The fossil findings, described in the March 26 issue of the Zoological Journal of the Linnean Society, represent the oldest evidence of these iconic tuxedo-clad seabirds in Africa, predating previously described fossils by 5 to 7 million years.

Co-authors Daniel Thomas of the National Museum of Natural History and Dan Ksepka of the National Evolutionary Synthesis Center happened upon the 10-12 million year old specimens in late 2010, while sifting through rock and sediment excavated from an industrial steel plant near Cape Town, South Africa.

Jumbled together with shark teeth and other fossils were 17 bone fragments that the researchers recognized as pieces of backbones, breastbones, wings and legs from several extinct species of penguins.

Only one penguin species lives in Africa today — the endangered black-footed penguin, or Spheniscus demersus. But newly found fossils confirm that as many as four penguin species coexisted on the continent in the past – Credit: Daniel Thomas

Based on their bones, these species spanned nearly the full size spectrum for penguins living today, ranging from a runty pint-sized penguin that stood just about a foot tall (0.3 m), to a towering species closer to three feet (0.9 m).

Only one penguin species lives in Africa today — the black-footed penguin, or Spheniscus demersus, also known as the jackass penguin for its loud donkey-like braying call. Exactly when penguin diversity in Africa started to plummet, and why, is still unclear.

Gaps in the fossil record make it difficult to determine whether the extinctions were sudden or gradual. “[Because we have fossils from only two time periods,] it’s like seeing two frames of a movie,” said co-author Daniel Ksepka. “We have a frame at five million years ago, and a frame at 10-12 million years ago, but there’s missing footage in between.”

Humans probably aren’t to blame, the researchers say, because by the time early modern humans arrived in South Africa, all but one of the continent’s penguins had already died out.

A more likely possibility is that rising and falling sea levels did them in by wiping out safe nesting sites.

Although penguins spend most of their lives swimming in the ocean, they rely on offshore islands near the coast to build their nests and raise their young. Land surface reconstructions suggest that five million years ago — when at least four penguin species still called Africa home — sea level on the South African coast was as much as 90 meters higher than it is today, swamping low-lying areas and turning the region into a network of islands. More islands meant more beaches where penguins could breed while staying safe from mainland predators.

But sea levels in the region are lower today. Once-isolated islands have been reconnected to the continent by newly exposed land bridges, which may have wiped out beach nesting sites and provided access to predators.

Although humans didn’t do previous penguins in Africa in, we’ll play a key role in shaping the fate of the one species that remains, the researchers add.

Numbers of black-footed penguins have declined by 80% in the last 50 years, and in 2010 the species was classified as endangered. The drop is largely due to oil spills and overfishing of sardines and anchovies — the black-footed penguin’s favorite food.

“There’s only one species left today, and it’s up to us to keep it safe,” Thomas said.

Source: National Evolutionary Synthesis Center (NESCent) via EurekAlert! [March 26, 2013]

The study, published online Feb. 26 in the Ecological Society of America’s scientific online journal Ecosphere, reveals leatherback nests at Jamursba Medi Beach in Papua Barat, Indonesia — which accounts for 75 percent of the total leatherback nesting in the western Pacific — have fallen from a peak of 14,455 in 1984 to a low of 1,532 in 2011. Less than 500 leatherbacks now nest at this site annually.

Thane Wibbels, Ph.D., a professor of reproductive biology at UAB and member of a research team that includes scientists from State University of Papua (UNIPA), the National Oceanic and Atmospheric Administration (NOAA), National Marine Fisheries Service and the World Wildlife Fund (WWF) Indonesia, says the largest marine turtle in the world could soon vanish.

“If the decline continues, within 20 years it will be difficult if not impossible for the leatherback to avoid extinction,” said Wibbels, who has studied marine turtles since 1980. “That means the number of turtles would be so low that the species could not make a comeback.

“The leatherback is one of the most intriguing animals in nature, and we are watching it head towards extinction in front of our eyes,” added Wibbels.

Leatherback turtles can grow to six feet long and weigh as much as 2,000 pounds. They are able to dive to depths of nearly 4,000 feet and can make trans-Pacific migrations from Indonesia to the U.S. Pacific coast and back again.

Biologists have found a 78 percent drop in leatherback turtle nests at their primary nesting site. There is concern that the largest marine turtle in world may vanish – Credit: UAB

While it is hard to imagine that a turtle so large and so durable can be on the verge of extinction, Ricardo Tapilatu, the research team’s lead scientist who is a Ph.D. student and Fulbright Scholar in the UAB Department of Biology, points to the leatherback’s trans-Pacific migration, where they face the prevalent danger of being caught and killed in fisheries.

“They can migrate more than 7,000 miles and travel through the territory of at least 20 countries, so this is a complex international problem,” Tapilatu said. “It is extremely difficult to comprehensively enforce fishing regulations throughout the Pacific.”

The team, along with paper co-author Peter Dutton, Ph.D., discovered thousands of nests laid during the boreal winter just a few kilometers away from the known nesting sites, but their excitement was short-lived.

“We were optimistic for this population when year round nesting was discovered in Wermon Beach, but we now have found out that nesting on that beach appears to be declining at a similar rate as Jamursba Medi,” said Dutton, head of the NOAA Southwest Fisheries Science Center’s Marine Turtle Genetics Program.

The study has used year-round surveys of leatherback turtle nesting areas since 2005, and it is the most extensive research on the species to date. The team identified four major problems facing leatherback turtles: nesting beach predators, such as pigs and dogs that were introduced to the island and eat the turtle eggs; rising sand temperatures that can kill the eggs or prevent the production of male hatchlings; the danger of being caught by fisheries during migrations; and harvesting of adults and eggs for food by islanders.

Tapilatu, a native of western Papua, Indonesia, has studied leatherback turtles and worked on their conservation since 2004. His efforts have been recognized by NOAA, and he will head the leatherback conservation program in Indonesia once he earns his doctorate from UAB and returns to Papua.

He has worked to educate locals and limit the harvesting of adults and eggs. His primary focus today is protecting the nesting females, eggs and hatchlings. A leatherback lays up to 10 nests each season, more than any other turtle species. Tapilatu is designing ways to optimize egg survival and hatchling production by limiting their exposure to predators and heat through an extensive beach management program.

“If we relocate the nests from the warmest portion of the beach to our egg hatcheries, and build shades for nests in other warm areas, then we will increase hatching success to 80 percent or more,” said Tapilatu.

“The international effort has attempted to develop a science-based nesting beach management plan by evaluating and addressing the factors that affect hatching success such as high sand temperatures, erosion, feral pig predation and relocating nests to maximize hatchling output,” said Manjula Tiwari, a researcher at NOAA’s Southwest Fisheries Science Center in La Jolla, Calif.

Wibbels, who is also the Ph.D. advisor for Tapilatu, says that optimizing hatchling production is a key component to leatherback survival, especially considering the limited number of hatchlings who survive to adulthood.

“Only one hatchling out of 1,000 makes it to adulthood, so taking out an adult makes a significant difference on the population,” Wibbels said. “It is essentially the same as killing 1,000 hatchlings.”

The research team believes that beach management will help to decrease the annual decline in the number of leatherback nests, but protection of the leatherbacks in waters throughout the Pacific is a prerequisite for their survival and recovery. Despite their prediction for leatherback extinction, the scientists are hopeful this species could begin rebounding over the next 20 years if effective management strategies are implemented.

Author: Kevin Storr | Source: University of Alabama at Birmingham [February 26, 2013]

Humans and rhesus macaques shared a common ancestor approximately 25 million years ago. Although there are now over seven billion humans on the planet only 100,000 years ago the human population was as low as one million. The effective human population, the number of people required to explain current genetic variation rate, was until recently less than 8,000.

The population size of rhesus macaques is in the millions and is exceeded only by humans (among primates). However there are 13 subspecies which have evolved to exploit environments as diverse as savannah and forests, and across a range of climate zones.

The rhesus macaque has three times as much genetic variation than humans – Credit: David Goldman

A team of researchers led by Christina Barr and David Goldman from the NIH determined that the effective population size for these primates was 80,000, ten times that of humans. Analysis of genetic variation, using single nucleotide polymorphisms (SNPs), showed that the macaque genome had three times higher genetic variation than humans. Most of these SNP were previously unknown and were disproportionally found in functionally important regions of DNA and each known gene had at least one SNP.

Dr. Goldman explained, “Although macaques have more variation than humans in the protein coding regions of genes, the ratio of variation in these regions compared to non-coding regions is significantly lower. Additionally the macaque variation is less likely to alter protein function. This brings down the amount of damaging variation to a level close to what was actually seen in humans.”

Dr Barr continued “Our comparative approach across primate species (human and macaques) gives us a genomic view of evolutionary selection and reaffirms the effects of population history on genetic variation. Not very long ago, on an evolutionary timescale, there were more macaques than people, and the genomes of both species are a legacy of those times past.”

Source: BioMed Central [June 29, 2012]

Life on Earth is divided into two main groups, the prokaryotes and the eukaryotes. Prokaryotes are simple life forms, with no membranes or cell nuclei; this group includes bacteria and archaea. Eukaryotes, which include humans, animals, plants, fungi and algae, have cell membranes and nuclei. This new organism is a eukaryote.

More specifically, it’s an algae-eating protozoan, a type of creature that have been known to science since the Civil War but which have lacked genetic studies because they’re difficult to culture. Researchers in Norway were able to harvest them from a lake bed and breed them in the lab. This one is called Collodictyon.

This strange protozoan has four flagella. The rest of the entire tree of life is divided by organisms that have either one or two flagella. UiO/MERG

Researchers led by Kamran Shalchian-Tabrizi, head of the Microbial Evolution Research Group (MERG) at the University of Oslo, were examining the species’ genes and morphological makeup and found it is not like anything else. It evolved a billion years ago, give or take a couple hundred million years. It could have been living the same way since then, providing scientists a glimpse of what the earliest life forms looked like.

The organism is weird in several key ways. It has four flagella, for instance, which makes it different from bacteria and eukaryotes. Mammals, fungi and amoebae only have one flagellum — that’s the propeller-like feature that helps cells move (think of the “tail” of a sperm cell). Algae, plants and single-celled parasites called excavates are thought to have had two flagella. Collodictyon is somewhere between an excavate and an amoeba.

Also, the organism has the same internal structure as a parasite, but it uses amoeba-like protuberances to catch its food, which are blue-green algae. So again, it combines features from two branches of the eukaryotes, further evidence that it’s a primordial creature, the researchers say.

Even at its highest levels, the tree of life is mutable — the domain archaea was only recognized in 1990. So it wouldn’t be out of the question for this organism to spark an entirely new kingdom. The research on Collodictyon is published in the journal Molecular Biology Evolution.

Source: Science Daily [April 30, 2012]

The tiny frog sits easily on a US dime, whose diameter is 18mm

At 7mm (0.27 inches) long, Paedophryne amauensis may be the world’s smallest vertebrate – the group that includes mammals, fish, birds and amphibians.

The researchers also found a slightly larger relative, Paedophryne swiftorum.

Presenting the new species in PLoS One journal, they suggest the frogs’ tiny scale is linked to their habitat, in leaf litter on the forest floor.

Finding the frogs was not an easy assignment.

What are amphibians? * First true amphibians evolved about 250 million years ago * Three orders: frogs (inc. toads), salamanders (inc. newts) and the limbless caecilians * Adapted to many aquatic and terrestrial habitats * Present on every continent except Antarctica * Many metamorphose from larvae to adults

The New Guinea forests are incredibly loud at night; and we were trying to record frog calls in the forest, and we were curious as to what these other sounds were," said research leader Chris Austin from Louisiana State University in Baton Rouge, US.

"So we triangulated to where these calls were coming from, and looked through the leaf litter.

"It was night, these things are incredibly small; so what we did after several frustrating attempts was to grab a whole handful of leaf litter and throw it inside a clear plastic bag.

"When we did so, we saw these incredibly tiny frogs hopping around," he told BBC News.

Littering the leaves

The Paedophryne genus was identified only recently, and consists of a number of tiny species found at various points in the eastern forests of Papua New Guinea.

The tiny limbs of amauensis (top) and swiftorum are rendered translucent

“They’re occupying the relatively thick leaf litter of tropical forest in low-lying parts of the island, eating incredibly small insects that typically are much smaller than insects that frogs eat,” said Professor Austin.

“And they’re probably prey for a large number of relatively small invertebrates that don’t usually prey on frogs.”

Predators may well include scorpions.

Intriguingly, other places in the world that also feature dense, moist leaf litter tend to possess such small frog species, indicating that amphibians are well placed to occupy this ecological niche.

Before the Paedophrynes were found, the title of “world’s smallest frog” was bestowed on the Brazilian gold frog (Brachycephalus didactylus) and its slightly larger Cuban relative, the Monte Iberia Eleuth (Eleutherodactylus iberia). They both measure less than 1cm long.

The smallest vertebrates have until now been fish.

Adult Paedocypris progenetica, which dwells in Indonesian swamps and streams, measure 7.9-10.3 mm long.

Male anglerfish of the species Photocorynus spiniceps are just over 6mm long. But they spend their lives fused to the much larger (50mm long) females, so whether they should count in this contest would be disputed.

Paedophryne amauensis adults average 7.7mm, which is why its discoverers believe it how holds the crown.

The remote expanses of Papua New Guinea rank alongside those of Madagascar as places where hitherto undiscovered amphibian species are expected to turn up, as they are largely undeveloped and not well explored.

Author:Richard Black| Source: bbc [January 12, 2012]

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NAIROBI, Kenya (AP) — The world’s newest snake has menacing-looking yellow and black scales, dull green eyes and two spiky horns. And it’s named after a 7-year-old girl.

Matilda’s Horned Viper was discovered in a small patch of southwest Tanzania about two years ago and was introduced last month as the world’s newest known snake species in an issue of Zootaxa.

Tim Davenport, the director of the Wildlife Conservation Society in Tanzania, was on the three-person team that discovered the viper. Thanks to his daughter, the snake will always carry a family namesake.

“My daughter, who was 5 at the time, became fascinated by it and used to love spending time watching it and helping us look after it,” Davenport told The Associated Press on Wednesday. “We called it Matilda’s Viper at that stage … and then the name stuck.”

Only three new vipers have been discovered across Africa the last three decades, making the find rare and important. The Wildlife Conservation Society is not revealing exactly where the snake lives so that trophy hunters can’t hunt it.

Davenport said he is not sure how many live in the wild because snake counts are hard to do. Twelve live in captivity and a breeding plan is being carried out.

Davenport, a Briton who has lived in Tanzania for 12 years, said that while many people fear snakes, most are harmless and help keep rodent numbers down. Matilda’s horned viper can grow to 2 feet (65 centimeters) or bigger, he said.

“This particular animal looks fierce and probably is venomous (though bush viper bites are not fatal),” Davenport told AP via an Internet chat. “However, it is actually very calm animal and not at all aggressive. I have handled one on a number of occasions.”

The Wildlife Conservation Society runs the Bronx Zoo and the Central Park Zoo in New York, and Davenport said it would be a “great option” to showcase the new horned viper at one of those locations, but that nothing has yet been decided.

Author: JASON STRAZIUSO | Source: news.yahoo [January 07, 2012]

The gorillas appear to be grooming him, as a fellow tourist videotapes the encounter.

“The silverback is just behind you. He’s sitting a meter behind you and [there are] three babies squashed between him and you. The female’s just behind you to your right,” the friend is heard saying. “Tell me what you’re feeling now, John.”

“I just feel like one of the gang,” John says. After several minutes, the troupe moves on. Park rangers say encounters such as this are rare.

Author: Jayne Clark | Source: USA Today [December 22, 2011]

“We have really sophisticated meteorological models for predicting climate change,” says ecologist Mark Urban, the study’s lead author. “But in real life, animals move around, they compete, they parasitize each other and they eat each other. The majority of our predictions don’t include these important interactions.”

Plenty of experimental studies have shown that species are already moving in response to climate change, says Urban, assistant professor of ecology and evolutionary biology at the University of Connecticut. For example, as temperatures rise over time, animals and plants that can’t take the heat are moving to higher altitudes where temperatures are cooler.

But not all species can disperse fast enough to get to these more suitable places before they die off, Urban says. And if they do make it to these better habitats, they may be outcompeted by the species that are already there – or the ones that got there first.

With coauthors Josh Tewksbury and Kimberly Sheldon of the University of Washington, Urban created a mathematical model that takes into account the varying rates of migration and the different intensities of competition seen in ecological communities. The goal was to predict just how successful species within these communities would be at shifting to completely new habitats.

Their results showed that animals and plants that can adjust to climate change will have a competitive advantage over those that don’t.

Animals with small geographic ranges, specific habitat needs and difficulty dispersing are likely to go extinct under climate change, their model shows. Further, these animals are more likely to be overrun by other species that can tolerate a wider range of habitats.

“When a species has a small range, it’s more likely to be outcompeted by others,” Urban says. “It’s not about how fast you can move, but how fast you move relative to your competitors.”

Urban likens this scenario to a train traveling up a mountain on a track. If each boxcar – representing a species – travels at the same speed, they will likely all reach the top eventually. But in reality, each car can move at a different speed, creating a collision course.

“There’s always a car in front of you and a car behind,” explains Urban. “When you introduce the ability to move at different speeds, they’re constantly bumping into one another, even running each other over. It’s a recipe for disaster.”

Importantly, the authors speculate that current predictions of biodiversity loss under climate change – many of which are used by conservations organizations and governments – could be vastly underestimating species extinctions.

Tropical communities, for example, which often have many species living in small areas, could be among the hardest hit by climate change. Urban says that this is a first step toward making climate change predictions of biodiversity more sophisticated.

“This a first step – to include in our models things that we know are true, like competition and dispersal,” says Urban. “Knowing these things, can we predict which species might be most at risk?”

Author: Christine Buckley | Source: University of Connecticut [January 03, 2012]

The genomes of 20 Australian and South American marsupials including the Australian tammar wallaby and the South American opossum, were screened by a team lead by Maria Nilsson from the University of Muenster in Germany for repetitive DNA fragments known as retroposons. The presence of shared retroposons in different species can be used to trace relationships and common ancestors. “Our study was the first to apply this method to marsupials, Nilsson said. “And we could resolve parts of the marsupial family tree that have been debated for decades.” Tracing marsupials back to South America

Mainly used by researchers to determine relationships between placental mammals – especially primates – retroposons, or ‘jumping genes’, are pieces of non-functional DNA that are copied from one ancestor to all its descendants. As they are unlikely to arise independently in different species in exactly the same part of the genome by chance, shared retroposons can be used to determine relationships and ancestral lineage.

“Marsupial genomes consist of 52% retroposons, more than any other group, and as such are a great source to find shared retroposons,” Nilsson said of her research, published in PLoS Biology . “The biggest surprise with our results came when we found support for a single origin of Australian marsupials. This can be interpreted as one single group of marsupials migrating from South America across Antarctica to Australia, to give rise to Australian marsupials.”

A furry little contradiction
While this research is based in Germany, Australian researchers are critical of the conclusions. Mike Archer from the University of New South Wales told ABC Science it ignores previously published data which suggest the migration from South America to Australia was “not just a one-way highway, it was a super two-way highway.”

Archer’s evidence lies in the diminutive Dromiciops gliroides, a secretive marsupial commonly known as monito del monte or ‘little mountain monkey’, that lives in the rainforests of Chile and Argentina. Proven in previous studies to be a distant relative of Australia’s earliest known marsupial, Djarthia murgonensis, Archer argues it’s more likely that the Dromiciops originated in Australia and migrated to South America. “The authors are failing to recognise that Australia has been the centre of [marsupial] evolution,” Archer said.

Dromiciops’ mysterious journey
But perhaps the marsupials’ travelling between continents was even more fluid, as suggested by Jenny Graves from the Australian National University in Canberra. “The Dromiciops looks exactly like marsupials you find in Australia, and it’s got the same chromosomes, so we were thinking, ‘What’s it doing in South America?’”

“Maybe it arrived at Australia with the rest of them and then wandered back to South America. But on the other hand, possibly it was left behind.” Katherine Thompson, also from the ANU, originally characterised five of the sequences used in the research, including some of the tammar wallaby markers, Graves said. “It’s great to see some of the sequences we pulled out being put to good use,” she added. cosmosmagazine.com