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« Reply #600 on: Dec 16, 2014, 08:56 AM »

Unique New Worm Species Has Reversed Its Own Evolution

December 14, 2014
Chuck Bednar for redOrbit.com – Your Universe Online

An unusual, newly discovered type deep-sea worm lives on the bones of dead animals and features males that have grown significantly larger than their predecessors, researchers from the Scripps Institution of Oceanography report in a new study.

According to San Francisco Chronicle science editor David Perlman, the authors of the new Current Biology paper detailing the discovery report that the worms have reversed their own course of evolution like no other creature before. Not only have they grown larger than their forebears, they mate in vastly different ways than their closest relatives.

The worms were initially discovered on the remains of a long-drowned seal at the bottom of Monterey Bay, some 3,000 feet below the surface, by marine biologist Greg Rouse during expeditions above the mile-deep Monterey Canyon and off the Oregon coast. The species, which has been named Osedax priapus, is the second known species of the bone-consuming Osedax worms discovered (the first came in 2002).

Monterey Bay Aquarium Research Institute (MBARI) evolutionary biologist Robert Vrijenhoek, who captained the research vessel used by Rouse during the new discovery, was also responsible for the previous find. At the time, he indicated that the creatures had no mouth, stomach, legs or eyes. However, the body of each of the females held hundreds of males that were so small, they resembled larvae and lived on small bits of the female’s eggs.

Rouse told Perlman that the new worms, which were named in honor of the mythological god of fertility, were an “evolutionary oddity unlike any other in the animal kingdom.” The males are now as large as the females and tens of thousands of times larger than the other species, he explained, and instead of surviving on scraps inside the opposite sex of the species, they were witnessed devouring the same rotting bones as the females.

“This worm was weird enough as it was and now it’s even weirder,” Rouse said, according to the website Sci-News.com. “This shows us that there continue to be mysteries in the sea and there is still so much more to discover, especially since we only found these creatures 12 years ago.”

The mating process of Osedax priapus was also found to be vastly different than its predecessors. While the earlier type of Osedax males are permanently attached to their female hosts, the new species have to seek out a mate. To account for this, the males have evolved to have an extremely extendable body that allows them to reach far out (up to ten times its contracted state) to find female mating partners, Dr. Rouse explained.

Luis Georg of Perfect Science noted that the new worms were found at largely the same area of Monterey Bay that the previous species had been found 12 years ago. They are members of Siboglinidae, a family of worms that are also known as bearded worms and that live in unexpected locations, such as hot and acidic hydrothermal sea vents.

However, Vrijenhoek told Perlman that this new species “is exceptional because the genes for producing full-size adult males should have deteriorated over time because they weren’t used by the dwarf males. But apparently the genes are still there. And although those microscopic dwarf males weren’t competing with the females for food, in this much larger species they do.”

“So it’s our hypothesis that here there’s a new potential for sexual conflict, and the ability of the males to stretch themselves out like rubber bands to roam for females suggests that they’ve reinvented mating,” he added. “It’s a throwback to an earlier ancestral species more than 40 million years ago. We’re continuing to collect more species to see what their genes are telling us.”

Click to watch: https://www.youtube.com/watch?v=XGlTBl4iUwc


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« Reply #601 on: Dec 17, 2014, 06:31 AM »

Barbaric capture of baby elephants for zoos in China shocks the world

The Guardian
16 Dec 2014 at 17:22 ET   

Are there no limits to the cruelty that humans are prepared to inflict on their fellow creatures in the natural world? When there is money to be made, apparently not

In a recent article for the BBC , George Monbiot quotes the words of the pioneering conservationist Aldo Leopold: “One of the penalties of an ecological education is that one lives alone in a world of wounds.” These words have a particular resonance to those of us engaged in what sometimes seems a losing battle to save the world’s dwindling populations of elephants, rhinos, and other large mammals.

In a developing scandal, the Zimbabwe Parks and Wildlife Management Authority (ZPWMA) has reportedly captured several dozen baby elephants for export to zoos in China and possibly also the Middle East.

According to Zimbabwe Conservations Taskforce director Johnny Rodrigues, the elephants are between two-and-a-half and five years old and are being sent under conditions of tight security by container trucks to Maputo in Mozambique for transfer to a livestock sea freighter bound for China.

In a further twist it is reported that Australian Hank Jenkin, a former top official from CITES, which is supposed to regulate the global trade in endangered species, is now working as a consultant to procure “hundreds” of elephants for Chinese zoos and safari parks. Sadly, this is not the first report I have heard of the supposed gamekeepers of CITES turning poachers.

Are these baby elephants “ivory orphans” taken as they stand grieving at the bloody corpses of their mothers and sisters? Or were they dragged forcibly from their mothers, or stolen away in the night? We do not know.

But whatever the circumstances of their capture we can hardly imagine the physical and emotional torment these animals will suffer: confined, alone and frightened on the long voyage to China.

Elephants are among the most intensely social of all large mammals. Elephant mothers suckle their young for five years, which means that many of the elephants bound for China, some as young as two-and-a-half years old, were not physically prepared to be separated from their mothers.

But the emotional bond between mother and offspring lasts much longer. Elephant researcher George Wittemyer reports how a female elephant is still intimately bonded with her ten year old daughter. Bonds between sisters can be just as strong: Juvenile female African elephants are often fascinated with newborn calves; they help out in caring for them, and will even suckle them.

Adult elephants form deep bonds with each other, which last for decades. According to Cynthia Moss, founder of the world’s longest running elephant research project at Amboseli , these bonds play a vital role transmitting communicating social and ecological knowledge from one generation to another.

Elephants take care of the sick and comfort the dying. The film Echo tells the story of Eli who was born deformed and survives because of the love and attention he gets from his mother and sisters who would not leave him behind.

My own research has involved decades of delight in getting to know elephants – and discovering that it is a two-way street: the elephants get to know me as well. They remember the looks, smells and sounds of researchers. And even now, I am still continuously surprised by their intelligence and thoughtfulness.

Recently I watched 66 year old grandmother Barbara guard her sleeping granddaughter from the feet of playful youngsters, then position her body to cast a shade from the scorching sun. The group could not move on until the 5 day old baby had rested.

To call these behaviours “almost human” only reveals the unlimited arrogance of our own species. Scientists can study elephant behaviour, and we can all marvel at it. But we can never know, and cannot even begin to imagine the profound underlying emotional and spiritual bonds among elephants.

If you think the baby elephants in the photos look sweet, you cannot imagine just how sweet they look to a mother elephant, or the anguish she feels when her calf is stolen from her.

Zimbabwean officials have defended their actions by saying that the export of live elephants is not illegal. It should be. Thankfully many countries around the world are now taking action to prohibit elephants from being held in zoos and circuses. But China stands apart from this wave of change and seems to be going backwards.

Likewise, Zimbabwe’s actions ignore lessons that have been learned long ago in other countries. The practice of taking baby elephants, once common in South Africa, was banned there when the results of research in Kenya were presented to the authorities and convinced them of the horrific psychological suffering and trauma involved.

The driving spirit behind Zimbabwe’s actions may well be President Mugabe, who is on record on more than one occasion as saying that Zimbabwe’s wildlife “needs to start paying dividends”. Another top official put it more bluntly: “We are not interested in wildlife… we want cash.”

As a counter-argument, conservationists often point out that the most profitable use of wildlife is to leave it where it is, where it can generate sustainable incomes from wildlife tourism.

I have made these arguments myself, and will no doubt continue to do so. But as I reflect on the plight of these baby elephants and the suffering of their families, I ask myself: why do we have to commoditise the natural wonders of our planet?

Why can we not simply live and let live, and be content with the privilege of sharing our world with these marvellous fellow creatures?

It is sometimes said that elephants are like humans. Maybe. But what is certain is that we humans need to learn to be more like elephants.

guardian.co.uk © Guardian News and Media 2014

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« Reply #602 on: Dec 20, 2014, 08:01 AM »

Wolves, bears, lynxes rebounding in Europe

Despite the continent's high population density, large carnivores are staging a comeback in Europe, researchers say.

By Stephanie Pappas, LiveScience December 19, 2014
The Christian Science Monitor   

Despite having half the land area of the contiguous United States and double the population density, Europe is home to twice as many wolves as the U.S.

A new study finds that Europe's other large carnivores are experiencing a resurgence in their numbers, too — and mostly in nonprotected areas where the animals coexist alongside humans. The success is owed to cross-border cooperation, strong regulations and a public attitude that brings wildlife into the fold with human society, rather than banishing it to the wilderness, according to study leader Guillaume Chapron, a professor at the Swedish University of Agricultural Sciences' Grimsö Wildlife Research Station.

In Europe, "we don't have unspoiled, untouched areas," Chapron told Live Science. "But what is interesting is, that does not mean we do not have carnivores. Au contraire; we have many carnivores."
Europe's carnivores bounce back

Chapron and his colleagues pulled together data from all over Europe — excluding Russia, Ukraine and Belarus — on the population numbers of brown bears (Ursus arctos), Eurasian lynx (Lynx lynx), wolverines (Gulo gulo) and gray wolves (Canis lupus). Their results, published today (Dec. 18) in the journal Science, reveal that large carnivores in Europe are doing very well.

With the exception of Belgium, Denmark, the Netherlands and Luxembourg, every European country in the study has a permanent and reproducing population of at least one of the four large carnivores, the researchers reported. The continent is home to 17,000 brown bears in 10 populations spread over 22 countries. There are 9,000 lynx in 11 populations in 23 countries. Wolves are thriving, with more than 12,000 individuals found in 10 populations in 28 countries.

Wolverines can live only in the cold climates of Scandinavia, so Norway, Sweden and Finland are the only countries in the study that host all four of Europe's major large carnivore species. There are two populations of wolverines in Europe, with an estimated total of 1,250 individuals. (However, wolverines do face threats from climate change, due to their cold-dependent lifestyles.)

Some small populations of carnivores are in decline across Europe, the researchers noted, but none of the large to medium populations are suffering.

Attitudes toward the wild

What makes this success so surprising is that these wolves, bears, lynx and wolverines are surviving largely outside of protected areas.

"Maybe the wolf is your black bear," Chapron said, explaining European attitudes toward the animal. In the United States, he said, wolves are seen as animals that can't coexist with humans, whereas black bears are generally tolerated in residential areas, with locals making accommodations such as bear-proof trash cans.

Chapron acknowledged that there are clashes in Europe between carnivores and people, particularly around livestock farming. Traditional strategies — such as employing livestock-guarding dogs or shepherds, or corralling livestock in pens at night — help ease carnivore attacks on valuable livestock, and compensating farmers for losses can also help mitigate problems, he said.

"There is a need to keep the conflict at a low intensity," Chapron said.

Chapron also credited the Habitats Directive, a set of conservation regulations that protects species and habitat types across national borders, for keeping carnivores from decline and extinction.

"We have found a recipe that works," he said.

Whether a similar recipe could work in the United States depends on public attitudes. However, the European model clearly shows that large carnivores can coexist with people in places Americans tend to find unimaginable, Chapron said. In 2011, a male gray wolf traveled from Oregon to California, becoming the first wolf in the state since 1924. (He later trotted back across the border to Oregon, and fathered pups.)

The appearance of the wolf triggered debate over how to manage the return of wolves in California. That is a matter of public policy, but Chapron pointed out that there is a fast-growing wolf population in Germany and Poland, where roads are as dense as anywhere in the world.

"If people from California decide to have wolves," he said, "then the European model clearly shows that you can have plenty of wolves in California."


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« Reply #603 on: Dec 20, 2014, 08:06 AM »


Wipe Out: History's Most Mysterious Extinctions

Joseph Castro, LiveScience Contributor 

Mysterious Wipe-Outs

<p>What do the dinosaurs, the dodo bird and the Tasmanian tiger all have in common? They're all extinct. Countless species have come and gone in the history of our planet, some leaving more of a mark than others. Sometimes the cause of a species' extinction is unknown. To understand and explain these deaths, scientists often work with numerous hypotheses and constantly hunt for more data to unravel the mysteries.</p> <p>From the fearsome megalodon to the awkward elephant bird, here are some of history's most puzzling extinctions.</p>

Rocky Mountain Locust

<p>When thinking about extinctions, dinosaurs, dodos and other large creatures typically come to mind. But insects can also disappear — and in a relatively short amount of time, too. Between 1873 and 1877, huge swarms of the Rocky Mountain locust (Melanoplus spretus) reportedly caused hundreds of millions of dollars in damage as they ravaged crops throughout the Midwestern United States. Less than 30 years later they were extinct.</p> <p>So what happened? Many theories point to large-scale environmental changes, such as the disappearance of the buffalo and their locust-breeding wallow habitats. But evidence suggests that innumerable locust eggs may have succumbed to plowing and irrigation used by the very farmers the insects terrorized. Some scientists think that the lack of genetic variation may have added to the locusts' troubles.</p>

Megalodon

<p>Between 28 million and 1.5 million years ago, megalodon ruled Earth&#39;s oceans. This terrifyingly large shark, which dined on giant whales with its 7-inch-long (18 cm) teeth, reached a maximum length of over 60 feet and weighed as much as 100 tons. For comparison, great white sharks &mdash; megalodon&#39;s closest living relative &mdash; rarely reach the 20-foot (6 m) mark.</p> <p>So what could cause a monster at the top of the food chain to sputter out of existence? Theories abound. One idea posits that megalodon couldn&#39;t handle the oceanic cooling and sea level drops that came with the ice ages of the late Pliocene and early Pleistocene epochs. On the other hand, another explanation ties the shark&#39;s demise to the disappearance of the giant whales it fed on.</p>

Woolly Mammoth

<p>For 250,000 years, the woolly mammoth (Mammuthus primigenius) enjoyed an expansive range that covered parts of North America, Europe and Asia. A small population survived on Wrangel Island in the Arctic Ocean until 3700 years ago, while the rest of the hairy giants disappeared from their Siberian habitat some 10,000 years ago.</p> <p>A long-standing theory proposes that early humans hunted the woolly mammoth to extinction. On the other hand, some scientists believe a global shift toward freezing temperatures did the beasts in. But perhaps no single culprit should be blamed. A study detailed online June 12, 2012, in the journal Nature Communications claims that a combination of factorscontributed to the mammoth&#39;s downfall.</p>

Broad-Faced Potoroo

<p>After Europeans settled Australia a few hundred years ago, the country suffered many species&#39; extinctions. Some creatures declined due to land-clearing practices; others suffered because of the predatory red fox, which was initially introduced to Australia in the mid-1800s for hunting purposes. However, the broad-faced potoroo (Potorous platyops) appears to have taken a severe hit before the settlers arrived &mdash; an unusual occurrence among recently extinct Australian species.</p> <p>Researchers collected the last few specimens of the broad-faced potoroo &mdash; a marsupial less than 10 inches long around 1875. It&#39;s unknown how long the animals survived after that. It&#39;s also not clear what finally pushed the marsupials over the edge, but studies suggest predation by feral cats, which likely made it to the continent by way of Dutch shipwrecks in the 17 century, played a large role. [Marsupial Gallery: A Pouchful of Cute]</p>

Atelopus longirostris

<p>Atelopus longirostriswas a toad native to the humid forests of northern Ecuador. A. longirostris &mdash; named so for it&#39;s long snout &mdash;&nbsp;has not been recorded since 1989.</p> <p>The cause of the amphibian&#39;s extinction has not been determined, but scientists think chytridiomycosiswas certainly involved. In recent years, the disease chytridiomycosis, which is caused by the fungus Batrachochytrium dendrobatidis, has become world famous as a frog killer, boasting a 100 percent mortality rate for some amphibian species. Researchers think A. longirostris may have had to contend with climate change and habitat loss, in addition to the deadly disease.</p>

Elephant Bird

<p>The dodo may be the poster child for species extinction, but it&#39;s not the only flightless bird to bite the dust. Enter the elephant bird. Elephant birds &mdash;&nbsp;Madagascar natives consisting of at least four different species &mdash; are among the world&#39;s most massive birds. They were a towering 10 feet (3 m) tall and nearly 1,000 pounds, or 454 kilograms. (Note: male ostriches grow up to only 9 feet, or 2.7 m, tall.) Written records suggest the birds were around till at least the 17th century, and researchers think they were likely fully extinct by the early 18th century. &nbsp;</p> <p>There are two main theories explaining the elephant birds&#39; demise, both of which involve humans. Some researchers believe the birds fell to habitat loss and people stealing their eggs, which were 150 times the volume of a hen&rsquo;s egg. Others think diseases carried over from settlers&#39; chickens may have devastated the elephant bird populations.</p> <p>(Editor's Note: This entry was updated to correct the metric conversion for the bird's height.)</p>

Neanderthals

<p>No countdown about species extinctions is complete without mention of our hominid brethren, the Neanderthals. Why Neanderthals went extinct some 30,000 years ago is one of anthropology&#39;s greatest debates. At one point, scientists favored the idea that a &quot;volcanic winter&quot; &mdash;&nbsp;caused by a super-eruption combined with a sharp cold spell &mdash;&nbsp;killed the Neanderthals, who were unable to adapt to the climate change. But new research rules out the catastrophe hypothesis.</p> <p>The real Neanderthal killers, then, were likely anatomically modern humans. Even still, there&#39;s no singular explanation. Could early humans have committed genocide? Maybe they just outcompeted Neanderthals? Or perhaps contact with other hominids introduced pathogens Neanderthals couldn&#39;t fight? And then there&#39;s the most romantic hypothesis (which actually has some genetic evidence to back it up): Neanderthals interbred with early humansAnd that somehow led to their demise.</p>


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« Reply #604 on: Dec 20, 2014, 09:11 AM »


1st dog-adoption telethon helps lots of homeless hounds

More than 4 million people tuned in to “Cause for Paws: An All-Star Dog Spectacular,” which was co-hosted by actresses Hilary Swank and Jane Lynch, and aired on donated time from the Fox Network.

By SUE MANNING
The Associated Press
Karleigh Vroman / The Associated Press

LOS ANGELES — More than 4,400 people filed adoption papers for homeless dogs during what was billed as the first all-star dog-adoption telethon, producers say.

“If only half of those result in adoptions, that would be huge,” director Michael Levitt said.

Seventy dogs from rescues across the country were featured on the two-hour Thanksgiving night telecast, a show the producer sees becoming a fixture.

More than 4 million people tuned in to the show, which was co-hosted by actresses Hilary Swank and Jane Lynch, and aired on donated time from the Fox Network.

Besides the permanent homes offered, 250 people signed up as foster parents for homeless dogs, Levitt said.

Swank said for her, the magic of “Cause for Paws: An All-Star Dog Spectacular” was “watching the dream of saving hundreds of dogs turn into the reality that became thousands as the awareness was raised of the severe homeless-pet problem.”

She added the show was the best holiday gift she could receive.

“Knowing that lives were saved as people opened their hearts and homes to new four-legged family members warms my heart and touches my soul more than you can imagine,” Swank said.

Levitt said the goal was to educate people in an entertaining way and show them the joy that comes from rescuing animals.

“There was one amazing comment after another posted on social media, including people who posted pictures of dogs they went out and rescued because of the show,” the director said.

Singer-actress Miley Cyrus confirmed just three days before the show that she would be there, Levitt said. She agreed to do a segment on pit bulls, writing her own copy and doing her own research. It was a side of Cyrus some people have never seen, he said.

The director said he couldn’t imagine that there wouldn’t be more telethons because this one was so successful.

Viewers also donated more than $200,000 during the telethon that will be distributed to eligible rescues.

Some of the rescues represented on the telethon reported getting an additional 15,000 hits on their websites in the days after the telethon.


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« Reply #605 on: Today at 07:49 AM »

How we found world’s deepest fish in the Mariana Trench — and why we must keep exploring

The Conversation
20 Dec 2014 at 10:55 ET   

It was our 14th expedition to the trenches of the Pacific Ocean, where depths can exceed 10,000m. And it was due to be our last for the foreseeable future.

We had been aboard the Schmidt Ocean Institute’s (SOI) vessel RV Falkor for 30 days. It was almost over. Then, it turned out to be “the big one”.

For this was the expedition in which my colleagues and I discovered a snailfish living some eight kilometres below the waves, deeper than any fish we know of. My colleagues from the University of Hawaii even recovered some in their traps.

In the past six years we have made many discoveries in the depths, such as the missing order of Decapoda (shrimps) that were long thought absent from the trenches but are actually rather conspicuous.

In the Kermadec Trench off New Zealand we found the “supergiant” amphipod, a crustacean 20 times larger than its shallow-sea relatives. We also filmed large numbers of tadpole-like snailfish in multiple trenches, and as deep as 7700m in the Japan Trench.

Snailfish surprise

Based on these observations we predicted that when exploring the Mariana Trench – the world’s deepest – we would find the the Mariana’s own personal snailfish, probably living between 6500m and around 7500m, with more being found at the deeper end of that range.

Exploring the Mariana Trench. The record-breaking fish appears at 1:45: https://www.youtube.com/watch?v=6N4xmNGeCVU

We also predicted that we would see the decapods and supergiants in the upper depths of the trench, and right enough there they were.

A device used to gather samples of ocean floor had an inspection camera on it to monitor the equipment. One night after a dive to 7900m when watching the footage coming back in, a strange ethereal little fish swam past. That got our eyebrows raised. It looked like a snailfish, but was extremely fragile (even for a snailfish) and had a very distinctive appearance.

This prompted a case of “game on”, to find it again, and sure enough we did. The deepest we found it was at 8145m, nearly 500m deeper than our personal record from the Japan Trench.

This of course means that our predictions were slightly wrong, but also makes it very exciting: there are still fish, and perhaps other things, down there to discover and this is what drives us to do more. Our work at the deepest place on Earth is not done yet.

Why we need to keep exploring

As much as we are excited about finds such as these, we are typically chased up by people who ask “why do we bother?”, and add rather deflating comments such as “what benefit does this have to society?”

In response I explain that such exploration benefits responsible stewardship of the oceans. In the long term, conservation and maintenance of the our seas relies on us really understanding the ocean – that is, the ocean in its entirety from the surface to what lies beneath the deepest seafloor. The anthropocentric opinion of “out of sight, out of mind” simply doesn’t cut it, and is sadly still common place.

The deep ocean is far deeper than a person can dive to or fish from, but that doesn’t mean that the things down there are of no consequence to society. We must not, however, confuse curiosity-driven exploration with the search for entertainment or stockpiling consumables.

We know that the deep sea is not exempt from a changing climate or man-made disturbances such as plastic pollution. The depths are intrinsically linked to processes in the upper ocean that we humans are continually meddling with.

Changes that happen in the upper ocean will have an effect on the largest habitat on Earth, yet people question why we study the deep sea. We say, how can we conserve the largest habitat on Earth if we know nothing about it? In the quest to understand the entire ocean, people have to study the shallow bits, the deepest bits and everything in-between.

By Alan Jamieson, University of Aberdeen

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« Reply #606 on: Today at 08:56 AM »

The Strange Tale of a New Species of Lizard

DEC. 18, 2014
Carl Zimmer
NYT

Each year, scientists publish roughly 17,000 detailed descriptions of newly discovered animals. Recently, in the journal Breviora, researchers described yet another, a new species of lizard called Aspidoscelis neavesi.

At first glance, this seems to be a run-of-the mill lizard: a small, slender creature with spots along its back and a bluish tail. In fact, Aspidoscelis neavesi is quite exceptional. The lizard was produced in the laboratory by mating two other species, and its creation defies conventional ideas about how new species evolve.

The evolution of a new animal species is usually a drawn-out affair. Typically, an existing animal population is somehow divided, and the newly isolated populations reproduce only among themselves. Over thousands of generations, the animals may become genetically distinct and can no longer interbreed.

Of course, scientists have long known that some related species sometimes interbreed. But the hybrid progeny generally were thought to be evolutionary dead-ends — sterile mules, for instance. In recent decades, however, researchers have learned that these hybrids may represent new species.

Some of the most striking examples occur among whiptail lizards, which live in the southwestern United States. In the 1960s, scientists noticed that some whiptail lizard species had a strange genetic makeup. They have two copies of each chromosome, just as we do, but each copy is very different from its counterpart. The genes look as if they come from different species.

Perhaps stranger, many species produce no males. The eggs of the females hatch healthy female clones, a process known as parthenogenesis.

Normally, unfertilized animal eggs have only one set of chromosomes. The second set is derived from a male’s sperm following fertilization. But parthenogenic female whiptail lizards can duplicate the chromosomes in their offspring without males.

These findings led scientists to a hypothesis for how these strange species came about: Sometimes individuals from two different species of whiptail lizards interbreed, and their hybrid offspring carry two different sets of chromosomes.

Somehow, this triggers a switch to parthenogenesis. The female hybrids start to produce clones distinct from either parental species. In other words, they instantly become a new species of their own.

But it gets even more bizarre. Some species of whiptail lizards carry three sets of genes, rather than two.

How can that be? Scientists hypothesized that male lizards from sexually reproducing species sometimes mated with parthenogenic females. Sometimes, their sperm succeeded in fertilizing a female’s eggs, which already contained two sets of chromosomes. The egg now had three sets, and voilà: yet another a new species.

The strangeness doesn’t end there. In 1967, a Harvard graduate student named William B. Neaves was searching for whiptails around Alamogordo, N.M., when he found one with four sets of chromosomes.

Dr. Neaves concluded that the lizard was a hybrid. Three sets of chromosomes appeared to have come from a species called Aspidoscelis exsanguis. The fourth set hailed from a species called Aspidoscelis inornata. Both species live around Alamogordo.

Dr. Neaves didn’t follow up on this finding, instead pursuing a career researching fertility and stem cells. But at a dinner in 2002, he mentioned the whiptail lizards to Peter Baumann, a molecular biologist at Stowers Institute for Medical Research, where Dr. Neaves served as president.

Dr. Baumann decided it was high time to use new scientific tools to study whiptail lizards, and he and Dr. Neaves started making road trips to New Mexico to catch them and take them back to Stowers. As they came to understand the biology of the lizards better, they and their colleagues began to bring different species together to see if they could hybridize. Most of the time, their experiments failed.

In 2008, the scientists tried to recreate the hybrid with four sets of chromosomes. They put female Aspidoscelis exsanguis (the parthenogenic species with three sets of chromosomes) and male Aspidoscelis inornata in the same containers. In short order, the lizards started mating, and the females laid eggs. When the eggs hatched, the scientists examined the genes of the baby lizards and found four sets of chromosomes.

Four of the new hybrids were females. To the delight of the scientists, the females could clone themselves — and the offspring could produce clones of their own. Today, the scientists have a colony of 200 of these lizards.

Eventually the scientists became convinced they had produced a new species. They ran the idea past Charles J. Cole, a herpetologist at the American Museum of Natural History, who has studied whiptail lizards since the 1960s.

“As soon as they told me what they had done, I knew it was a species,” Dr. Cole said. The lizard’s body was clearly distinct from its parental species, and the fact that the species emerged in a lab seems irrelevant to Dr. Cole.

“It’s not a Frankenstein genome manipulation,” he said. “It’s lizards in cages doing their thing.”

Dr. Cole agreed to help Dr. Baumann and his colleagues formally describe the new species. Dr. Cole carefully cataloged the many features, both striking and subtle, that set the new lizard apart from other known whiptail species. They named it Aspidoscelis neavesi to honor Dr. Neaves.

“These lizards should have their own species,” said Laurence M. Hardy, a biologist at Louisiana State University Shreveport, who was not involved in the study. He said that they fulfilled the formal requirements.

But David Hillis, an evolutionary biologist at the University of Texas, questioned whether any lineage of hybrid whiptail lizards should be considered true species. “It is widely practiced, but often questioned,” he said.

Traditionally, scientists have looked at how animals reproduce to decide if they truly represent a species or just a subspecies. Animals within a real species produce offspring mostly with one another. As a result, their genes mix together into a single gene pool.

Are these new lab lizards really a species? Aspidoscelis neavesi doesn’t need to mate at all. It doesn’t maintain a single gene pool. The mutations that one lizard acquires will be passed down only to her offspring, not to others.

Aspidoscelis neavesi also raises a special puzzle, Dr. Hillis noted, because it emerged over and over again. Dr. Baumann and his colleagues have now successfully produced fertile hybrids of Aspidoscelis inornata and Aspidoscelis exsanguis dozens of times from different parents. Since each lineage comes from different parents, they could arguably be considered separate species, not just a new one.

Dr. Hillis says he thinks biology needs a different way to describe these lizards. “I think they are better termed ‘hybrid clones,’ ” he said. “That would represent a more accurate reflection of their relationship to the tree of life.”

Dr. Baumann argues that giving the lizards a species name is important simply to help scientists communicate. “It allows them to know what they’re talking about,” he said.

He and his colleagues have a lot to talk about. They are investigating how Aspidoscelis neavesi copes with having four sets of chromosomes. In humans, extra chromosomes can cause dramatic changes. An extra copy of chromosome 21, for example, leads to Down syndrome.

Yet Aspidoscelis neavesi appears to be a perfectly healthy, normal group of lizards. “If anything, we see a slight advantage,” Dr. Baumann said.

The good health of Aspidoscelis neavesi raises yet another puzzling question: If the parental species of Aspidoscelis neavesi live near one another, shouldn’t Aspidoscelis neavesi exist in the wild, too?

It’s possible that healthy hybrids do emerge from time to time, but that they have been the victims of bad luck. “If you’re rare, you’re more likely to go extinct by chance,” said James Mallet, a Harvard biologist who was not involved in the study.

On the other hand, it may be that Aspidoscelis neavesi is thriving unseen around Alamogordo. Dr. Cole hopes that the new paper, with its detailed description of the new species’ appearance, will help people to identify them.

“They may be out there somewhere, and we just don’t know it yet,” said Dr. Cole.


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Ten years after ESA listing, killer whale numbers falling

Puget Sound’s already small killer-whale population has declined in the decade since it was protected under the Endangered Species Act. Some experts view the death this month of a pregnant female orca as an alarm bell for the region’s southern residents.

By Craig Welch
12/21/2014
Seattle Times environment reporter

The death of J32, the pregnant orca known as Rhapsody, is renewing concern among some scientists about the fate of the rest of Puget Sound's southern resident killer whales.

He’s trailed them and photographed them, mapped their family trees and counted their offspring, coming to identify individuals by their markings, sometimes even ascribing personalities based on behavior.

For much of the past 40 years, the dean of San Juan Island orca research has vacillated between hope and frustration about the future of Puget Sound’s southern resident killer whales.

But the death this month of J32, an 18-year-old orca known as Rhapsody — who was pregnant with a nearly full-term female calf — is pushing Ken Balcomb closer to despair.

“The death of this particular whale for me shows that we’re at a point in history where we need to wake up to what we have to consider: ‘Do we want whales or not?’ ” said Balcomb, with the Center for Whale Research.

With 2015 marking the 10th anniversary of the government’s decision to protect these orcas under the Endangered Species Act (ESA), the numbers certainly don’t look good.

The population of J, K and L pods has dropped from a high of 99 in 1995 to 77 this month — the lowest since 1985. No whale has successfully given birth in more than two years — a first in the decades since whales have been monitored. And the small number of female whales able and likely to give birth reduces the potential for a speedy rebound.

In fact scientists had hoped young J32, who was just coming into adulthood, would help turn that pattern around for decades to come.

“We’ve not only lost her, but we’ve lost all of her future reproductive potential, which will potentially have an impact on the population,” said Brad Hanson, killer-whale expert with the National Oceanic and Atmospheric Administration’s (NOAA) Northwest Fisheries Science Center. “That’s disconcerting.”

Even the apparent cause of J32’s demise — an infection spread by the death of her unborn calf — leads Balcomb to suspect the worst. He thinks the whales’ chief source of food, chinook salmon, is in such short supply that J32 relied on its own blubber, releasing stored contaminants that harmed her immune and reproductive systems.

But officials overseeing whale recovery say it’s too soon to say the situation is, in fact, dire. The root cause of the infection’s spread is not yet clear and may prove complex. It’s not known if the lack of successful new births is a trend or anomaly. And whale numbers have been lower than this before and bounced back, suggesting to some that there is room for optimism.

After all, said Will Stelle, West Coast administrator for NOAA Fisheries, Snake River sockeye runs were so depleted in 1992 that only one fish — known as Lonesome Larry — returned to spawn in Idaho’s Redfish Lake. This year, after decades of work by scientists, 1,600 fish returned, nearly 500 of which were naturally spawned.

“That’s not to say the issues around Snake River sockeye are the same — they’re not,” Stelle said. “But if you look in the rearview mirror, you’ll see that in fact over the last decade we’ve made substantial progress in building the basic foundation for a long-term conservation strategy for southern residents. We’re by no means there. But a decade ago we were in the dark ages.

“This is not the time to light our hair on fire, or to run about saying ‘The sky is falling, the sky is falling,’ ” he said. “What is really important here is to take the long view.”

But even Stelle agreed a central question remains: How much time do orcas have?

Salmon declines

J32 was born into a family where adult females tended to die early. She was the first and, presumably, only calf of a 15-year-old whale that died two years later. The matriarch of the family died a year after that at 37 — early for a species with a life span similar to humans.

But it’s a sad irony that this salmon-eating machine wound up dead in front of a chinook-fishing charter business in British Columbia.

Long before her carcass was towed ashore on the east side of Vancouver Island near Comox, B.C., early this month, scientists had begun to wrestle with the role salmon declines may be playing in whale survival.

“The reality is, the basic problem is food,” Balcomb said.

In the 1960s and 1970s, an orca population that a century earlier may have numbered anywhere from 140 to 200 was decimated by the aquarium trade. Entrepreneurs drove orcas into net pens in coves and sold them to marine parks around the globe until their numbers had plummeted to just 71 in 1974.

Only in the last 10 years have researchers truly documented their troubles.

“Since then we’ve improved our understanding of the individuals themselves, their population dynamics, their geographic distribution and diet and pollutant loading and contaminants and the effects of all that on productivity,” Stelle said.

But two of the whales’ three biggest problems — the buildup of pollutants such as DDT and polychlorinated biphenyls in their blubber, and disturbance by marine traffic — appear to be worsened by a third, a reduction in available prey.

These whales can eat sockeye and halibut, but overwhelmingly prefer fatty chinook from Puget Sound and Canada’s Fraser River, distinguishing them from other fish by using sonar to sense differences in the animals’ swim bladders. And Puget Sound chinook numbers have dropped to about 10 percent of their historic high. They, too, are listed for protection under the ESA.

When killer whales are hungry, research suggests they may metabolize poisons built up in their fat over years, and expend energy they can’t afford if they have to avoid disturbance from boats and other traffic.

Yet scientists continue to disagree on how much of a role that has ever played in any deaths. Few whales wash up dead for them to study. Among those that have, only one — Rhapsody’s uncle, J18 — offered clues that led some, but not all, to believe hunger was a factor in his death.

Government scientists certainly agree that a diminished food supply is a major issue. But they’re still running tests on J32’s organs, skin and fatty tissue to help narrow down her health issues more precisely.

“If southern residents are on a lower nutritional plane, then the effects of contaminants may be allowed to cause some sort of problem in a random way that disease events would be able to take over,” Hanson said. “But a lot of times what we’re seeing is these skinny animals and a lot of people say ‘these whales are starving to death.’ But it’s not that simple.”

For example, whales hunt in groups and sometimes share prey, and may give away food to others that they themselves could use.

Regardless of whether food availability helped trigger her death, government researchers share some of Balcomb’s concerns about the state of the population.

“It’s not so much that there are fewer reproductive-age females now than there used to be,” said NOAA whale scientist Mike Ford, “but rather that they may not be giving birth as often as expected.”

Deep concern

For Balcomb, the loss of J32 suggests it’s time to consider drastic measures, such as a ban or steep curtailment in chinook fishing, even though fishing is likely the least of the threats chinook face.

“It’s a wake-up call — we know what the problem is, whether it’s dams or fishing or habitat destruction,” he said. “It’s just what happens when millions of people move into the watershed. (But) stopping fishing, at least for a while, is something we can do immediately.”

Stelle, whose agency helps oversee chinook-harvest levels, said fishing has been curtailed already by about 30 percent in agreements with the Canadians, but he couldn’t conceive of a day when he’d seriously consider an outright ban, which would violate tribal-treaty rights. Still, he doesn’t rule out even more drastic cuts.

Stelle, like most experts, maintains that one of the hardest problems to address for orcas is controlling stormwater so even more contaminants aren’t flushed into the Sound, where they can work their way up the killer whale food chain. That is likely an expensive fix.

The other is reducing development in areas harmful to chinook survival — estuaries, floodplains, areas that alter drainage into river beds. But that problem is made ever more complex by the fact that dozens of government entities oversee all that decision-making.

“The particular challenges I think that are daunting can best be illustrated by driving south on I-5 and looking around,” he said. “That built-out landscape fundamentally poses the most significant challenge for us. It is: How do we reconcile the continued human-population growth projected for the basin with trying to rebuild the productivity of the most important habitats for orcas and their prey.”

Martha Kongsgaard, who leads the Puget Sound Partnership, a government agency charged with cleaning up the Sound, agreed J32’s death puts into relief just how much is at stake if the region doesn’t pick up the pace in tackling these problems.

“You don’t want to raise the alarm every time a whale dies, but I think we are really on the brink of possibly losing them,” she said. “And we ignore the orcas’ incredible totemic and symbolic power at our peril. They’re telling us it’s an emergency right now.”


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