May 3, 2015 at 2:17 pm #20969
Dr Dominguez-Bellow was surprised by some of the findings – the microbes from their skin and gut were 40% more diverse than those of modern, urbanised people.
“In the intestine they have a diversity that really shocked us, which we think are providing a lot of important roles in digestion and in communicating with our immune system.
“We want to understand what are the bacteria that we have lost and what were their functions – and can we restore them eventually?”
In contrast, the microbes found in the mouths of the Yanomami had a similar balance to those of Western urban dwellers, something researchers think could result from their habit of chewing tobacco – a mild antiseptic – from an early age.
One other surprising finding was that the microbes from the Yanomami have antibiotic resistance genes despite never having encountered modern antibiotics – although they are not “switched on”.
Dr Dantas said they found half a dozen resistance genes. He said: “Antibiotic resistance is a natural feature of bacteria in the human body. It’s not something created by antibiotic use. But it does get amplified when antibiotics are used.”
This “baseline” microbiome from the isolated Yanomami has also been compared with other hunter-gatherers from Malawi, as well as Guahibo Amerindians, who are already moving towards urban living with access to medical care and changing agricultural practices.
It was found that the more exposed a group was to modern life, the less diverse the microbiome.
He says more research is now needed to understand the role of these resistance genes – to understand the effect on the immune system and metabolism.
And once we know, could we simply “top up” our microbes to reduce the impact of modern life?
Dr Dantas believes that there will be a commercial interest in “bioprospecting” or developing synthetic compounds to modulate the effects of modern life.
But he still believes we have a responsibility to reduce our antibiotic use – and maybe not to be so obsessed with cleanliness.
“I found my two-year-old tucking into some hay and manure which my parents have delivered to my home for the garden.
“I’m hoping the bacterial load had dropped as it dried out.”May 19, 2015 at 2:52 am #21247
Water and sugar have already been shown to move from older trees into the mycelial network (they are feeding the fungi, after all), so it’s possible including young trees in the network helps establish them by providing them with food while they are still trying to stand on their own two feet; indeed, this has been demonstrated experimentally before. You can also see what this implies about only cutting the biggest trees in the forest — doing so greatly diminishes the connectedness and hence resilience of the network.
To my surprise, I discovered when researching this post that it has also been known for a while that trees of different species can communicate with and support one another via their mycorrhizae. It’s long been known that plants can communicate with unrelated species through the air; plants getting chomped by herbivores release volatile chemicals that are sensed by neighboring plants, who up their defenses pro-actively just in case. But communicating — and even sharing resources — through mutual root fungi was news to me.June 4, 2015 at 5:16 pm #21430
The Atlantic Rainforest of Brazil harbors a highly unique group of frogs that have intrigued naturalists for over a century. Known as Brachycephalus, these frogs are among the smallest terrestrial vertebrates, with adult sizes often not exceeding 1 cm in length, leading to a variety of changes in their body structure, such as reduction in the number of toes and fingers. In addition, many species of Brachycephalus are brightly colored, possibly as a warning to the presence of a highly potent neurotoxin in their skin known as tetrodotoxin.
Most species of Brachycephalus are highly endemic, being found exclusively on one, or a few, adjacent mountaintops. Such high levels of endemism is caused by their adaptation to a specific kind of habitat – the cloud forests – which simultaneously prevents them from migrating across valleys and promotes the formation of new species.
The first species of Brachycephalus was described in 1842 by the famous German naturalist Johann Baptist von Spix, yet most species in the genus have been discovered only in the past decade, particularly due to their highly endemic nature and the difficulty in reaching remote montane sites. Over the course of five years of fieldwork, a team of researchers has provided the largest addition to the known diversity of Brachycephalus, with seven new species.June 9, 2015 at 7:50 pm #21496
In the alpine grasslands of eastern Africa, Ethiopian wolves and gelada monkeys are giving peace a chance. The geladas – a type of baboon – tolerate wolves wandering right through the middle of their herds, while the wolves ignore potential meals of baby geladas in favour of rodents, which they can catch more easily when the monkeys are present.
The unusual pact echoes the way dogs began to be domesticated by humans (see box, below), and was spotted by primatologist Vivek Venkataraman, at Dartmouth College in New Hampshire, during fieldwork at Guassa plateau in the highlands of north-central Ethiopia.
Even though the wolves occasionally prey on young sheep and goats, which are as big as young geladas, they do not normally attack the monkeys – and the geladas seem to know that, because they do not run away from the wolves.June 20, 2015 at 1:11 am #21616
The oft-repeated claim that Earth’s biota is entering a sixth “mass extinction” depends on clearly demonstrating that current extinction rates are far above the “background” rates prevailing in the five previous mass extinctions.
Earlier estimates of extinction rates have been criticized for using assumptions that might overestimate the severity of the extinction crisis. We assess, using extremely conservative assumptions, whether human activities are causing a mass extinction.
First, we use a recent estimate of a background rate of 2 mammal extinctions per 10,000 species per 100 years (that is, 2 E/MSY), which is twice as high as widely used previous estimates. We then compare this rate with the current rate of mammal and vertebrate extinctions. The latter is conservatively low because listing a species as extinct requires meeting stringent criteria. Even under our assumptions, which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 114 times higher than the background rate. Under the 2 E/MSY background rate, the number of species that have gone extinct in the last century would have taken, depending on the vertebrate taxon, between 800 and 10,000 years to disappear. These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way. Averting a dramatic decay of biodiversity and the subsequent loss of ecosystem services is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing.July 23, 2015 at 5:32 pm #22121July 24, 2015 at 4:48 am #22124
Polar bear metabolism cannot cope with ice loss
The Arctic mammals may not survive the ongoing loss of their hunting grounds.July 28, 2015 at 2:32 am #22145
I think it is just some of them, the ones that we know about…but I’m glad someone did it
Here’s Every Single Animal That Became Extinct In The Last 100 YearsJuly 29, 2015 at 6:22 pm #22227August 2, 2015 at 2:42 pm #22301
Russian Sable, Barguzin Nature Reserve, Buryatia, on Lake Baikal
There are only 20-30August 15, 2015 at 4:03 pm #22480
Ray’s team began by putting Florida carpenter ants (Camponotus floridanus) on glass slides under a microscope and zooming in 1,000 times on their antennae, so they could see the hundreds of tiny sensory hairs that coat them. Next, they inserted a very thin glass electrode into a single sensory hair in order to record any biochemical activity on the insects’ antennae. In doing so, they were able to pinpoint the exact chemicals that ants could smell emitting from the queen, the workers and from ants from another colony.August 15, 2015 at 4:23 pm #22481
We’re on day who-the-heck-knows of the Android Stagefright security vulnerability, and there’s really no point keeping track of the days because no one’s going to fix it. The Android ecosystem can’t deal with security, and it won’t change until it’s too late.September 4, 2015 at 2:33 pm #22592
Although most of the world’s biodiversity is below ground, surprisingly little is known about how it affects ecosystems or how it will be affected by climate change. A new study demonstrates that soil bacteria and the richness of animal species belowground play a key role in regulating a whole suite of ecosystem functions on Earth. The authors call for far more attention to this overlooked world of worms, bugs and bacteria in the soil.
Ecosystem functions such as carbon storage and the availability of nutrients are linked to the bugs, bacteria and other microscopic organisms that occur in the soil. In fact, as much as 32% of the variation seen in ecosystem functions can be explained by the biodiversity in the soil. In comparison, plant biodiversity accounts for 42%. That is the conclusions of a new study published in Nature Communications led by Peking University and the Center for Macroecology, Evolution and Climate at the University of Copenhagen.September 4, 2015 at 6:55 pm #22593
Genetic analysis has shown the bacteria – Pasteurella multocida and Clostridia perfringens – were ordinary types commonly found in the bodies of ruminants like saiga.
WHAT IS THE SAIGA ANTELOPE?
Huge herds of saiga once roamed the earth alongside the wooly mammoth and the sabre-toothed tiger.
The mammoth and tigers died out but the saiga became prized for its delicious meat, which resembles succulent lamb.
There were more than 1 million saiga in the 1990s, but by 2003 poaching and disease slashed their numbers in Kazakhstan to 21,000.
They play a key role in the ecosystem of the steppe grasslands by recycling nutrients back into the soil through their dung.
They are also a vital food source for the predators that prowl the steppes.
They do not normally cause disease in the animals unless they have weakened immune systems and if a disease-causing strain was spreading in the herds, the die-offs should have taken much longer.
Carlyn Samuel, from the Saiga Conservation Alliance, which has been leading the efforts to understand what happened, said: ‘The most likely primary disease appears to be haemolytic septicaemia, caused by an opportunistic infection with the bacterium Pasteurella multocida serotype B, which is naturally found as a latent infection in the upper respiratory tract of saigas and other mammals.
‘Another opportunistic super-infection with the bacteria Clostridium perfringens was also identified in some cases – perhaps a half – and this infection results in the release of massive amounts of lethal toxins into the intestine, which are absorbed into the bloodstream and contribute to a rapid death.
‘However, it is not clear what triggered these bacteria suddenly to become virulent.’
Over just four days, 60,000 of the antelope perished, a rate of spread that defies conventional epidemiology of disease.September 17, 2015 at 5:48 pm #22764
The Next Great Extinction Crisis Is Under Way Under the SeaSeptember 20, 2015 at 3:55 pm #22771
Tens of thousands of smaller trees have been published over the years for select branches of the tree of life—some containing upwards of 100,000 species—but this is the first time those results have been combined into a single tree that encompasses all of life. The end result is a digital resource that available free online for anyone to use or edit, much like a “Wikipedia” for evolutionary trees.
“This is the first real attempt to connect the dots and put it all together,” said principal investigator Karen Cranston of Duke University. “Think of it as Version 1.0.”
The current version of the tree—along with the underlying data and source code—is available to browse and download at https://tree.opentreeoflife.org.
It is also described in an article appearing Sept. 18 in the Proceedings of the National Academy of Sciences.
Evolutionary trees, branching diagrams that often look like a cross between a candelabra and a subway map, aren’t just for figuring out whether aardvarks are more closely related to moles or manatees, or pinpointing a slime mold’s closest cousins. Understanding how the millions of species on Earth are related to one another helps scientists discover new drugs, increase crop and livestock yields, and trace the origins and spread of infectious diseases such as HIV, Ebola and influenza.
Rather than build the tree of life from scratch, the researchers pieced it together by compiling thousands of smaller chunks that had already been published online and merging them together into a gigantic “supertree” that encompasses all named species.
The initial draft is based on nearly 500 smaller trees from previously published studies.
To map trees from different sources to the branches and twigs of a single supertree, one of the biggest challenges was simply accounting for the name changes, alternate names, common misspellings and abbreviations for each species. The eastern red bat, for example, is often listed under two scientific names, Lasiurus borealis and Nycteris borealis. Spiny anteaters once shared their scientific name with a group of moray eels.October 5, 2015 at 2:26 pm #22899
When lunge-feeding, the whale accelerates and opens its mouth, taking in a volume of prey-laden water up to 130 percent of its weight. Its throat distends, filling with water, and then it uses throat muscles and its tongue to force water out of its mouth through baleen plates that act as a sieve to keep the krill.
Blue whales eat up to around 3628 kg (4 tons) of krill daily.
“The whales are much more actively assessing their environment and taking advantage of prey in ways that were unknown before, to maximize energy gain,” added ecologist Ari Friedlaender of Oregon State University’s Marine Mammal Institute.
The study included information from more than 50 whales, using tags applied via suction cups and data on prey.
Blue whales, found in all the world’s oceans, are listed as endangered thanks to 20th century whaling that drove them nearly to extinction. There are about 10,000 worldwide. They reach up to about 98 feet (30 meters) long and 180 tons.
“Blue whales face a gauntlet of risks in the ocean from ship-strikes to human noise, and for an animal living on the knife-edge these dense patches of prey are critical to put on mass and ultimately reproduce,” Hazen said.October 6, 2015 at 12:45 pm #22903
Almost a third of cactuses are at risk for extinction because of threats including illegal trade and a spread of farms in arid areas, making the spiny plants among the most vulnerable species, scientists said Monday.October 8, 2015 at 10:43 am #22907
Scientists have confirmed the third-ever global bleaching of coral reefs is under way and warned it could see the biggest coral die-off in history.November 20, 2015 at 6:05 pm #23424
It was Dr Soma and her colleagues in Japan, he said, who first suggested turning a high-speed camera on the birds.
“We work mainly on the songs. They thought it would be interesting to also study dancing, and they were right. It’s a really fascinating feature.”
The team studied 16 blue-capped cordon-bleus – a species of waxbill native to sub-Saharan Africa. Eight males and eight females were paired up randomly for multiple two-hour sessions, totalling more than 200 hours of footage.
“It wasn’t very easy to record the behaviours because these birds are very choosy, and they only perform courtship displays to the individuals they like,” Dr Soma told the BBC.
So she and her student Nao Ota had to try a few different combinations – but eventually they got the footage they were after: nearly all the males and half the females were filmed, at 300 frames per second, performing their bobbing and singing displays.
Watching the slow-motion footage for the first time was a big moment, Dr Soma said. “We were so excited! It was really interesting. I just kept thinking, this could be a good paper…”December 27, 2015 at 7:19 am #23968
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