Thursday 30 November 2017

A horse is a horse, of course, of course -- except when it isn't


Analysis of ancient DNA reveals a previously unrecognized genus of extinct horses that once roamed North America

Date:  November 28, 2017
Source:  University of California - Santa Cruz

Summary:
Scientists have discovered a previously unrecognized genus of extinct horses that roamed North America during the last ice age. The new findings are based on an analysis of ancient DNA from fossils of the enigmatic 'New World stilt-legged horse' excavated from sites such as Natural Trap Cave in Wyoming, Gypsum Cave in Nevada, and the Klondike goldfields of Canada's Yukon Territory.


There's a deeper fish in the sea


Date:  November 28, 2017
Source:  University of Washington

Summary:
The ocean's deepest fish doesn't look like it could survive in harsh conditions thousands of feet below the surface. Instead of giant teeth and a menacing frame, the fishes that roam in the deepest parts of the ocean are small, translucent, bereft of scales -- and highly adept at living where few other organisms can. A new fish species, the deepest in the ocean, was just discovered.


Why predators have such crazy faces


By Michael PriceNov. 29, 2017 , 2:05 PM

The eyes of the spectacled bear sit in disks of black fur on a stark white face. The African civet sports a necklace of dark and light bands. And hundreds of other mammalian predators have their own unique facial and chest markings that scientists have struggled to explain. Now, a new study is helping unravel some of the mystery.

Prey animals develop spots and stripes on their bodies to blend in with their environments and avoid detection; think the zebra. Many predators do, too, but even those without body camouflage still sport patterns on their face and chest, suggesting the markings aren’t all about blending in.




Invasive frogs give invasive birds a boost in Hawaii



Date: November 29, 2017
Source: American Ornithological Society Publications Office

Summary:
Puerto Rican coqui frogs were accidentally introduced to Hawaii in the 1980s, and today there are as many as 91,000 frogs per hectare in some locations. What does that mean for native wildlife? Concerns that ravenous coquis could reduce the food available for the islands' native insect-eating birds, many of which are already declining, spurred researchers to examine the relationship between frog and bird populations -- but their results weren't what they expected.

Monday 27 November 2017

Bacterium in a beetle makes it a leaf-eater


The specialized diet of a beetle is largely due to bacteria that live inside the insect

Date:  November 16, 2017
Source:  Emory Health Sciences

Summary:
A leaf-eating beetle has evolved a symbiotic relationship that allows the insect to break down pectin. The findings on the novel function of the bacterium, which has a surprisingly tiny genome -- much smaller than previous reports on the minimum size required for an organism not subsisting within a host cell.

Texas to Propose Ending Unlimited Commercial Wild Turtle Trapping – via Herp Digest

Nationwide Efforts to Ban Unsustainable Reptile Collection Gain Momentum 
For Immediate Release, November 15, 2017
Contact:  Jenny Loda, (510) 844-7136, jloda@biologicaldiversity.org   

AUSTIN, Texas— In response to a petition filed by the Center for Biological Diversity and several Texas-based conservation organizations, the Texas Parks and Wildlife Department on Tuesday agreed to propose a rule ending unlimited commercial trapping of the state’s wild turtles. 
“We’re so grateful these badly needed protections for Texas’ rare, native turtles are moving forward,” said Jenny Loda, a Center attorney and biologist who works to protect vulnerable reptiles and amphibians. “A few for-profit collectors shouldn’t be allowed to put the state’s turtles at risk of extinction. We’re hopeful the Texas Parks and Wildlife Commission will do the right thing and ban this harmful turtle trade.” 
Texas is the latest in a list of states to ban or propose ending commercial reptile collection that includes New York, Missouri and Nevada. 
Under current Texas law, unlimited collection of four native, freshwater turtle species is allowed on private property: common snapping turtles, red-eared sliders, smooth softshells and spiny softshells. 
Texas modified its regulations in 2007 to protect freshwater turtles from collection on its public lands and waters. But this only resulted in protections for turtles in 2.2 percent of the water bodies in Texas. Recent studies concluded that current turtle collection in Texas is likely not sustainable.
The Parks and Wildlife Department’s response to the conservation organizations’ petition came in a letter to the Texas Parks and Wildlife Commissioners. In it, the department’s executive director, Carter Smith, wrote that a review of the petition, along with scientific literature and the department’s own data, led to the conclusion that “there is sufficient scientific justification at this time to proceed to rulemaking to end the unlimited commercial collection of freshwater turtles.” 
The department’s letter says turtles are “[a]mong the nongame species of greatest concern” and are “highly sensitive to population alterations.” Department staff plans to propose a rulemaking at a future commission meeting.
“This is great news for Texas’s freshwater turtles and for all of us who care about the health of the state’s rivers,” said Tom Goynes, president of the Texas Rivers Protection Association. “Commercial trapping is devastating to turtle populations that are already suffering from multiple other threats, including habitat loss, water pollution and vehicular collisions.”
Millions of turtles classified as wild-caught are exported from the United States every year to supply food and medicinal markets in Asia, where native turtle populations have already been depleted by soaring consumption. Because turtles bioaccumulate toxins from prey and burrow in contaminated sediment, turtle meat is often laced with mercury, PCBs and pesticides, posing a health risk. Adult turtles are also taken from the wild to breed hatchlings for the international pet trade.
“The future of Texas turtles is now in the hands of the Department of Parks and Wildlife and wildlife commissioners,” said Loda. “We’re pleased the department is taking this step toward restricting commercial turtle collection. We urge the commission to fully and finally protect these animals as an invaluable part of state ecosystems.”
The petition that spurred Tuesday’s action was submitted earlier this year by the Center for Biological Diversity, Sierra Club's Lone Star Chapter, Texas Rivers Protection Association and Texas Snake Initiative.
Background
As part of a 
campaign to protect turtles in the United States, the Center for Biological Diversity has been petitioning states that allow unrestricted commercial turtle collection to improve their regulations. Last month, in response to a Center petition, the Missouri Department of Conservation proposed a ban on unlimited commercial collection of the state’s wild freshwater turtles. In September, Nevada created a statewide ban on the destructive commercial collection of all reptiles and New York halted all commercial terrapin turtle harvesting.
Before that, in March, Iowa adopted new regulations setting closed seasons and possession limits for commercial turtle trappers. In 2012 Georgia approved state rules regulating the commercial collection of turtles, and Alabama completely banned commercial collection. And in 2009 Florida responded by banning almost all commercial collection of freshwater turtles from public and private waters.
Texas is in a regional hotspot for commercial turtle collectors, and reform is needed. If the state created closed seasons and bag limits within its borders, adjacent states would likely follow its example; the region would be better equipped to protect its turtle populations by making clear to turtle traders that trade is strictly regulated and enforced. 
The Center recently petitioned for a ban on unlimited commercial trapping in ArkansasLouisiana and Oklahoma, three states that share a border with Texas.

A genus of European paper wasps revised for the first time using integrative taxonomy


Date:  November 13, 2017
Source:  Pensoft Publishers

Summary:
The European and Mediterranean species of the paper wasp genus Polistes were recently revised. For the first time for this group, scientists applied an integrative taxonomic approach which combines traditional morphological methods with DNA barcoding. As a result, the researchers were able to identify a new species from Morocco.

The European and Mediterranean species of the paper wasp genus Polistes were recently revised by scientists at the SNSB-Zoologische Staatssammlung München (ZSM).

For the first time for this group scientists applied an integrative taxonomic approach which combines traditional morphological methods with modern DNA barcoding.

As a result, the researchers were able to identify a new species from Morocco. For this well-researched wasp group, this is an actual sensation.

The study is published in the open access journal ZooKeys.

The Munich researchers analysed more than 260 wasp specimens collected from across the study area with the help of DNA barcoding.

They managed to identify all species and determine their distribution. In addition, based on the genetic data, they were able to evaluate morphological characters for each species and created a completely new key for identification.

The wasps of the genus Polistes belong to the family Vespidae. The genus is represented by 17 species in Europe and the Mediterranean, with four species occurring in Germany. Within the genus, 13 species are social, with the queen overwintering and founding a new nest with up to 200 workers. Four species are parasitic and have no workers.


Seals, birds and humans compete for fish in the Baltic Sea


Date:  November 13, 2017
Source:  Stockholm University

In Sweden and in other parts of Europe there are concerns that seals and birds compete with humans for fish resources. For the Baltic Sea, an international study now shows that this competition is a reality.

"Because fish is nutrient-rich food and angling provides valuable recreation, the increased populations of seals and fish-eating birds in the Baltic have resulted in a sometimes contentious debate over the effects of these animals on the fish stocks. The debates are often based on assumptions, which is why I took the initiative to look at the problem from a scientific viewpoint," said Sture Hansson, Professor of Ecology, Environment and Plant Sciences at Stockholm University.

Together with four researchers from the Swedish University of Agricultural Sciences (SLU) and seven other colleagues from countries around the Baltic, Hansson has estimated birds' and seals' fish consumption. Seals are the primary fish-eating mammals, and their consumption is about the same as that of all birds together. Humans catch 3 to 4 times more fish than seals and birds combined.

Small-scale coastal fishing most impacted by wildlife
The fishing grounds most impacted by competition from wildlife are the coastal areas with species like perch, pike, pikeperch, brown trout, salmon, whitefish and vendace. Seals and cormorants consume similar amounts as humans. Because we know that these fish are impacted by human fishing activities, it's reasonable to conclude that they are also impacted by predation from seals and birds. Wildlife thus competes with humans for these fish resources.


Sunday 26 November 2017

Old World monkeys could be key to a new, powerful rheumatoid arthritis therapy


Peptide only found in Old World monkeys has the potential to stop rheumatoid arthritis progression better than established treatments

Date:  November 16, 2017
Source:  University of Southern California - Health Sciences

In the quest for a new and more effective treatment for rheumatoid arthritis, researchers from the Keck School of Medicine of USC looked to a primate that mostly roams the land in Asia, the Middle East and Africa. It was a particular peptide only found in Old World monkeys, called θ-defensin 1 (RTD-1), that the researchers believed had the potential to stop -- or even reverse -- the progression of rheumatoid arthritis, an autoimmune disease that affects about 1.5 million people in the United States. The promising results of their study were published in PLOS ONE.

"RTD-1 is the prototype of a family of small cyclic peptides (θ-defensins), the only circular proteins in the animal kingdom," says study author Michael Selsted, MD, PhD, chair and professor of pathology at the Keck School. "Previous studies have shown that RTD-1 modulates lethal inflammation in animal models of infection, and we predicted that RTD-1's protective mechanism in those models would translate to rheumatoid arthritis, a disease in which chronic inflammation produces irreversible joint damage."

Flower attracts insects by pretending to be a mushroom


Date:  November 15, 2017
Source:  Kobe University

The mysterious flowers of Aspidistra elatior are found on the southern Japanese island of Kuroshima. Until recently, scientists thought that A. elatior has the most unusual pollination ecology among all flowering plants, being pollinated by slugs and amphipods. However, direct observation of their ecosystem has revealed that they are mainly pollinated by fungus gnats, probably thanks to their resemblance to mushrooms.


'Left-handed' fish and asymmetrical brains


Date:  November 15, 2017
Source:  University of Konstanz

To humans, being right-handed or left-handed plays an important role. The majority favours the right side of their bodies, while only about three per cent of people innately use both hands equally well. Preferring one side of the body over another is not unique to humans: the phenomenon occurs in the animal kingdom as well, for instance in great apes or birds, although their "handedness" is typically not as obvious as it is in humans. "Handedness" is particularly pronounced in cichlid fish of the species Perissodus microlepis, which is endemic to Lake Tanganyika in Africa.



Biology’s beloved amphibian — the axolotl — is racing towards extinction- Although abundant in captivity, the salamander has nearly disappeared from its natural habitat, and that’s a problem. – via Herp Digest

NATURE NEWS FEATURE  by Erik Vance, 11/15/17

Axolotls inhabit thousands of labs and home aquariums around the world, but are vanishing from their natural habitat.Credit: Brett Gundlock for Nature

When biologist Luis Zambrano began his career in the late 1990s, he pictured himself working miles from civilization, maybe discovering new species in some hidden corner of Mexico’s Yucatán Peninsula. Instead, in 2003, he found himself counting amphibians in the polluted, murky canals of Mexico City’s Xochimilco district. The job had its advantages: he was working minutes from his home and studying the axolotl (Ambystoma mexicanum), a national icon in Mexico and arguably the world’s most recognizable salamander. But in that first year, Zambrano couldn’t wait for it to be over.

“Let me tell you, I hated the project at the beginning,” he says. For one thing, “I couldn’t catch anything”.

Over time, however, he did catch some axolotls. What he found surprised him — and changed the course of his career. In 1998, the first robust study to count axolotls estimated that there were about 6,000 of them per square kilometre in Xochimilco1. Zambrano — who now is a professor at the National Autonomous University of Mexico (UNAM) in Mexico City — discovered in 2000 that the number had dropped to about 1,000 animals per square kilometre. By 2008, it was down to 100; today, thanks to pollution and invasive predators, there are fewer than 35 animals per square kilometre1. 

The axolotl is on the brink of annihilation in the canals of Mexico City, its only natural habitat. But although there might be just a few hundred individuals left in the wild, tens of thousands can be found in home aquariums and research laboratories around the world. They are bred so widely in captivity that certain restaurants in Japan even serve them up deep-fried

“The axolotl is a complete conservation paradox,” says Richard Griffiths, an ecologist at the University of Kent in Canterbury, UK, who recruited Zambrano to the project. “Because it’s probably the most widely distributed amphibian around the world in pet shops and labs, and yet it’s almost extinct in the wild.” 

This creates a problem for biologists. Thanks to its unique physiology and remarkable ability to regenerate severed limbs, the axolotl has become an important lab model for everything from tissue repair to development and cancer. But after centuries of inbreeding, captive populations are vulnerable to disease. And the loss of genetic diversity in wild axolotls — owing to their diminishing population — means that scientists lose out on learning all they can about the animal’s biology. 

As lab scientists continue to study the captive animal and its large and complex genome, Zambrano and a handful of other researchers are doing their best to preserve the wild version. They are breeding and releasing axolotls into control ponds and canals in and around Xochimilco to see how they fare, and hopefully to retain some of their natural genetic diversity. The task of saving them is difficult, but should be doable given the animal’s hardiness — if the Mexican government would only engage with the process.

“I’ve seen that in other places in the world, these kinds of huge tasks are possible,” Zambrano says. “If they can do it, why can’t we?”


Axolotls evolved relatively recently compared to other salamander species in the region, and they thrived along the banks of Lake Texcoco in the mountains of central Mexico. They are neotenic, meaning that the adults retain traits seen only in juveniles of similar species. Although other salamanders metamorphose into terrestrial creatures, axolotls hold on to their feathery gills and stay in the water for their entire lives. It’s as if they never grow up.

Sometime in the thirteenth century, Lake Texcoco was settled by the Mexica (the people that Europeans dubbed Aztecs). They built a powerful empire controlled by an island city built in the middle of the lake. As the empire grew, so did the land, expanding much faster after the Spanish conquest in 1521. Today, all that remains of the axolotl’s habitat are about 170 kilometres of canals criss-crossing Xochimilco, a district in the southern part of Mexico City (see maps at https://www.nature.com/articles/d41586-017-05921-w).

The species might have perished entirely under colonial rule, except that its odd inability to grow up caught the attention of European scientists, who puzzled over it in the late nineteenth century. 

Visitors to Mexico brought the creatures back and began breeding them. The animal turned out to be ideal for research: it reproduces readily in the lab, is a hardy survivor and is easy to care for. Axolotls have large cells that simplify investigations into development. Their eggs are almost 30 times larger than a human’s. And in an axolotl embryo, the neural plate cells — a precursor to the brain and spinal cord — are almost 600 times larger by volume. 

Also, the pigmentation of axolotls varies greatly from one cell to the next, unlike in humans or other animals, in which cell traits tend to be uniform. This can help researchers to track which tissues in an embryo become which organs. Yet it has a large genome — roughly ten times the size of a human’s — which can make it challenging to study in some respects.

“It is not a good genetic model organism, but it does regenerate — and that makes it an awesome biological model,” says David Gardiner, a developmental biologist at the University of California, Irvine, who has studied axolotl regeneration for decades. 

In the early twentieth century, axolotls were central to understanding how organs develop and function in vertebrates. They helped scientists to unpick the causes of spina bifida in humans — a birth defect in which the spine doesn’t form properly. And they played a part in the discovery of thyroid hormones: in the 1920s, scientists fed thyroid tissue from livestock to axolotls. If the tissue had been secreting hormone, the axolotls would metamorphose, losing their gills and shedding their larval skin.

In the 1980s, axolotls helped scientists to develop a model explaining how cells take on different forms in embryos. The ‘cell state splitter’ model proposes that many stem cells turn into specific tissues in the body through waves of pulling and stretching as embryos. Scientists found that they could watch the axolotl’s cells squeeze and stretch before they formed tissues. More recently, in 2011, extract from axolotl oocytes has been used to stop breast-cancer cells multiplying by switching on a tumour-suppressor gene2.

But perhaps the most fascinating contribution of the axolotl to science has been in regenerative medicine. The animals can grow back missing limbs, tails, organs, parts of the eye and even portions of the brain. Many scientists have presumed this is because, being neotenic, they retain some trait from their embryonic stages, although other salamanders seem to regenerate even as adults. 

Biologists have been trying to identify the mechanisms behind their regenerative abilities for decades, says Tatiana Sandoval Guzmán, a regeneration researcher at the Technical University of Dresden, Germany. “How do they do it? What is it that they have that we don’t? Or maybe the opposite — what in mammals is stopping that?”

Sandoval Guzmán is interested in bone and muscle regeneration and has taken over a long-standing axolotl laboratory in Dresden. A Mexican national who went to school not far from Xochimilco, she never thought much about the animal and certainly never considered studying it until she came to Germany. Today she is fascinated by the creature, and has shown3 that many of the mechanisms in axolotl regeneration — such as those involving muscle-tissue stem cells — are not so different from those found in humans.

Most regeneration research focuses on the stub — or blastema — that forms over the wound of a severed limb. Whereas such a wound in humans gets covered with skin tissue, axolotls transform nearby cells into stem cells and recruit others from farther away to gather near the injury. There, the cells begin forming bones, skin and veins in almost the same way as when the animal was developing inside the egg. Each tissue contributes its own stem cells to the effort. 
Researchers showed that a protein called transforming growth factor-β is key both in axolotl regeneration and in preventing scar tissue in injured human embryos during the first trimester. Adult mice and humans can regenerate digit tips, although humans lose this ability with age, suggesting that regenerative abilities could be reawakened in mammals. 

“There will be a day when we as humans can regenerate,” says Gardiner. His studies are not focused on rebuilding limbs, but on curing paralysis, growing healthy organs and even reversing ageing by repairing damaged and worn-out tissues. “And when they write that story, it will go back to these model organisms,” he says.

By the time that day comes, however, the wild axolotl may be gone. That worries Gardiner and Sandoval Guzmán because the animals that they study, like many lab animals, are highly inbred. Scientists use an ‘inbreeding coefficient’ to measure how small a gene pool is. Identical twins have a coefficient of 100%; totally unrelated individuals would score close to zero. A score above 12% indicates a population in which individuals are mostly breeding with their first cousins, and is considered a serious concern by ecologists and geneticists. The famously inbred and unhealthy Spanish Habsburg kings of the seventeenth century often had a coefficient somewhere above 20%. The average axolotl inbreeding coefficient is 35%. 
“These animals that we have, they still work just fine, they regenerate just fine. But they are so inbred. It’s a bottleneck,” Gardiner says. “Populations are very vulnerable to disease when inbred.” 

Their high level of inbreeding is partly a result of the bizarre historical path captive axolotls have taken. Most laboratory specimens trace their heritage back to a single group of 34 animals that were taken out of Xochimilco by a French-funded expedition in 1863. They sparked an axolotl-breeding craze across Europe by museums and naturalists.

In 1935, some of the animals travelled from a Polish laboratory back to North America, where they eventually became a breeding stock at the University of Buffalo, New York. Here, scientists brought in a series of wild axolotls to mix up the gene pool and at one point even added in tiger salamanders (Ambystoma tigrinum). The Buffalo population thrived and eventually moved to the University of Kentucky in Lexington, which is now the centre of global axolotl breeding. This means that, in addition to being inbred, almost all of the axolotls in labs and aquariums today are actually part tiger salamander. 

“They got bottlenecked in Europe for sure and then they got bottlenecked again,” says Randal Voss, head of the programme in Kentucky, which holds some 2,000 adults and 3,000–5,000 larvae. 

Voss says that axolotl research today is expanding throughout the world, thanks to modern genetics and stem-cell research. In 2015, he and his group published an initial assembly of the axolotl genome4, a Herculean task given its large size, estimated to be about 32 billion bases. But it is incomplete — the size and complexity of the genome proved too much for the computational power Voss’s group could throw at it. Scientists in several centres continue to work on completing the picture. 

But as they work on that, the creature’s vulnerability to disease has already caused mysterious massive die-offs in Voss’ facility. Scientists worry that if a new infectious disease were to race around labs worldwide, it might force them to abandon the axolotl, potentially setting research back by years. 

What’s more, no one can be sure that lab axolotls haven’t already diverged so much from their wild counterparts that they have lost key elements of regeneration. “Going back to study the wild population can give you a different mechanism or different genes,” says Sandoval Guzmán. “Losing the genetic diversity — of course it’s a loss for science.” 

“I can’t always know for sure, but the axolotls from Kentucky do have some differences,” says Arturo Vergara Iglesias, staring into a tank of axolotls lazily crawling about. “They have a lot of malformations. For example, they often have too many fingers.”

Vergara Iglesias is a biologist at the Centre for Biological and Aquaculture Research (CIBAC), an axolotl breeding facility near Xochimilco that is hoping to preserve a few wild lines. On the side, he breeds his own wild axolotls to sell to labs and pet distributors. He is standing over a salamander tank on a traditional Xochimilco farm plot, or chinampa, that is used as an educational facility for tourists. These animals, and the others he sells, were bred from a group of 32 pulled out of the water not far from the plot. In Mexico, the axolotl is a prized pet and a source of national pride. It’s the subject of countless Mexican memes and souvenirs, and is even the official emoji for Mexico City.

It’s hard to know exactly how many axolotls are left in the wild there. Zambrano guesses that during his last survey, in 2014, there were fewer than 1,000 in total, and perhaps fewer than 500. But he can’t be more specific — in the past two years, he’s been unable to raise the money to do any follow-up studies. That he can’t obtain funding for a simple census does not bode well for conservation efforts.


Students supervised by biologist Luis Zambrano release an axolotl into a protected pond near the National Autonomous University of Mexico in Mexico City. Credit: Brett Gundlock for Nature


Zambrano says that to save the wild axolotl, policymakers must address its two primary threats. The first is non-native fish such as the common carp (Cyprinus carpio) and tilapia (Oreochromis niloticus). Ironically, these were introduced to Xochimilco in the 1970s and 1980s through programmes run by the Food and Agriculture Organization of the United Nations, with the aim of getting more protein into local diets. Zambrano says he has mapped the areas where axolotls still remain; he envisions a team of local fishers being paid to sweep them of fish on an ongoing basis. Although this wouldn’t remove all the fish, for a few hundred thousand dollars it might give the salamanders a window in which to re-establish themselves. His work has shown that axolotls are most vulnerable to carp when they are at the egg stage, and to tilapia when they are juveniles, but reveals that if they can grow beyond a certain size, they might still thrive5.

The second threat is trickier. Every time a powerful storm fills the city’s ageing sewer system, treatment facilities release human waste into Xochimilco, carrying with it ammonia, heavy metals and untold other toxic chemicals. Amphibians, which breathe in part through their highly permeable skin, are vulnerable to these regular pollution dumps. It’s a testament to the animal’s resilience that it exists in the wild at all. 
These are complex issues, but they are not unsolvable. So far, however, there have been no efforts to save the wild axolotl beyond a few halfhearted outreach programmes and some photo opportunities. In 2013, CIBAC released a few thousand axolotls for a behavioural study; some of them survived and even seemed to breed the following year. This suggests that lab-bred salamanders might be able to thrive in the wild if they are raised in captivity to a certain size. But biologists caution that this doesn’t mean Mexico should start releasing them into canals. 

“There’s probably not much point in doing releases into the wild until you can neutralize the threats,” says Griffiths. “You just might be increasing the fish population by just chucking out more fish food.”

When Griffiths first started working in Xochimilco in 2000, his plan was to create a breeding programme aimed at releasing axolotls into the wild. But he and his Mexican partners quickly abandoned the idea once they saw the condition of the ecosystem, which was polluted and teeming with predators. It seemed pointless to send axolotls off to their deaths. Successful reintroductions, such as those of the pool frog (Pelophylax lessonae) in Britain or the hellbender salamander (Cryptobranchus alleganiensis) in the United States, require managing the ecosystem as a whole and working with the community. 

“If we had a million dollars per year for ten years, we would save Xochimilco. Which is nothing compared with the amount of money that is spent in this city,” says Zambrano.

One afternoon in October, Zambrano and a group of volunteers gather by the ponds near the UNAM campus to release ten lab-raised wild axolotls into a protected pond. If the animals survive and breed, they might someday act as a sort of genetic bank for the organism. Zambrano has been sporadically releasing and tracking animals here over two years to understand their behaviour and habitat preferences. His work so far suggests that the salamanders prefer fairly dirty ponds over the most pristine ones — another sign that axolotls might still thrive in Xochimilco if other pressures are removed. Similarly, CIBAC is breeding wild-type animals in an effort to preserve the axolotl’s genetic diversity. But if axolotls do not have a suitable home, most researchers say that their extinction in the wild might be inevitable, no matter what they do. 


“I would be frustrated if I saw it in that way,” says Zambrano. “I see it with another view — that I am doing my best to keep that from happening.”

Chimps make an extra effort to warn their oblivious friends when deadly snakes are nearby - via Herp Digest

by Alessandra Potenza Nov 15, 2017, Verge
                 


A chimp in Uganda’s Budongo Forest sees the fake snake. Video: Taï Chimpanzee Project

Chimpanzees live in dense forests filled with poisonous snakes and other threats — but luckily, they’ve got each other’s backs.

New research shows that when chimpanzees see a poisonous snake, they make an extra effort to alert other chimps that are unaware of the danger by making alarm calls and pointing out the location of the snake by gazing at it. That suggests that chimps communicate — and cooperate — with each other in more complex ways than previously thought possible.

Previous studies have shown that chimps warn others of danger, and are more likely to stop making alarm calls after the other chimps have climbed to safety. But today’s study, published in Science Advances, goes an extra step: it shows that chimps change their behavior — and adapt their alarm calls — based on whether the other chimps are aware of the danger. In other words, chimps take other animals’ perspective into account when communicating. And that’s pretty much what people do: when we talk, we consider what information is available to others.

“There seems to be more going on in chimpanzee communication — and possibly in other animal communication, especially the vocalization part — than has been assumed possible before,” says study co-author Catherine Crockford, a researcher at the Max Planck Institute for Evolutionary Anthropology.

Crockford got the idea for her research while spending hours in Uganda’s Budongo Forest, and observing chimps alerting each other of poisonous snakes. First, she and her team created fake snakes out of chicken wire and plaster that resembled deadly gaboon and rhinoceros vipers. “They were convincing enough to scare our field assistants,” she says. The researchers then placed the fake snakes where chimpanzees were expected to pass by, setting up a video camera to record their reactions. One-third of the animals were observed alarm calling other chimps in their group; then they indicated the snake’s position by gazing back and forth from the snake to the other chimps, continuing to do this until the others had seen the snake.

In a second experiment, the researchers also played prerecorded calls — either an alarm hoo or a rest hoo. The two calls influenced how the chimps reacted: those that had heard the rest call a few seconds before coming across the fake snake — which suggested that a nearby group member was unaware of the snake — gave more warnings, making more alarm calls and using body language. The findings suggest that when a chimp thinks its fellows don’t know about the danger, the chimp will make an extra effort to make sure they’re informed. In other words, its vocalizations seem to change based on what the other chimps know or don’t know.

The findings add to our understanding of how animals communicate with each other. They also tell us a bit about human evolution: it suggests that relatively complex forms of communication may have emerged before humans developed a language. “I think it helps us learn much more about ourselves, how our brains work,” Crockford says. And perhaps even more about how we interact with each other.


The chimps in the study were found to give more warnings about the snake if the other chimps were friends or kins. “They really have these strong friendships,” Crockford says. These friendships help individuals thrive: chimps and other primates who are more socially connected are found to have more offspring, Crockford says. “The motivation to keep friends [safe], to stop them being taken away by others, probably occupies quite a lot of their day and their brain work,” she says. “It’s a really crucial part of survival.”

Friday 24 November 2017

Ever Seen a Shark Walk? Tiny Animals Amaze on PBS


By Stephanie Pappas, Live Science Contributor | November 17, 2017 01:16pm ET

Great Whites may get all the headlines, but it's a miniature species of shark that can do what no other shark can: walk.

The epaulette shark (Hemiscyllium ocellatum) grows to less than 3.3 feet (1 meter) in length and lives in shallow coral reefs off Australia, Indonesia and New Guinea. With its small body and brown-spotted skin, the shark doesn't seem very flashy. But the species is well-adapted to its shallow marine environment. If a receding tide strands the animal on the reef, not only can the shark slow its metabolism to survive for an hour on a single gasp of air, but it can also use its fins to "walk" back into the water.

A new documentary by PBS called "Nature's Miniature Miracles" shows the sharks doing just that. The 1-hour show, part of the channel's "Nature" series, will feature feats by planet Earth's small, often-overlooked creatures. Viewers can watch epaulette sharks escape suffocation on dry land, see a peacock spider (Maratus Volans) do a colorful mating dance and peek in on a Japanese puffer fish as it sculpts a mating nest out of sand with its fins. [Photos: Pufferfish Make Seafloor Circles to Mate]



Chester Zoo successfully breeds rare Catalan newt


Twelve Montseny newts – one of world’s rarest amphibians - hatched as part of joint breeding project with Catalan authorities

Stacee Smith
Friday 17 November 2017 15.06 GMTLast modified on Friday 17 November 2017 15.50 GMT

Conservationists at Chester Zoo have successfully bred one of the world’s rarest amphibians – the Catalan newt – in an attempt to save it from extinction.

The zoo is the first organisation outside Catalonia to become involved in the breeding project for the newt, the rarest amphibian in Europe.

The critically endangered species, also known as the wild Montseny newt, is from the Montseny mountain range in north-eastern Catalonia, about 60 miles (100km) north of Barcelona.

The recovery plan is a joint effort between Chester Zoo, the Barcelona provincial council, the Catalan government and Barcelona Zoo.

As part of the plan, 12 Montseny newts have hatched at Chester Zoo, where a team of experts are working to ensure their continued survival before they are released into the wild.

Experts at Chester have created a purpose-built breeding facility for the newts, away from all other amphibians housed at the zoo to ensure their bio-security.

In parallel with the breeding programme, conservation efforts are also being made to improve the newts’ natural habitat in preparation for their reintroduction – including improving the water quality and ecological flow of the streams they live in.


‘Eight, nine, ten …’ Why people are counting sheep in Cheddar Gorge


The audit of a feral flock at the Somerset beauty spot is significant

Sunday 19 November 2017 00.04 GMT

There is a shaggy creation myth surrounding the feral sheep of Cheddar Gorge in Somerset. The story goes that during a poker game in the village in 1992 one of the gamblers, running out of money, put his seven sheep up as his stake. He lost, so the winner took the animals home and put them in his garden. The next morning the winner’s wife looked out of her window to see the new arrivals eating the garden ... and the sheep had to go.

Where they went is what draws 35 people to a layby in the chilly morning shadow of Cheddar Gorge. The winner of the two rams and five ewes deposited them on the craggy hillside there a quarter of a century ago, where they have been ever since – the seven becoming 10, becoming 50, then within five years 100 and now, well, who knows?

Hence the annual sheep count organised by the National Trust – an attempt to quantify one of England’s only flocks of feral sheep. There are feral goats in the gorge too, but ownerless sheep are something of a rarity.

Soay sheep, the variety roaming free in the gorge, are smaller than regular ones, are typically chocolate coloured, still have their tails and have the distinction of being self-shedding. But to know all that, you need first to be able to find them.

Dr David Bullock, leader of the count and the Trust’s head of nature conservation, herds together the counters, a mixture of staffers, volunteers and students in land management and agriculture from the nearby Bridgwater and Taunton College.


11 Animals That Have Been Wiped Off This Planet, Because [of] Humans!


NOVEMBER 19, 2017
   
Since time immemorial, human beings have hunted down animals and messed with the environment for their own ease and comfort. We might consider ourselves the most evolved species on this planet, but we have used our 'superior skills' to satiate our selfish ends, all at the cost of wiping out entire species of animals  from the face of the Earth.

Here are 11 species that our future generations will never see because of our selfishness.

1.  Great Auk
The great auk ( Pinguinus impennis ) was a flightless coastal bird that  lived on rocky islands around the North Atlantic, including in Canada, Greenland, Iceland, the British Isles and Scandinavia.

Up until the late 18th century, they were hunted down in huge numbers. The rare birds soon became a prized specimen for collectors and they were driven to extinction by the mid-1850s.  The killing of the last mating pair happened on July 3, 1844, by Sigurour Isleifsson and two other men who had been hired by a merchant to hunt the birds.

2. Dodo
The dodos belonged to the pigeon and dove family and were native to the island of Mauritius. Back in 1598, Dutch travellers were the first to discover this unique species. Dodo's laid only one egg a year and with the onset of human invasion, their survival came under major threat.

The importing of dogs, cats, pigs, rats and crab-eating macaques is what really killed the species. The bird eventually faded into oblivion, so much so that “dead as a dodo” and “to go the way of the dodo” are two famous phrases inspired by the death of the species.

3. Elephant Bird
The Elephant Bird, (Aepyornis), was the largest bird that ever lived. At 10-foot-tall, this 1,000-pound behemoth once roamed the island of Madagascar.  Related to ostriches and emus, the elephant bird evolved at a time when birds ruled the earth and had existed for 60 million years.  But thanks to humans, the bird was hunted into extinction.

4.Thylacines (Tasmanian Tigers)
The Tasmanian Tiger was an incredibly unique species. It had the head of a dog, stripes of a cat and the pouch of a kangaroo. Their killing  started after farmers complained about their livestock going missing, and the only way out was to exterminate them on a large scale.

Parasitic plants rely on unusual method to spread their seeds


November 14, 2017

Three species of non-photosynthetic plants rely mainly on camel crickets to disperse their seeds, according to new research from Project Associate Professor Suetsugu Kenji (Kobe University Graduate School of Science). These findings were published on November 9 in the online edition of New Phytologist.

Most non-photosynthetic plants have very small seeds that can be dispersed by the wind like dust particles. However, some achlorophyllous plants grow in the dark understory of forests, and have abandoned the dependence on the wind for seed dispersal. In this study, Professor Suetsugu investigated the seed dispersal method for three such plants: Yoania amagiensis, Monotropastrum humile and Phacellanthus tubiflorus. He identified the camel cricket as their main seed disperser, the first evidence of camel crickets being used for seed dispersal in the flowering plants.

The most famous example of insect carriers is ants, but the ants do not eat the seeds: they carry them to their nests in their mandibles. Insects who carry seeds by eating them are very rare. One example is the New Zealand weta, but this is a special case: normally this role would be taken by mammals, but in New Zealand the only native mammals are bats.

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