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Changing Ecology of Oceans: Study shows mass extinctions of larger Marine animals

In past extinctions, smaller creatures were more prone to die off but in the Earth's oceans these days, the bigger a species is, the more chances of it to go extinct

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FILE - A blue whale is shown near a cargo ship in the Santa Barbara Channel off the California coast, Aug. 14, 2008. The oceans are turning into a Darwinian topsy-turvy place, where it’s survival of the smallest and the bigger a species is, the more prone it is to die off. VOA
  • Blue whale is on the IUCN endangered list and has lost as much as 90 percent of its population in the last three generations
  • The proportion of species that are threatened increases enormously as body size increases
  • The mass extinction 65 million years ago that killed off the dinosaurs didn’t kill off bigger marine species at higher rates than smaller ones, unlike what’s happening now

Sept 16,2016: In the Earth’s oceans these days, the bigger a species is, the more prone it is to die off. That’s unheard of in the long history of mass extinctions, a new study finds.

As subfamilies of marine animal species — called genera — grow larger in body size, the likelihood of them being classified as threatened with extinction increases by an even greater amount, according to a study published Wednesday in the journal Science. In past extinctions, smaller creatures were more prone to die off, or size didn’t matter, said study lead author Jonathan Payne, a paleobiologist at Stanford University.

Almost none of the genera that have species averaging 0.4 inches (1 centimeter) long are threatened with extinction. However, 23 percent of those that are 3.9 inches (10 centimeters) are threatened, 40 percent of those that are 39 inches (1 meter) are endangered and 86 percent of those that are 32.8 feet (10 meters) are vulnerable, Payne said.

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These are species that are not extinct yet, but are on the respected Red List of threatened and endangered species created by the International Union for the Conservation of Nature.

“The proportion of species that are threatened increases enormously as body size increases,” Payne said.

Take the blue whale, not only the largest living animal, stretching close to 100 feet long, but the largest to ever have existed, Payne said. It’s on the IUCN endangered list and has lost as much as 90 percent of its population in the last three generations, according to the IUCN.

FILE – A 70-foot female blue whale, that officials believe was struck by a ship, is seen washed ashore near Fort Bragg, California, Oct. 20, 2009. As subfamilies of marine animal species grow larger in body size, the likelihood of them being classified as threatened with extinction increases by an even greater amount, according to a study published Sept. 14, 2016. VOA

On the other end of the spectrum is a grouping of fish, bioluminescent bristlemouths, that are about three inches long. They are the most abundant creatures with a backbone; the population is estimated to be in the trillions.

Focus on oceans

Payne compared fossil records, looked at past mass extinctions and compared them to current threats, concentrating on 264 genera that have the best modern and ancient records. Payne concentrated on oceans, where the fossil records are better over time. The mass extinction 65 million years ago that killed off the dinosaurs didn’t kill off bigger marine species at higher rates than smaller ones, unlike what’s happening now, Payne said.

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The study “shows us how unusual this crisis of biodiversity we have right now,” said Boris Worm, a top marine scientist at Dalhousie University in Canada. He wasn’t part of the study but praised it. “We have had mass extinctions before. This one is totally different than what has happened before.”

Worm spoke from a break during research in Canada’s Bay of Fundy, where after a more-than-20-year career he finally saw his first underwater right whale and basking shark.

“They are both in trouble and both among the largest of their kind,” Worm said.

Humans suspected

Payne’s study didn’t try to explain why larger animals were more threatened, but both he and Worm point to one main suspect: humans. Mostly through fishing and hunting, but also through environmental degradation such as warmer and more acidic oceans, humans have made it tougher for the biggest marine animals to survive, they said.

Catherine Novelli, the U.S. undersecretary of state for environment, said a world oceans conference that starts Thursday in Washington, will see the announcement of “many more” areas where nations set aside large areas of the seas where animals are protected and fishing is prohibited.

Duke University biologist Stuart Pimm also praised the study as both compelling and disturbing because “even if some species do hang on, we have massively changed the ecology of much of the oceans.”

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Payne said there is still hope, since these species haven’t gone extinct yet. He points to northern elephant seals which had a population below 100 in the early 1910s, but are now more than 100,000 strong. But they are the exception.

“It pains you to the core to know that these animals might be gone in a generation or two,” Worm said. “You can’t imagine a world without them. It’s such an important and beautiful part of our planet.” (VOA)

  • Manthra koliyer

    The sea animals are at a high risk of extinction due to Human intervention also.

  • Antara

    Bigger marine animals are more prone to be extincted! Tragic indeed!

  • Arya Sharan

    Human intervention in the aquatic environment has just made things worse.

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Health and Future of Every Child Under Threat Due to Climate Change: Report

Every child's future under threat from climate change, says environmentalists

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Climate Change
The health and future of every child and adolescent worldwide is under immediate threat from climate change. Pixabay

The health and future of every child and adolescent worldwide is under immediate threat from ecological degradation, climate change and exploitative marketing practices that push fast food, sugary drinks, alcohol and tobacco at children, said a new report on Wednesday.

No single country is adequately protecting children’s health, their environment and their futures, according to the report by a commission of over 40 child and adolescent health experts from around the world.

The commission, convened by the World Health Organization (WHO), the United Nations children’s agency, Unicef, and medical journal the Lancet, found that while the poorest countries need to do more to support their children’s ability to live healthy lives, excessive carbon emissions –disproportionately from wealthier countries — threaten the future of all children.

Climate Change
Climate change can have ill-effects on the health of children and may push them to consume unhealthy food. Pixabay

“Despite improvements in child and adolescent health over the past 20 years, progress has stalled, and is set to reverse,” said former Prime Minister of New Zealand and Co-Chair of the Commission, Helen Clark.

“It has been estimated that around 250 million children under five years old in low- and middle-income countries are at risk of not reaching their developmental potential, based on proxy measures of stunting and poverty. But of even greater concern, every child worldwide now faces existential threats from climate change and commercial pressures,” Clark said.

The report, titled “A Future for the World’s Children?”, includes a new global index of 180 countries, comparing performance on child flourishing and sustainability, with a proxy for greenhouse gas emissions, and equity, or income gaps.

India ranked 131 among the 180 countries in the index.

The index shows that children in Norway, the Republic of Korea, and the Netherlands have the best chance at survival and well-being, while children in the Central African Republic, Chad, Somalia, Niger and Mali face the worst odds.

However, when the authors took per capita CO2 emissions into account, the top countries trail behind: Norway ranked 156, the Republic of Korea 166, and the Netherlands 160.

Each of the three emits 210 per cent more CO2 per capita than their 2030 target.

Climate Change
Every child worldwide now faces existential threats from climate change and commercial pressures. Pixabay

The US, Australia, and Saudi Arabia are among the ten worst emitters.

If global warming exceeds 4 degree Celsius by the year 2100 in line with current projections, this would lead to devastating health consequences for children, due to rising ocean levels, heatwaves, proliferation of diseases like malaria and dengue, and malnutrition, said the report.

The only countries on track to beat CO2 emission per capita targets by 2030, while also performing fairly (within the top 70) on child flourishing measures are: Albania, Armenia, Grenada, Jordan, Moldova, Sri Lanka, Tunisia, Uruguay and Vietnam.

The report also revealed the distinct threat posed to children from harmful marketing. Evidence suggests that children in some countries see as many as 30,000 advertisements on television alone in a single year, while youth exposure to vaping (e-cigarettes) advertisements increased by more than 250 per cent in the US over two years, reaching more than 24 million young people.

Also Read- Why Translation Can Help Businesses Access Global Market Opportunities

Children’s exposure to commercial marketing of junk food and sugary beverages is associated with purchase of unhealthy foods and overweight and obesity, linking predatory marketing to the alarming rise in childhood obesity, said the report.

The number of obese children and adolescents increased from 11 million in 1975 to 124 million in 2016 – an 11-fold increase, with dire individual and societal costs. (IANS)