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Permafrost in the Arctic is thawing faster than ever, according to a new US government report that also found  Arctic   seawater is war...


domenica 2 luglio 2017

"The Vanishing"

So what is development? Who does it benefit? And what is the cost we are willing to pay for it? Every generation needs to ask these questions afresh as Prerna Singh Bindra reminds us in her impassioned new book The Vanishing: India's Wildlife Crisis. It's a must-read for all who care about India's seriously wounded environment, its fast disappearing flora and fauna—yes, including the tiger—and its growing number of climate refugees.

Bindra is a leading conservation journalist who has served on several environment boards including the National (she calls it "Notional") Board of Wildlife. Her book throws alarming new light on just how precarious our few remaining natural habitats really are under the burgeoning pressures of "development" projects and the failure of those trusted with preserving them.
The deceptions of development

Development presents a dilemma: India has the world's largest population of the poor according to the World Bank so clearly we need more "development". Smart cities, clean nuclear energy, geography-defying plans to link rivers, turning our coastline into a "Sagarmala" of tourist resorts and major ports... yes, all this constitutes development. But what of "the three states that recently held elections—Punjab, Uttar Pradesh and Uttarakhand— (which) have nine of the most polluted cities in the world?" asks Bindra. She cites a study showing 1.1 million Indians die from air pollution-related causes every year i.e. two every minute. Yet pollution was not even an election issue. Let's not get into toxic food chains, the sanitation crisis, the trashing of the oceans and mountains, the submerging of Pacific islands under tons of consumer debris carried by the ocean. That is the ugly emerging face of "development."
Calling development the "largest cause of population displacements in the country," Bindra says locals benefit little from projects that displace them, causing growing dissatisfaction in the hinterland while the country pays a tremendous environmental price.
"[Saving the forests] is crucial for the economy —India's forests serve as a carbon sink tank, neutralising over 11 per cent of India's total greenhouse gas emissions. If we were to put a monetary value, this 'ecosystem service' would amount to Rs. 6,00,000 crores. Yet, we continue to clear—at a conservative estimate—no less than 135 hectares of forests a day, diverting it for various projects such as highways, mines and cement factories."
According to a World Bank report, this environmental damage already accounts for 5.7 % loss of India's GDP annually. Ironic, isn't it?
Bindra warns this "ecocide is redefining India, irrevocably altering its geography, its physical entity, striking at its ecological and economic security. When we ravage nature, we are despoiling our culture, threatening our future.

Saving tigers to drown them

In a poignant passage in the book Bindra tells us how on 23 August, 2016, the Wildlife Board sanctioned the Ken-Betwa river link project, which will drown 58 sq km of critical tiger habitat in the Panna Tiger Reserve, including its tigers. The irony is that Panna's tigers owe their existence to a groundbreaking government-supported program that brought tigers back to the park after they had been declared extinct here in 2005. Now they are facing extinction once more. There are several such accounts of forests being plundered for mines, the Barazan plateau in Goa, a major water resource, being turned into an airport, the polluting infrastructure of renewable energy plants etc which throw new light on some of India's biggest development projects.

Facing extinction

Clearly, the paradigm we have chosen for progress has serious consequences—not least for our fellow creatures. "Our planet is in the midst of the Sixth Great Extinction of plants and animals," warns Bindra, corroborating previous scientific reports.
She notes:
"As a natural phenomenon, extinction occurs at a background rate of one to five species per year; what we are losing now is between 1,000 to 10,000 species a year. It's the worst spate of die-offs since the giant meteorite that hit earth some 65 million years ago wiping out the dinosaurs...The statistics are frightening, numbing and real... Global populations of fish, birds, mammals, amphibians and reptiles have declined by an astounding 58 per cent in the four decades spanning 1970 - 2012. One in five species faces extinction. A tenth of the world's wilderness has been destroyed since the 1990s, and we are in real danger of losing it all by 2050. What it signifies is that there will be no untouched wilderness..."
Do you remember when vultures disappeared? I used to see them every evening while jogging in Delhi's diplomatic area in Nehru Park in the mid '90s. We poisoned their carrion with Diclofenac, a popular anti-inflammatory painkiller used by vets. It was the fastest decline of a bird population anywhere in the world. Does it matter if they died? Yes it does—vultures cleaned animal carcasses of potentially lethal bacteria and fungi.
Or take the case of the Great Indian Bustard, hunted to near extinction but fighting for a comeback thanks to the efforts of conservationists and a certain doctor Pramod Patil, obsessed with its fate. Bindra's book introduces us to some amazing, unsung heroes who deserve to be lauded for the stellar role they are playing in conserving endangered habitats and species. Like Odisha's Athgarh Elephant-conflict Mitigation Squad, "a rag-tag group of daily wagers" led by Panchanan Nayak, who steer 25 wild elephants safely across highways and fields simply by talking to them. Or the case of the 150 million old Oliver Ridley turtles who found their natural habitat turned into a missile testing range overnight.
The book ends on a poignant note, describing the sounds of silence in a land where sparrows once chirped, bees buzzed and the monsoon bird, the papeeha, sang the arrival of the rains. Or, as the writer John Vidal wrote:
"A great silence is spreading over the natural world even as the sound of man is becoming deafening. Little by little the vast orchestra of life, the chorus of the natural world, is in the process of being quietened."

‘The Vanishing’ Shows How Our Model Of ‘Development’ Is A Recipe For Destruction 01/07/2017 Prabha Chandran

The risk of extinction faced by many mammals has been graphically exposed in a new study.
Researchers have long assumed that 'habitat fragmentation' contributes to the extinction risk for animals, but have not been able to measure it for animals on a global scale.
In the first study of its kind, researchers have successfully measured habitat fragmentation for more than 4,000 species of land-dwelling mammals.
Among the findings, researchers discovered that species with more habitat fragmentation are at greater risk of extinction.
Study lead author Professor Kevin Crooks, of Colorado State University, said the research has implications for assessing the threat of extinction for mammals and setting priorities for global mammal conservation.
He said: 'For the first time in Earth's history, one species - Homo sapiens, or humans - dominates the globe.
'In contrast to prior eras, we travel and communicate across the entire planet.
'Unfortunately, the more "connected" we become, non-human life with which we share this planet becomes increasingly disconnected, at their peril.'
The research team used high-resolution habitat-suitability models to measure the degree of fragmentation for the world's mammals.
Scientists then examined the relationship between habitat fragmentation and extinction risk, as assessed by the International Union for Conservation of Nature Red List, and developed a comprehensive inventory of the global conservation status of animals and plants. 
The team also produced global maps, predicting key areas of intact high-quality habitat as well as hotspots of fragmentation for mammals.
Professor Crooks told MailOnline: 'There are a variety of examples of mammals at risk of extinction due to habitat fragmentation. 
'Some interesting examples include the Golden-crowned Sifaka, the Greater One-Horned Rhino, the Calamian Deer, the Cusp-Toothed Flying Fox, and the Hispid Hare.'
Habitat models demonstrate that most suitable environments for mammals are located outside of known protected areas.
Human activities such as urban development and deforestation can lead to habitat fragmentation.
Professor Crooks said fragmentation reduces the total amount of habitat available to wildlife, but also simultaneously isolates the habitat that remains, preventing movement of animals in previously connected landscapes.
In previous research, Professor Crooks and his colleagues found that large carnivores, mountain lions and bobcats, decline and at times disappear, in highly-fragmented urban areas in the United States.
He said habitat fragmentation also intensifies the effects of other agents of global environmental change, including limiting the ability of wildlife to shift locations in response to climate change.
Professor Crooks added: 'Habitat fragmentation needs to be addressed urgently, but it is also a manageable global conservation challenge.
'We hope that this research will provide critical guidance to conservation practitioners and policymakers setting strategic priorities for global mammal conservation.
'The findings of the study warrant intensified efforts to protect remnant habitat patches, as well as to restore connectivity to fragmented landscapes through conservation tools such as wildlife corridors and habitat linkages.' 

Could these mammals soon be EXTINCT? Shocking map reveals the areas where animals, including the bobcat and mountain lion, are at risk of dying out SHIVALI BEST FOR MAILONLINE 3 July 2017

7 Species nearing extinction, thanks to destructive human activities News Mobile Education Bureau
June 29, 2017

In a world where genetically modified food (GMO) is taking over the market despite their many dangers to health and environment, we are only starting to become aware of the need for fresh and organically produced vegetables. The wide variety of fruits and vegetables are slowly but definitely dying out and becoming even more difficult to procure.
A survey conducted by the Food Safety and Standards Authority of India under the Union agriculture ministry tested random samples of vegetables in markets all over India. They found that the vegetables contained very high, toxic levels of banned pesticides, and the permitted pesticide levels were more than 1000 times the permissible levels. So, what exactly are we eating? And is our food giving rise to the many health problems today?
It is not easy to always have access to farm fresh vegetables which you can trust are not sprayed with harmful pesticides. However, this Indian family came up with a solution that might soon become a trend all over India.
Dr Prabhakar Rao and his family run a 2.5 acre natural farm in Bengaluru, wherein they grow vegetables that are indigenous and native to India and yet are not grown or found anywhere in the country anymore.
Dr Rao, who holds a PhD in plant breeding and genetics, has spent his entire professional career practicing architecture all over the world. While travelling, he collected 560 native indigenous seeds of endangered vegetable species from the oldest generation of farmers.
The procured seeds were typically open pollinated, heirloom seeds, which means that new seeds can be prepared from the mother seeds, unlike the hybrid and genetically modified seeds which last for just one season.
He kept collecting the varieties and started testing them for their genetic stability and climatic adaptiveness for the Indian conditions and eventually was able to sustain 140 varieties of hyper-exotic vegetables.
Since they were open pollinated, Dr Rao was able to multiply the seeds, and he now sells them online for people to buy and grow their own seeds for further use.

How did the farm fresh idea take root?

"I belong to the generation of scientists who promoted intensive chemical farming, the generation of MS Swaminathan during the green revolution. We promoted the use of urea, pesticides and the growth of hybrid seeds. While doing my PhD during this time, I kept asking myself if this was sustainable. And therefore, I eventually changed my line to architecture," says Dr Rao.
"I was a part of a project to protect the biodiversity in the Western Ghats. I used to visit the Western Ghats very often and that's when I first realised the importance of indigenous varieties. That is when the dichotomy started," he explains.
This is when he started collecting native or heirloom varieties of seeds from all over the world.
"Unbeknownst to us, we are every year loosing hundreds and hundreds of native vegetable seeds in India," he laments about the dire ecological conditions of the country that are not easily noticed by urbanites.

Old-school farming is the way to go

The family believes that this is the way farming should be done, and farmers should be able to produce their own seeds from the previous crop, and use them season after season instead of buying genetically modified seeds every season.
"Over the past 20 years there has been a constant decline in the variety of vegetables that we eat because the original vegetables were of native indigenous varieties using which farmers could produce their own seeds every season", states Dr Rao, adding that the seed companies have such a business model that they ensure that farmers come back to buy new seeds from them every season by genetically modifying the seeds, so they last for only one season.

Hundreds of native vegetable varieties becoming extinct every year

Since 90 per cent vegetable varieties that we consume are hybrid varieties, hundreds of native vegetable varieties are becoming extinct every year.
It was his passion for the biodiversity of plants and the aim to save these varieties from getting lost that spurred Dr Rao to start Hariyalee Seeds, a farm where they grow exotic, endangered species of vegetables and promote natural farming.
Speaking about endangered vegetables, he says, "People are quite aware if a bird or an animal is becoming extinct. People talk about it, write about it. There is awareness and there is a public movement against that. But vegetables are a completely different story because nobody seems to really know how many varieties of vegetables are extinct and how bad the situation actually is."

Genetically modified seeds breaking down biodiversity: Why desi seeds are important

When farmers shifted from the practice of making their own seeds to buying seeds from the market, the seed companies started providing the farmers with seeds which they could not reproduce, while the old varieties with the farmers started becoming extinct.
This damage to our indigenous biodiversity of vegetables has accelerated in the past 5-10 years.
"Desi indigenous varieties have a huge role to play in our lives. These varieties can handle climate change, are tolerant to drought conditions, and are naturally resistant to diseases and pests. Moreover, they are adaptable to natural farming methods. Instead of taking them and making hybrids and genetically modified organisms, it makes sense for us to go back to cultivating them," says Dr Rao.

The need to create awareness

"At Hariyalee, we are trying to promote an agricultural value, which is a win-win-win. It's a win for the farmer, for the consumer and the environment. It's beneficial for the farmer because natural farming is significantly cheaper than organic farming or chemical farming because the farming inputs like bio fertilizers and bio pesticides that we use are very low cost and they work extremely well, and since our seeds are a one-time purchase, they bring the cost down for the farmer.
Farmers get to grow these hyper-exotic vegetables, which sell at a higher market rate, and therefore, get a better revenue steam and a low input cost."
He wants people to use his seeds and share them with their friends so that these exotic vegetables don't go extinct.

Towards chemical-free farming

He uses cow urine and cow dung to make his own fertilizers and pest repellents are made from the things that are available in the farm, therefore growing exotic vegetables in a completely chemical free environment.
"What we eat today is really scary! When I feed something to my family, I don't know what I'm feeding them," Dr Rao exclaims.
"And therefore, if I started spreading these exotic varieties of vegetables, people will be tempted to grow them at home. You will be surprised at how much you can grow with just a balcony or a kitchen patch," he adds.

With hundreds of native vegetables going extinct, this Indian family runs a farm with over 560 rare and exotic veggies New Delhi, July 3, 2017

Experts at the Royal Botanic Gardens Kew have just published their second ever State of the World’s Plants report. They reveal there are 390,000 known species of plants, with over 30,000 being used by humans. Unfortunately, the report also says that 1 in 5 plant species are in danger of extinction.
Plants are absolutely fundamental to humankind. Plants provide us with everything – food, fuel, medicines, timber and they are incredibly important for our climate regulation. Without plants, we would not be hereWe are facing some devastating realities if we do not take stock and re-examine our priorities and efforts.” said Prof. Kathy Willis, director of science at Kew.
The biggest driving factor behind plant extinction is the loss of habitat. Loss of habitat is caused by farming, deforestation and infrastructure expansion. Climate change isn’t currently a major contributor, but the report warns that it will have a dramatic impact on plants within the next 30 years.
On a positive note, new scientific discoveries offer hope. “I find that really encouraging and exciting. We are still finding new species of trees, new species of food: five new species of onion were found last year, for example.” says Prof. Willis.
She went on to say, “There are huge areas of the world where we just don’t know what is growing there. They may hold the key to the future of food. Genetic diversity in our foods is becoming poorer and poorer.
The report references the global challenges of “population size, land-use change, plant diseases and pests” and says preserving biodiversity is urgent, as well as finding and conserving wild relatives of crops.
Major agriculture companies like Monsanto put world food security in jeopardy by propagating homogenous crops, known as “mono-cropping”. This is in contradiction with natural evolutionary processes which promote strong diverse crops with area-specific defenses and characteristics.
As the global population rises and the pressure increases on our global food system, so does our dependence on the global crops and production systems that feed usThe price of failure of any of these crops will become very high.” says Luigi Guarino, senior scientist at the Global Crop Diversity Trust.
According to the report, “Having access to this large and diverse genetic pool is essential if we are to furnish crops with the valuable traits that enable resilience to climate change, pests and diseases, and ultimately underpin global food security.

Report: 1 In 5 Plants In Danger Of Extinction Amelia Kinney | June 20, 2017 The State of the World's Plants Report 2017

Some 1,300 miles into the Arctic Circle and just 650 miles from the North Pole lies the world’s most important freezer.
Situated on Spitsbergen Island in the Svalbard archipelago, the Global Seed Vault is owned by the Norwegian government and sits next to the world’s northernmost town, Longyearbyen, with a population of just over 2,000.
Contained within in it are 930,000 varieties of the world’s most precious seeds, sent by the gene banks across the globe to insure them against risks in their home country, such as natural disasters, war and looting.
Built to house as many as five million seed varieties, in the most extreme circumstances, the vault is intended to act as a “doomsday” depository for global agriculture, should a major catastrophe wipe out the plants we rely on. But it’s main role is in protecting diversity from threats that already exist today.
Today climate change is challenging agricultural production,” says Marie Haga, a former leader of Norway’s Centre Party and the executive director of the Crop Trust, which advises on and part-funds the vault.
“Plants have always adapted. Wheat originates in the Middle East and now we grow it all over the world, but it has taken thousands of years for wheat to move from the Middle East to somewhere like Canada. The basic problem today is that climate change is happening faster than plants are able to adapt.
The primary aim of the vault is to make sure that mankind has access to a maximum diversity of crops to be able to adapt to new challenges in the future.
According to Kew’s State of the World’s Plants report, there are currently 390,000 plant species known to science, with around 30,000 used by people. Their report estimated that one in five plants are at risk from extinction, with habitat loss the leading cause of extinction risk.
We are losing genetic diversity rapidly, both in the field and in gene banks around the world,” says Marie. “For each variety of seeds that we lose, we also lose options for the future.
Three vaults lie at the end of a 130m tunnel inside the flank of Mount Plateau, allowing the seeds to be stored deep within the Arctic permafrost. In the Vault Room the seeds are cooled to an optimal –18C.
Three times a year this unique facility opens up its doors to allow countries to make deposits in the frozen vaults. Flown in by air to the world’s northernmost airport, any collaborating gene bank has to send over at least 500 examples of a given crop variety and remain proprietors of their seeds, should they ever need them.
To the surprise of many, the bank has already been used for its intended purpose. After the International Gene Bank of Syria determined their Aleppo site was too hard to administer in 2015, the site’s administrators requested their boxes from the vault in order to replenish new research facilities in Lebanon and Morocco.
It may seem like a rarefied endeavour but there are 1,700 gene banks dotted across the world, and many are considered to be at risk as a result of lack of funding, poor infrastructure, not enough or qualified technical human resources, or information systems.
In Afghanistan, two of the country’s seed banks have been looted, not for the seeds, but for the plastic containers used to store them. Hurricane Xangsane wiped out another bank in the Philippines.
We have also lost seed collections in Iraq due to the war,” says the Crop Trust’s Marie Haga. “In China today they only use 10 per cent of the rice varieties they would have used back in 1950. In the US they have lost more than 90 per cent of their fruit and vegetable varieties in the field. So it’s very important that this material exists in gene banks, and it’s awfully important that we have backup systems”.
Locating the seed bank deep inside a mountain in the Arctic Circle is both an important security feature of Svalbard, and a failsafe if the cooling system no longer works. If the power supply is cut off or the refrigeration units fail, the inside of the mountain would maintain a steady temperature of –5 to –8C.
Although not all the seeds would be saved, a feasibility study suggested many of the deposits would last for hundreds if not thousands of years without human intervention.
Mount Plateau is also geologically stable with limited humidity and with low radiation readings inside the mountain itself.
The Norwegian government, which owns the vault, says it has a “virtually infinite lifetime” and is “robustly secured against external hazards and climate change effects”.
It certainly seemed to be the perfect site for this endeavour.
However, the government had not anticipated what has proven to be the hottest year on record, resulting in extreme weather conditions in the Arctic.
Despite having been positioned in an area where ice is supposed to remain frozen all year round, in May this year the permafrost melted, breached the bank’s entry doors and caused  water to enter the facility’s 130m long entrance tunnel.
Fortunately none of the seeds were affected by the meltwater as it refroze before it could reach the vault.
“It was not in our plans to think that the permafrost would not be there and that it would experience extreme weather like that,” Hege Njaa Aschim, from the Norwegian government, told The Guardian.
Far from being left to its own devices, the seed bank is now under 24-hour supervision while the Norwegians conduct a series of upgrades costing $4.4m (£3.4m). The Norwegian government said in a statement: 
“When water intrudes into the outer part of the seed vault, the water is immediately pumped out again by pumps that work around the clock.”
“The seeds are completely safe and no damage has been done to the facility. Globally, the Seed Vault is, and will continue to be, the safest backup of crop diversity.”
The multimillion-pound upgrade has already involved removing an electric transformer from beneath the entrance tunnel as it was found to give off heat. Drainage ditches are being dug either side of the site’s distinctive angular doors and a waterproof wall is being installed within the entrance tunnel itself.
The melting of the permafrost says a lot about the fact that climate change is real,” Marie Haga tells me.
“The challenge for maintaining diversity is not principally related to the permafrost in Svalbard, but is related to the fact that we can expect an increase in temperature of 3-4C in many parts of the world, and that is dramatic for food production.”
Extinction threats to plants may not gain the same coverage as that for tigers, whales or gorillas, but our growing need for agricultural produce, combined with the threat to biodiversity posed by climate change, could mean we see further pressures on harvests in the near future.
According to Stuart Thompson, senior lecturer in plant biochemistry at University of Westminster, “it is estimated that we have to increase food production by 70 per cent by 2050, and achieve this despite changing weather patterns and the spread of new crop diseases due to global warming”.
“The high-yielding crop varieties which we currently depend on were tailored to produce as much grain as possible under ideal conditions, not for resilience if conditions are less good, such as during flooding or drought.”
Hopefully the “doomsday scenario” that would require the site to act as an ultimate backup will never happen, but for today’s conservationists and agronomists, sites such as Svalbard are going to be increasingly important.
Gene banks are not museums,” says Luis Salazar, communications manager at the Crop Trust. “They safeguard material to be ultimately used by breeders and farmers, be it to improve our crops or used directly in agriculture.”
“The Trust is helping to build a global system of ex situ conservation wherein international, regional and national gene banks across the world work towards making sure we do have conserved and available to be used this precious, global common good - the most important agro-biodiversity needed to feed a growing world.”
“And Svalbard is but one, albeit very important, element in this rational system.”

Global Seed Vault: the Arctic’s doomsday depository that could save plant life from climate change Ashley Coates 03 July 2017

Nearly 20 extinction events in Earth’s natural history have been analyzed in a new study by David Bond from the University of Hull in the U.K. and Stephen Grasby from the University of Calgary in Canada. They found that most of the events seen in the geologic record, starting about 500 million years ago and extending until today, can be linked to periods of massive volcanic activity, which caused global warming of the atmosphere together with acidification and oxygen depletion in Earth’s oceans. Other associated kill mechanisms were acid rain, damage to the ozone layer, enhanced ultraviolet radiation, and toxic metal poisoning.
Sound familiar? All these kill mechanisms are also side effects of the human-induced climate change we’re seeing today. For a future geologist looking back at Earth’s natural record a few million years from now, things may look pretty much the same: a well-defined mass extinction event starting in the current human-dominated (or Anthropocene) era, as measured by a drop in biodiversity and indications of massive die-offs in the rock record.
Bond and Grasby find that four of the “Big Five” extinctions in Earth’s history can be related to large-scale volcanism. Interestingly, though, some of the largest magma outpourings were associated with only a small loss of biodiversity, meaning there must be some other factor determining how severe the effect on animals and plants will be. Perhaps the gas content of different kinds of volcanoes is critical, or the location where it happened, or the continental configuration at the time of the eruptions.
For one of the “Big Five” extinctions, there’s a more plausible explanation than volcanic activity: the K-T extinction event that spelled the end of the dinosaurs 65 million years ago, which is thought to have been caused by an asteroid impacting Earth. And even in this case, volcanic activity may have played a role.
Volcanoes, of course, indicate that we live on a dynamic, active planet. As long as Earth remains habitable, it will be volcanically active, and some of the eruptions will be very energetic. Now imagine one of these large-scale magmatic outpourings, with lots of gas venting, should occur at the same time human-made global warming is taking place. The result might be the largest mass extinction Earth has ever seen.
Death is a part of life. Things have to die so other things can be born 
Ancient animals went extinct for many of the same reasons that modern animals will go extinct. And the more we know about those extinction events, the better prepared we can be for future ones. Because there will be future ones.
Back in the Pliocene and Pleistocene epochs, the seas were changing. Sound familiar? It wasn’t driven by humans, but the evolving climate was having a huge impact on the ocean—some of the largest sea level changes in the last 66 million years happened during those epochs. And that was problematic for a lot of creatures.
Anthropologists already knew that a number of extinctions happened around that time and figured they were probably due to changes in ocean conditions. Those climate shifts were a natural part of the cycles of cooling and warming that our planet has gone through for millennia. Unfortunately, ancient climate change and modern, human-driven climate change aren't even on the same playing field. Our greenhouse gas emissions have caused a massive uptick in the rate of global warming. It's happening at a much faster rate than we see in the climate record, and that means it's much more challenging for species to adapt to their new normal. While ancient natural climate change was of a gentler sort, it did make sea levels go up as ice melted—but scientists had previously assumed that while rising seas impacted local populations, marine biodiversity was pretty resilient on a global scale.
Oops. As it turns out, 36 percent of marine megafauna died out at the end of the Pliocene epoch. That’s over a third of the mammals, sharks, turtles, and seabirds that died out as the climate changed. The analysis, published in Nature Ecology & Evolution, also found that marine mammals suffered the worst losses. They had 55 percent less biodiversity after the extinction, whereas sharks only lost 9 percent. And there wasn’t just less biodiversity—there was less functional diversity, too. Those might sound like the same thing, but functional diversity has a much larger impact. Biodiversity is about a loss of species, not a loss of functional roles in an ecosystem. If one seal dies off, but another species of seal fills the same niche and can grow in number to make up for the loss, it’s less of a problem. If a seal dies off and nothing else fills their ecological niche, that could spell the end. Or, at the very least, it makes the entire ecosystem more fragile, more susceptible to change.
And that’s exactly what happened at the end of the Pliocene. Marine animals, especially those living along the coasts, died off and left gaps in their place. Entire functional groups were lost, and the ones that remained were more vulnerable to future losses. Even the new species that evolved during the Pleistocene couldn’t repair the damage.
The researchers think that it wasn’t just changing temperatures that prompted these deaths. Coastal habitats were also becoming more scarce, and food along with them. Which means climate change isn’t the only way humans could contribute to a future mass extinction. The anthropocene—the era during which humans have had an inordinate impact on the Earth—could bring on the next big event.

A third of marine megafauna died in a mass extinction that we didn’t even know about Sara Chodosh June 26, 2017

Most of the frogs alive today owe a big thank you to the asteroid or comet that delivered the coup de grace to the dinosaurs.

A new study by Chinese and American biologists shows that if the calamity had not wiped the planet clean of most terrestrial life 66 million years ago, 88 percent of today's frog species wouldn't be here. Nearly nine out of 10 species of frog today have descended from just three lineages that survived the mass extinction.
The results, to be published this week in the journal Proceedings of the National Academy of Sciences, are a surprise, because previous studies of frog evolution pinpointed the blossoming of the main frog lineages today to about 35 million years earlier, in the middle of the Mesozoic era.
The new analysis of 95 genes from frogs within 44 of 55 living families shows that these three lineages started to take off precisely at the boundary between the Cretaceous and Paleogene periods -- the K-Pg boundary, formerly called the KT boundary -- when the last mass extinction occurred, and not 100 million years ago.
According to herpetologist and co-author David Wake, a University of California, Berkeley professor of the graduate school and a curator of the Museum of Vertebrate Zoology, new frog species likely radiated rapidly throughout the world because so many environmental niches were available after the animals occupying them disappeared.
"We think the world was quite impoverished as a result of the KT event, and when the vegetation came back, angiosperms dominated. That's when trees evolved to their full flowering," Wake said. "Frogs started becoming arboreal. It was the arboreality that led to the great radiation in South America in particular."
Trees are an ideal habitat for frogs not only because they allow them to escape from terrestrial predators, but also because their fallen leaves provide protection while the frogs are on the ground, breeding habitat and plenty of food, such as insects. Trees and other flowering plants took off in the late Cretaceous, and were ready for exploitation by frogs after they recovered from the extinction.
Another adaptation that became popular was direct development, that is, producing young without a tadpole stage, which is standard for about half of all frog species today.
"The majority of the frogs that thrive now are thriving because of direct development of eggs in terrestrial situations," he said. "It is a combination of direct development and use of arboreal habitat that accounts for a great deal of the radiation."
Previous genetic analyses of frog evolution focused on mitochondrial DNA and how long the molecular clock had been ticking for mitochrondrial genes. However, analysis of molecular evolution in mitochondrial DNA often produces dates for lineage divergence that are too old. In the case of frogs, such analysis pinpointed the radiation of most living frogs at about 100 million years ago, which was a puzzle, since Earth's environment was stable at that time. A changing environment typically drives evolution.
The new analysis, based on data assembled primarily by graduate student Yan-Jie Feng at Sun Yat-Sen University in Guangzhou, China, focused on the sequences of 95 genes located on chromosomes in the nucleus and how they changed over time. He and his colleagues gathered genetic data from 156 frog species and combined this with earlier information about two genes from 145 different frogs, for a total of 301 distinct frog species from all 55 families of frogs. The data were calibrated using 20 dates derived from fossils and Earth historical events.
The team, which includes scientists from the Florida Museum of Natural History at the University of Florida and the University of Texas, Austin, concluded that perhaps 10 groups of frogs survived the extinction, but only three of them (Hyloidea, Microhylidae, and Natatanura) flourished and diversified to claim habitats and niches around the world.
Nothing other than luck distinguishes the survivors, Wake said. Remnants of the other surviving lineages are scattered in isolated spots around the world, but are just as diverse today in their habitats and breeding strategies as the 88 percent.
Two of the three surviving lineages that subsequently radiated widely came out of Africa, which remained intact as the continents shifted around over the ensuing eons, with the breakup of Pangea and then Gondwana to form the continents we see today. The African rift zone and mountain building in West Africa generated new habitats for the evolving frogs, Wake noted. The third, Hyloidea, radiated throughout what became South America.
Today's frogs, comprising more than 6,700 known species, as well as many other animal and plant species are under severe stress around the world because of habitat destruction, human population explosion and climate change, possibly heralding a new period of mass extinction. The new study provides one clear message for future generations.
"These frogs made it through on luck, perhaps because they were either underground or could stay underground for long periods of time," Wake said. "This certainly draws renewed attention to the positive aspects of mass extinctions: They provide ecological opportunity for new things. Just wait for the next grand extinction and life will take off again. In which direction it will take off, you don't know."
The paper's other co-authors are David Cannatella and David Hillis at UT Austin, Peng Zhang and Dan Liang of Sun Yat-Sen and David Blackburn of the Florida Museum. Cannatella, Zhang and Liang are all former UC Berkeley postdoctoral fellows.
Support for the research was provided by the U.S. National Science Foundation, the National Natural Science Foundation of China and the National Youth Talent Support Program and National Science Fund for Excellent Young Scholars of China.

Dinosaurs' loss was frogs' gain: The upside of a mass extinction UNIVERSITY OF CALIFORNIA - BERKELEY 3-JUL-2017

An international team of researchers has announced that they have learned the genetic history of the Macrauchenia genus in South America, which has completely disappeared 10,000 years ago.
Researchers have encountered a lot of difficulties because of old and degraded DNA, according to Popular Science.
The main author of the study, published recently in Nature Communications, Mick Westbury (Potsdam University), stated that “because the ancient DNA is so degraded and contaminated by the DNA of the environment, we rely on the genome of our close relatives as unit of measure”.
In other words, they analyzed the genome by comparing it to an already known genome. Thus, they were able to recover 80% of mitochondrial DNA from a studied fossil.
The researchers concluded that Macrauchenia was related to perisodactyles, an order of non-ruminant herbivorous mammals, although it was not on the same genealogical line as the current species. Scientists estimate that the time this genealogy line individualized was 66 million years ago, even during the mass extinction that led to the disappearance of dinosaurs – a period in which mammals had room for diversification.
However, the divergence of this evolutionary line is not due to the disappearance of dinosaurs. Ross Mac MacPhee, a researcher in this study, claims that “although coincidence with the extinction of dinosaurs has been taken into account, our dating is not precisely accurate. Although fossils support the idea that modern placental mammalian commands have begun to diversify during this period, genetic evidence suggests that their more complex relationships go before the extinction event. ”
The genus Macrauchenia contained animals that, in their form, contradicted Charles Darwin and paleontologist Richard Owen. Even the name of the genre translates into a “long lump”, a hybrid of a brass and a camel, but the hooves resembled those of a rhino. The bizarre thing was the nose: unlike most mammals, the nostrils were in the upper part of the skull.

One of the great puzzles that contradict Darwin 150 years ago was resolved 

Il DNA È MOBILE Mar 17, 2009



“Defiant Earth" Anthropocene and the Human Extinction  4 APRILE 2017

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