness, as though the trees have woken up with the wildlife. Sinewy vines seem intent on stroking my shoulders, leaves rustle around my ankles, branches lean out over the stream, bowing under their own weight. I’m so in awe of this ecosystem that Kajan has to make regular U-turns, dashing back to ensure the jungle hasn’t claimed me for its own.

Unsurprisingly, my bag remains firmly frogless. “No stew for you,” Dali jokes, holding his bounty aloft like a trophy. “I got 15; Rantau still beat me, though, he’s on 20. We’ll stew them with lemongrass and ginger back at camp,” Kajan says, as we turn around and head upstream. “A true Iban delicacy.”

Food is the last thing on my mind, however — I’ve spotted an orangutan nest ahead, an expertly folded throne of palm fronds so fresh it might have been vacated only moments before. Was the great ape watching me from the trees, just out of reach of my torch beam? Two more eyes in the darkness, following my every move.

Giant river frogs are a delicacy for the Iban tribe, who set off at night in search of the amphibians. 

Jungle survival guide

Shelter
Keeping dry is crucial in the humid jungle. The easiest way to build a basic shelter is to find a long straight branch and lean it against a tree, propping up shorter branches down its length. Finally, cover it all with leaves and you’re good to go.

Equipment
The Iban would never dream of setting off into the jungle without, at the very least, a machete and a lighter. If a machete is unavailable to you, a penknife will suffice — a blade is essential when preparing food and splicing dry wood for a fire.

Water
Streams aren’t the only source of water in the jungle. Bamboo collects water in its stem, which can be accessed simply by bending the top so it flows out. Any of the giant leaves in the jungle can easily be fashioned into a makeshift cup to collect rainwater.

Food
Hunting requires expertise, so your jungle diet will be mainly plants, fruit, insects and fish, frogs, grubs and termites. Mushrooms can be lethal, so avoid if in any doubt. Also, rub leaves on skin and lips before eating to see if there’s any reaction.

Danger
From poisonous snakes to malaria-carrying mosquitos, the jungle can be a perilous place. Fashion a sturdy stick into a spear for self defence. When building a shelter, look for a dry clearing — this will keep you safe from leeches and falling branches.

How to do it
Borneo Adventure offers trips to Batang Ai National Park to visit the Iban tribe at Nanga Sumpa Lodge and explore the rainforest. Three nights with all meals from £250 per person, excluding flights. 

Monday, 2 December 2019

Sumatran rhino is extinct in Malaysia as lone survivor dies

NOVEMBER 24, 2019 

The Sumatran rhinoceros has become extinct in Malaysia, after the last of the species in the country succumbed to cancer. 

The Wildlife Department in eastern Sabah state on Borneo island said the rhino, named Iman, died of natural causes Saturday due to shock in her system. She had uterine tumors since her capture in March 2014. 

Department director Augustine Tuuga said in a statement that Iman, who reportedly was 25 years old, was suffering significant pain from growing pressure of the tumors to her bladder but that her death came sooner than expected. 

It came six months after the death of the country's only male rhino in Sabah. Another female rhino also died in captivity in 2017 in the state. Efforts to breed them have been futile but Sabah authorities have harvested their cells for possible reproduction. 

"Despite us knowing that this would happen sooner rather than later, we are so very saddened by this news," said Sabah Deputy Chief Minister Christina Liew, who is also environment minister. 

Liew said that Iman had escaped death several times over the past few years due to sudden massive blood loss, but that wildlife officials managed to nurse her back to health and obtained her egg cells for a possible collaboration with Indonesia to reproduce the critically endangered species through artificial insemination

The Sumatran rhino, the smallest of five rhinoceros species, once roamed across Asia as far as India, but its numbers have shrunk drastically due to deforestation and poaching. The WWF conservation group estimates that there are only about 80 left, mostly living in the wild in Sumatra and Borneo in Indonesia. 

Related Posts with Thumbnails

ShareThis