With only seven northern white rhinos left in the world, creating eggs and sperm from stem cells offers the possibility of salvaging some of the species.
What’s the News: In an effort to help preserve endangered rhinos and primates, biologists have converted skin cells taken from the animals into pluripotent stem cells, which can grow into nearly anything, given the right conditions. They might even grow into egg and sperm cells, eventually, the researchers think, suggesting a cell biological route to conservation.
What’s the News: Sometimes, finding out you don’t know everything is a wonderful surprise. Videos captured by motion-sensitive cameras in remote Afghanistan show that there are more snow leopards out there than we thought.
It’s no secret that an alarming number of species around the world, especially vertebrates, are in trouble. But is the notion that the Earth is on the brink of a sixth major extinction event—the first since the dinosaur die-off—true, or alarmist? In Nature this week, a team of scientists sought to answer the question directly by counting as many species (and extinctions) as they could in the fossil record and the recent historical record. The result is gloomy news: There’s still a chance to avert much of the crisis, but if nothing changes, such a mass extinction event really could happen in the span of just a few centuries.
Mass extinctions include events in which 75 percent of the species on Earth disappear within a geologically short time period, usually on the order of a few hundred thousand to a couple million years. It’s happened only five times before in the past 540 million years of multicellular life on Earth. (The last great extinction occurred 65 million years ago, when the dinosaurs were wiped out.) At current rates of extinction, the study found, Earth will enter its sixth mass extinction within the next 300 to 2,000 years. [MSNBC]
That range of time the researchers give is so large because of the great diversity of life—it makes it hard to track exactly how many species are disappearing, and how quickly. (Indeed, DISCOVER has covered how biologists are discovering many new species these days just as those species face extinction). So Anthony Barnosky and his team made conservative estimates based on the available evidence. For instance, they pegged the rate of mammal extinction at 80 species out of a total of 5,000-plus in the last five centuries. That may not sound like much, but when you consider the speed at which things typically happen on a geologic scale, it is a faster rate of species loss than the previous five mass extinctions saw, scientists believe.
Good news for one of the most endangered mammals on the planet: Cameras set up to track the rare Javan rhino in Indonesia have captured images of young calves, showing the species is still breeding.
“This is fantastic news because before these camera trap images surfaced, only 12 other Javan rhino births were recorded in the past decade,” WWF-Indonesia Ujung Kulon programme chief Adhi Hariyadi said. “The population in Ujung Kulon represents the last real hope for the survival of a species that is on the brink of extinction.” [AFP]
Scientists who track the species had feared that perhaps as few as 40 Javan rhinos remained. This video footage recorded in November and December of last year, as well as other observations, suggests that the population is probably a little larger now, but still only about 50.
The drastic changes in the Arctic wrought by global warming aren’t just threatening that icon of climate change the polar bear, they’re also jeopardizing the health of other species–like the Pacific walrus. Environmentalists petitioned the federal government years ago to add the walrus to the endangered species list, but progress on the case has been slow. Now, in a decision that has angered both activists and oil drillers, the U.S. Fish and Wildlife Service has decided that even though our be-blubbered friends deserve recognition under the Endangered Species Act, there are just too many other endangered animals to take care of first.
Specifically, the organization’s spokesman, Bruce Woods, said that protecting walruses was advised but “precluded.” That’s because other animals, like polar bears and certain species of sea birds, are more imperiled in this world of receding ice. The agency also said it’s hampered by lack of firm data on walrus population numbers.
“The main thing is that, compared to the polar bears, there are a lot of them,” Woods said of the Pacific walrus, adding that no baseline population count for the walrus exists…. “We don’t have any evidence of declines,” even if declines are suspected, he said. [Reuters]
Leatherback turtles are the wandering type, undertaking far-flung ocean migrations of thousands of miles. What scientists who follow these long-lived creatures didn’t know, though, was just how many different routes they travel, and how far they journey before returning home. These are critical pieces of information for protecting the turtles, whose numbers are dropping. So Matthew Witt says he and his international team affixed trackers to the turtles and revealed the routes of their great sea voyages:
“What we’ve shown is that there are three clear migration routes as they head back to feeding grounds after breeding in Gabon, although the numbers adopting each strategy varied each year. We don’t know what influences that choice yet, but we do know these are truly remarkable journeys.” [The Guardian]
Gabon, in West Africa, is the home base for this largest breeding group of leatherbacks—it’s where they nest and lay their eggs. Witt’s team tracked 25 female turtles, all of whom followed one of those three general routes: out to the middle of the Atlantic and then back, down the African coast to the temperate South, or even all the way across the ocean to South America.
One female was tracked making a 7,563 kilometer (4,699 mile) journey traveling in a straight line across the South Atlantic from Africa to South America, said [Witt]. At a pace of 50 kilometers a day, that trip took about 150 days of consistent swimming, he said. [AP]
The continued onslaught by white nose syndrome against North America’s bats is one of the stories of the year—number 13, in fact, on DISCOVER’s Top 100 of 2010. But some help soon could be on the way in the form of Endangered Species Act protection. Earlier this month, a group of conservationists and scientists filed an emergency petition with the United States Fish and Wildlife Service to list the little brown bat under the act.
Emergency listing for a species does happen, but not very often, says Ann Froschauer, national white-nose syndrome communications leader for FWS. “Given the urgency of white-nose syndrome and recent information about predicted declines in little brown bat populations, the Service is committed to quickly reviewing scientific information, both published and provided by organizations such as these, in assessing the status of little brown bats and other bat species affected by WNS.” [Scientific American]
Listing the bats as endangered could force government action to protect them, including increased funding and the designation of critical habitat.
Polar bears, the poster-species for climate change, have been the subject of reports about new or growing threats in 2010: One story noted that the warming Arctic is pushing grizzlies north into polar bear territory, while another questioned whether polar bears can change their diet as their icy habitat melts. But the journal Nature this week brought an antidote to all that doom and gloom. A study modeling the Arctic climate suggests that it’s still not too late to protect the polar bear habitat, and therefore save the polar bear. The world just needs to reduce its greenhouse gas emissions.
The question is one of tipping points: Is the total demise of the Arctic summer sea ice already inevitable, or could a slowing of emissions also slow down the ice loss?
The dramatic retreat of Arctic sea ice in the summer of2007 prompted some researchers to warn that the system may have reached a tipping point that would lead to the disappearance of summer sea ice within the next several decades, regardless of actions humans took to reduce greenhouse-gas emissions. That concern, in turn, helped elevate the polar bear to climate-icon status and reportedly fed into then-President George W. Bush’s decision in 2008 to list the bear as “threatened” under the Endangered Species Act. The new study, however, finds no “tipping point” now or in this century in Arctic sea-ice decline, but rather a relatively steady fall-off in ice extent as average temperatures increase. [Christian Science Monitor]
Study author Steven Amstrup, formerly of the U.S. Geological Survey and now at Polar Bears International, modeled five different scenarios for greenhouse emissions in the future. He saw a linear relationship between rising temperatures brought on by those emissions and the retreat of Arctic ice. What he didn’t see was a sharp sudden drop, a point at which crossing some temperature boundary led to an irrevocable disappearance of the ice that would doom the bears.
The buzzwords of the week in Moscow are tiger and conservation.
Sunday marked the opening of the worldwide tiger summit, which brought together high-level representatives from the 13 tiger-habitat countries, including Russia and China, to discuss the best plan to save the tigers. The meeting goes through Wednesday.
Only about 3,200 tigers remain in the wild, and without help experts say populations will start to go extinct in less than 20 years.
“Here’s a species that’s literally on the brink of extinction,” said Jim Leape, director general of conservation group WWF. “This is the first time that world leaders have come together to focus on saving a single species, and this is a unique opportunity to mobilise the political will that’s required in saving the tiger.” [BBC News]
The working plan includes provisions to decrease poaching and smuggling of the tigers and calls for more protected habitats. Researchers say that if tigers are left alone and provided with enough habitat and prey, the population could double in 12 years.
The clock is suddenly ticking for the U.S. Department of the Interior to defend its classification of the polar bear as “threatened,” rather than the more protective “endangered” classification.
The “threatened” designation dates back to the George W. Bush administration, but in response to a series of lawsuits concerning the polar bear, U.S. District of Columbia District Judge Emmet Sullivan said this week that the government needs to review that decision, because it was not based on a proper reading of the Endangered Species Act.
In his decision, Judge Sullivan said that the agency was wrong to conclude that a species had to be in imminent danger of extinction in order to qualify as an endangered species. He said that the Endangered Species Act was ambiguous as to whether a species had to be on the brink of extinction in order to be considered endangered. He did not rule on the merits. [Wall Street Journal]
We know things are bad for biodiversity. But just how bad across the board? The scientists at the International Union for Conservation of Nature, as they will from time to time, just updated their Red List—an accounting of how much trouble vertebrate species face. According to them, one in five around the world is threatened, and the numbers are worse for groups like sharks and amphibians.
The survey results, which are coming out in the journal Science, are based on research conducted in nearly 40 countries. The 174 scientists studied about 25,000 species to estimate the condition of the approximately 56,000 species on the Red List. From IUCN’s release:
“The ‘backbone’ of biodiversity is being eroded,”says the emminent American ecologist and writer Professor Edward O. Wilson, at Harvard University. “One small step up the Red List is one giant leap forward towards extinction. This is just a small window on the global losses currently taking place.”
The Florida panthers may be saved. They simply needed a little Lone Star assist.
Fifteen years ago the big cats in Florida were in dire straits, doomed to probable extinction because of genetic inbreeding and dwindling numbers. Now, though, their population is on the upswing, thanks to a program that brought in eight females from a panther population in Texas to bolster the Florida cats. Scientists who studied the experiment report in the journal Science that it has worked: Both the numbers and the genetic diversity of Florida panthers improved drastically.
Hybrids of the Florida cats and cousins of the same species from a wild-caught Texas population have twice the genetic variety and far fewer of the genetic defects that were known in Floridian panthers before the introduction, says geneticist [and study coauthor] Warren Johnson. [Science News]
In August, Conservation International launched its globe-spanning search for amphibians that haven’t been seen in decades, but still could exist. This month, they’ve tracked down their first three slippery specimens. Scientists turned up two long-lost African frogs and a salamander from Mexico.
“It’s pretty extraordinary to think about just how long it has been since these animals were last seen,” observed project co-ordinator Robin Moore of Conservation International (CI). “The last time that the Mexican salamander was seen, Glenn Miller was one of the world’s biggest stars. The Omaniundu reed frog disappeared the year that Sony sold its first ever Walkman.” [BBC News]
The three rediscovered animals are:
The Mount Nimba reed frog (right). Last seen in 1967, it lives in the Ivory Coast. A local scientist spotted it.
The find was made “in a swampy field in Danipleu, an Ivorian village near the Liberia border.” [MSNBC]
Omaniundu Reed Frog (top). The most recently seen of the three, Omaniundu was last noted in 1979. It lives in the Democratic Republic of the Congo. According to Conservation International’s account of the rediscovery: (more…)
Of all the tigers left in the world—and there aren’t many—70 percent of them are clustered into lands that make up just 6 percent of the total tiger habitat in the world. Save these spots, scientists say today, and you save the tigers.
In the journal PLoS Biology, a large group of researchers outline why their 6 percent solution could succeed where other conservation attempts have failed. Basically, they say, efforts to save the cat have been ambitious, but too broad. Job one has to be the protection of these 42 small “source sites” in Asia (seen on the map in the slideshow above), that are home to the core population of tigers.
“The long-term goal is to conserve an Asia-wide network of large landscapes where tigers can flourish,” said Nigel Leader-Williams from Cambridge University, one of the scientists on this study. “The immediate priority, however, must be to ensure that the few breeding populations still in existence can be protected and monitored. Without this, all other efforts are bound to fail.” [BBC News]
80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles on the day's most compelling topics.
80beats is written by Veronique Greenwood and Valerie Ross. This team darts through each day's science news faster than the ruby-throated hummingbird that beats its wings 80 times per second. Send ideas, tips, suggestions, and complaints to [azeeberg at discovermagazine dot com].