Thursday, December 31, 2015

Fish Success Story: Cod Makes a Comeback

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Fish Success Story: Cod Makes a Comeback
Fish Success Story: Cod Makes a Comeback
The cod is coming back.

The species that was for centuries a mainstay of the American and Canadian economies had virtually vanished off the Northeastern North American coast by the 1990s owing to overfishing. That led regulators in 1992 to impose a moratorium on cod fishing.
It appears to have worked.
New research shows that cod biomass has increased from the tens of tons to more than 200,000 tons within the last decade. This spring, scientists documented large increases in cod abundance and size for the first time since the moratorium in the more northerly spawning groups, according to a study published Monday in the Canadian Journal of Fisheries and Aquatic Sciences.
“Cod was historically one of the most important fish stocks in the world,” said George Rose, director of the Center for Fisheries Ecosystems Research at the University of Newfoundland in Canada and author of the new report on the cod’s recovery. “When the stocks collapsed in the 1990s, it became the icon of all the bad things we are doing to the ocean, and in many ways, it changed how we deal with our oceans worldwide.”
For hundreds of years, cod were so common—and so huge—that people reported being able to walk across their backs. Cape Cod was named after the fish, and salt cod is credited with sustaining explorers crossing the Atlantic from Spain and Iceland.
When the fishing ban took effect, cod had dwindled to  5 percent of its historic biomass. The moratorium threw 22,000 fishers and processing plant threw employees in more than 400 coastal communities in the United States and Canada out of work.
RELATED: Google Wants You to Fight Overfishing
The moratorium played a big part in the cod’s recovery, as did the return of the fish’s food source, according to the study.
Around the time that cod stocks crashed, a parallel collapse occurred in populations of plankton and capelin, a small smelt fish that provides sustenance for larger fish. “Capelin are the main conduit of energy, from plankton right up to the top of the food chain,” said Rose. “We still don’t know exactly why, but it was really uncertain whether cod could survive the changes at all.”
The first hint of the comeback came in 2008, when researchers saw regrouping of cod on their breeding grounds along with the return of the capelin.
The reasons for the return of the capelin are a mystery, but Rose said it pointed to the need for a more comprehensive approach to fishery management. “This is one of the most important examples why we need to understand the full ecosystem and not just the stocks of fish,” he said.
Cod’s future is still in question. Stocks are low in New England and other parts of the fish’s range where the ocean is warming. But in more northern areas, it is thriving.
He said there are indications that climate change will increase cod populations in Newfoundland and other northern regions.
But don’t expect cod on your dinner plate anytime soon. The Canadian fishing ban remains in place, and the U.S. has also tightened restrictions on cod fishing.
“Nature has kind of given us a second chance,” Rose said. “We don’t want to blow it this time.”

Tuesday, December 29, 2015

Stunning image shows diver through the 'eyes' of a DOLPHIN and reveals animals send images through water to each other

  • Scientists produced the blurred outlines of a submerged man 
  • Recorded sonar signals with underwater microphone and converted them
Extraordinary images conjured from a dolphin's sonar have revealed how the creature 'sees' a human swimmer using echolocation.
Scientists produced the blurred outlines of a submerged man after recording the sonar signals with an underwater microphone and converting them into pictures.
Sophisticated processing was used to transcribe the way sound waves imprint themselves on water and create the images.
Scientists produced the blurred outlines of a submerged man after recording the sonar signals with an underwater microphone and converting them into pictures.
Scientists produced the blurred outlines of a submerged man after recording the sonar signals with an underwater microphone and converting them into pictures.
A similar technique was used three years ago to capture a dolphin's echolocation view of inanimate submerged objects, indicating that cetaceans really can 'see' with sonar.
Team leader Jack Kassewitz, from the US-based SpeakDolphin project promoting communication between humans and dolphins, said: 'This is the first time we have captured a what-the-dolphin-saw image of a submerged man.
'We employed a similar technique in 2012 to capture a dolphin's echolocation picture of a flowerpot and several other submerged plastic objects but the present research has confirmed that result and so much more.'
The research, conducted with the help of British experts, took place at the Dolphin Discovery Centre in Puerto Aventuras, Mexico.
Underwater swimmer Jim McDonough wore a weight belt and exhaled most of the air in his lungs to overcome his natural buoyancy.
A decision was taken not to use breathing apparatus that would generate bubbles which could affect the results of the experiment.
The echo signal was sent via email to a UK scientist who has pioneered new technology called CymaScope that makes sound visible.
The research, conducted with the help of British experts, took place at the Dolphin Discovery Centre in Puerto Aventuras, Mexico.
The research, conducted with the help of British experts, took place at the Dolphin Discovery Centre in Puerto Aventuras, Mexico.
Acoustics physicist Dr John Stuart Reid, from Keswick, who heads the CymaScope team, said: 'When I received the recording Jack had told me only that it might contain an echolocation reflection from someone's face. 
'I noticed the file name 'Jim' so I assumed that the image, if it existed within the file, would be that of a man's face.
'I was somewhat dubious whether this could be achieved because the imaging we had carried out in 2012 was of simple plastic objects that had no inherent detail, whereas a face is a highly detailed form.'
He added: 'I listened to the file and heard an interesting structure of clicks. 
We now think it is safe to speculate that dolphins may employ a 'sono-pictorial' form of language, a language of pictures that they share with each other. 
'The basic principle of the CymaScope instrument is that it transcribes sonic periodicities to water wavelet periodicities - in other words, the sound sample is imprinted onto a water membrane.
'The ability of the CymaScope to capture what-the-dolphin-saw images relates to the quasi-holographic properties of sound and its relationship with water.
'When I injected the click train into the CymaScope, while running the camera in video mode, I saw a fleeting shape on the water's surface that did not resemble a face. 
'I replayed the video, frame by frame and saw something entirely unexpected, the faint outline of a man.'
Computer processing enhanced and cleaned up the image producing more detail, including the weight belt worn by Mr McDonough.
The results suggest that dolphins can sense more than the shadow of an object with their echolocation, and are able to resolve surface features, said Mr Kassewitz.
The results suggest that dolphins can sense more than the shadow of an object with their echolocation, and are able to resolve surface features, said Mr Kassewitz.
The results suggest that dolphins can sense more than the shadow of an object with their echolocation, and are able to resolve surface features, said Mr Kassewitz.
He added: 'The dolphin has had around 50 million years to evolve its echolocation sense whereas marine biologists have studied the physiology of cetaceans for only around five decades and I have worked with John Stuart Reid for barely five years. 
Even so, our recent success has left us all speechless.
'We now think it is safe to speculate that dolphins may employ a 'sono-pictorial' form of language, a language of pictures that they share with each other. 
If that proves to be true an exciting future lies ahead for inter-species communications.'

Scientists discover furry new post-apocalyptic critter that survived demise of the dinosaurs

Sixty-six million years ago, a chunk of space rock the size of a mountain slammed into the Earth. The planet would never be the same.
Debris from the impact went flying into the air, forming clouds so thick they blocked out the sun. Earthquakes shook the ground and sent massive tsunami waves roiling toward shorelines. At the same time — maybe unrelated to the impact, maybe exacerbated by it — a vast flow of lava was flooding across India, oozing ash and noxious gases that caused the climate to fluctuate like a yo-yo and may have helped kill off anything that survived the initial cataclysm.
It was not a good time to be alive, and most species made a swift exit from the global stage: Vegetation withered. Ocean life gasped for air and energy, then collapsed. Gone were the fearsome Tyrannosaurus, the winged Pterosaurs, the massive Triceratops with its three horns and bony neck frill. The dinosaurs’ 100 million-year reign had ended. And when the smoke cleared, a new hero had taken over.
It was buck-toothed and furry and had the goofy appearance of a character from a children’s cartoon. Instead of Earth-shaking stomps, it likely moved with a rodent’s fearful scurry.
Its name is Kimbetopsalis simmonsae, scientists say in a paper published Monday in the Zoological Journal of the Linnean Society. And although it was only about three feet long and no more intimidating than a beaver, it was one of the largest animals around. If Tyrannosaurus was the king of the Cretaceous, Kimbetopsalis was early royalty during the millennia that followed — an era we now call the “Age of the Mammals.”
Kimbetopsalis, which was recently discovered among the shifting sands and spooky rock formations of New Mexico’s badlands, was something of an evolutionary dark horse. First born in the Jurassic period, the fuzzy creature (creatures really — Kimbetopsalis represents a whole new genus) bided its time for a million centuries while dinosaurs tromped about.
After the meteorite-induced apocalypse, “all this ecological space became available and the mammals went a bit nuts,” explained Sarah Shelley, a paleontologist at the University of Edinburgh and a co-author on the paper.
Almost no one went more nuts than Kimbetopsalis, which grew from tiny proportions to the size of a very large beaver over the course of just 500,000 years — a mere blink of an eye in evolutionary terms. Paleontologists believe it had a beaver’s broad face and chunky frame as well, though it lacked a paddle-like tail. 
Though it looks like a rodent, Kimbetopsalis has no living descendants. But it is one of the longest-living groups of mammal in history: its 160-million-year run is longer than that of any mammal species alive today.

Proof of Kimbetopsalis’s existence comes from a few teeth and a fragment of skull discovered during an archaeological dig in a remote New Mexico desert last summer. The fossils were uncovered by Carissa Raymond, a sophomore at the University of Nebraska out on her first dig.
Raymond had never even taken a mammal biology class and had no formal training in fossil finding at the time. But when she called over project leader Thomas Williamson, curator at the New Mexico Museum of Natural History and Science, he “grinned right away,” Shelley recalled.
A new genus had just been discovered.
‭“It’s rare for anybody to find one of these,” Williamson said in a University of Nebraska press release. “I wish I had found it.” ‬ ‭
Teeth are some of the most telling fossils you can find when identifying a new species, Shelley explained — they’re the best indicators of what an animal ate, and what you eat pretty much determines everything about you. From those fragments, Shelley and her colleagues gained a rough understanding of how the ancient mammal looked and lived.
Though it’s now a dry and dramatic desert, at the time New Mexico would have been a lush semitropical forest, full of sustenance for an enterprising young herbivore. Kimbetopsalis had huge, knife-like incisors were ideal for gnawing on plants. And though predators certainly existed, very distant predecessors of modern cattle and horses, life would have been a lot safer than it was before the end-Cretaceous extinction.
Kimbetopsalis was among the biggest, but it was hardly the only mammal to flourish in the newly dinosaur-free world. After epochs of living in the shadows of their larger, lizard-like contemporaries, the early years of what’s now called the Palaeogene period saw the rise of hoofed animals and opossum-like marsupials, bats and even early primates. It pays, it would seem, to be small, good at hiding and willing to wait for a meteorite to wipe out your competitors.
The rapid growth and proliferation of the Kimbetopsalis is a testament to the power of environmental change and the persistence of early mammals, researchers say.
“The history of life hinges on moments that can reset the course of evolution,” , a professor of vertebrate paleontology at the University of Edinburgh and another co-author on the paper, wrote in an essay for the Conversation. Amid the destruction and rapid change caused by the meteorite impact, “dinosaurs couldn’t cope and all of a sudden they were gone. Their size and strength couldn’t save them. Mammals fared better, and now one species of brainy ape occupies that dominant place in nature that was once held by the dinosaurs.”

Thursday, December 24, 2015

Scientists unearth largest dinosaur ever found with wing feathers

With sizable talons and sharp claws the size of human hands, the raptor was deadly. It could also chase down just about anything.
By Brooks Hays   |   Nov. 5, 2015 at 12:28 PM
An artistic rendering of the largest raptor with winged feathers. Photo by Emily Willoughby/University of Kansas
LAWRENCE, Kan., Nov. 5 (UPI) -- A team of paleontologists have discovered a new raptor, the largest dinosaur specimen ever found with wing feathers.
Named Dakotaraptor steini, the dino was found in the famed fossil-rich Hell Creek Formation of South Dakota's badlands. The bones are 66 million years old. Scientists say the ancient velociraptor relative was capable of reaching 17 feet in length and boasted a wingspan of nearly four feet.
Only the 23-foot Utahraptor grew larger, and it died out 60 million years before Dakotaraptor arrived on the scene.
The Cretaceous-era creature, recently described in the journal Paleontological Contributions, lived alongside popularized species like Tyrannosaurus and Triceratops.
"This new predatory dinosaur also fills the body size gap between smaller theropods and large tyrannosaurs that lived at this time," David Burnham, a paleontologist at Kansas and co-author of the new study, said in a press release.
Unlike other winged dino species, which evolved into flight, researchers think Dakotaraptor took the opposite path -- having grown too large for flight, its feathers a remnant of its evolutionary past.
But that doesn't mean its feathers were useless, researchers say. Dakotaraptor likely used its wing feathers as a way to attract mates, shield young offspring from predators or to pin down prey when hunting.
Feathers or no feathers, Dakotaraptor was a fearsome predator. With sizable talons and sharp claws the size of human hands, the raptor was deadly. It could also chase down just about anything.
"Dakotaraptor was probably the fastest predator in the entire Hell Creek Formation," lead study author Robert DePalma, curator of vertebrate paleontology at the Palm Beach Museum, told the Smithsonian Magazine. "It was the Ferrari of raptors."
The raptors may have hunted in packs. And if so, a group of them could have taken down tyrannosaurs.
Like the rest of Earth's non-avian dinosaurs and 75 percent of all living creatures, Dakotaraptor was wiped out some 66 million years ago by the Cretaceous-Paleogene extinction event.

Fossil With Preserved Tail Feathers and Skin Reveals Dinosaur Plumage Patterns




George Dvorsky11/02/15 11:15am



An undergraduate student from the University of Alberta has uncovered the fossilized remains of an Ornithomimus dinosaur with preserved tail feathers and soft tissue. The remarkable specimen is offering important insights into the plumage patterns of these ancient creatures, while tightening the linkages between dinosaurs and birds.

The 75-million-year-old fossil, discovered by paleontologist Aaron J. van der Reest in the Upper Cretaceous Dinosaur Park Formation of Alberta, is the first to show traces of preserved skin from the femur to the abdomen in a non-avian dinosaur. It’s considered the most complete feathered dinosaur specimen found in North America to date, the details of which can now be found at the science journal Cretaceous Research.

Analysis of the fossil shows that Ornithomimidae—a genus of omnivorous bipedal dinosaurs—were not covered in feathers from head-to-toe. Like modern-day ostriches, their legs were bare.

1
(Credit: A. J. Reest et al., 2015)

“We now know what the plumage looked like on the tail, and that from the mid-femur down, it had bare skin,” noted van der Reest in a release. “Ostriches use bare skin to thermoregulate. Because the plumage on this specimen is virtually identical to that of an ostrich, we can infer that Ornithomimus was likely doing the same thing, using feathered regions on their body to maintain body temperature. It would’ve looked a lot like an ostrich.”

A flightless dinosaur, it stood 6.5 feet (2 meters) tall, and featured a small head with a toothless beak. The fossil is only the third ornithomimus specimen to exhibit traces of feathers, and it’s shedding light on how certain animals adapt to different environments.

“We are getting the newest information on what these animals may have looked like, how they maintained body temperatures, and the stages of feather evolution,” says van der Reest.

As science report Ivan Semeniuk points out in the Globe and Mail,

Birds are thought to have evolved from a different line of dinosaurs than ornithomimus. Rather than indicating direct ancestry, the new fossil suggests that many features recognized in bird feathers today were present long before, in a common ancestor to both ornithomimids and birds. Together with fossils found in China that date back to a similar period, the new discovery promises to clarify how and when such features emerged.

Indeed, this specimen also tightens the linkages between dinosaurs and birds, particularly with respect to theropods—carnivorous bipedal dinosaurs.
“There are so many components of the morphology of this fossil as well as the chemistry of the feathers that are essentially indistinguishable from modern birds,” added study co-author Alexander Wolf.
Read the entire study at Cretaceous Research: “A densely feathered ornithomimid (Dinosauria: Theropoda) from the Upper Cretaceous Dinosaur Park Formation, Alberta, Canada”.

Wednesday, December 23, 2015

Scientists suggest a new, earth-shaking twist on the demise of the dinosaurs

October 19
New research suggests that the asteroid or comet that slammed into the Earth 66 million years ago rocked the planet so violently that it accelerated a massive volcanic eruption in India, a double catastrophe that wiped out the dinosaurs and 70 percent of the Earth's species.
The study, published Thursday in the journal Science, puts a twist on the consensus explanation of the mass extinction at the end of the Cretaceous period. Scientists have long been confident that a mountain-sized object crashed into the planet, leaving traces even today of a vast crater at the tip of Mexico's Yucatan peninsula.
[Don’t worry. Matt Damon won’t get stuck on Mars. NASA can’t get him there.]
They’ve also known that massive volcanism in India was happening around the same time, spreading lava across a huge region known as the Deccan Traps. The coincidence of those two events initially hinted at causality, but subsequent dating of the Deccan Traps formations indicated that the flood of basaltic lava began long before the cataclysmic impact.


With the new data, causality's once again in play. The asteroid or comet didn’t cause the initial eruption, but it could have intensified it, according to the paper.
The Chicxulub impact – named after a town in the Yucatan – created earthquakes of magnitude 11 in the vicinity of the crater, the authors say. Magnitude 9 earthquakes would have been felt around the planet, they say.
[A ‘lost world’ of dinosaurs thrived in the snowy dark of Alaska]
The seismic energy made the planet's crust more permeable. Molten rock deep in the interior began flowing through fractures. As that magma expanded, gasses in the solution began forming bubbles. As with a shaken soda bottle, the results were likely explosive.
“Once that’s initiated, it becomes a kind of runaway process,” said Paul Renne, a University of California, Berkeley geologist and lead author of the new paper.

First ever evidence of a swimming, shark-eating dinosaur

 https://www.washingtonpost.com/

When it wasn't putting T. rex to shame, the dinosaur Spinosaurus spent its time swimming -- and chowing down on sharks.
Until now, scientists didn't have any proof that there were swimming dinosaurs. There were some marine reptiles prowling the seas, to be sure, but paleontologists couldn't find fossils that put dinosaurs in the water.
New fossil evidence published Thursday in Science changes that, and the  Spinosaurus aegyptiacus is breaking records left and right. It's now the largest predatory dinosaur to have ever roamed the planet — nearly 10 feet longer than the largest T. rex specimen — although the carnivore was still dwarfed by some of its plant-eating contemporaries. But more importantly, Spinosaurus has the distinction of providing our first ever evidence for a semi-aquatic dinosaur.


Spinosaurus was discovered in the Sahara more than a century ago by German paleontologist Ernst Freiherr Stromer von Reichenbach, but all of his fossils were destroyed during World War II.
When a partial skeleton was uncovered in the Moroccan Sahara -- in a place once home to a massive system of rivers full of all sorts of sharks and other predators  -- scientists had a new clue that there was something fishy about the massive dino.
In addition to revealing a record-breaking length, digital modeling of the skeleton suggested a whole fleet of aquatic adaptations. Tiny nostrils, placed far back on the middle of the dinosaur's skull, presumably allowed it to breathe as it swam at the surface. It also had openings at the end of its snout that are reminiscent of ones in crocodiles and alligators. In the modern animals, these openings house receptors that let them sense movement in the water.

Huge, slanted, interlocking teeth seem perfectly shaped to catch fish, and hook-like claws would have been ideal for catching hold of slippery prey under the water. Big, flat feet (perhaps even webbed) would have been well-suited to paddling water or stomping through mud, and some unusually dense limb bones (more like those seen in penguins than those found in other dinosaurs, the researchers report) would have allowed it to keep itself under the water, instead of floating.
The dinosaur's skeletal shape indicates that it would have been a strange sight to us on land. The Spinosaurus's center of gravity was pushed forward by its long neck, so it was almost certainly impossible for it to walk on two legs. In fact, the Spinosaurus's legs and pelvis are quite like those seen in early whales -- much better for paddling than for walking. Like whales, these dinosaurs probably evolved from land-dwelling ancestors to become semi-aquatic.

Scientists aren't quite sure how Spinosaurus moved when it left the water -- which it must have done, at the very least, to lay and nest eggs. Spinosaurus didn't have the kind of limbs that scientists would expect in a four-legged animal, but it also couldn't have balanced on its hind legs for very long.
"I think that we have to face the fact that the Jurassic Park folks have to go back to the drawing board on Spinosaurus," co-author and University of Chicago paleontologist Paul Sereno said in a teleconference held by Science on Wednesday. "It was not a balancing, two-legged animal on land. It would have been something very peculiar."
This isn't to say that Spinosaurus wouldn't have been an impressive sight on land. "It would have been a fearsome animal. There's no question about it, you would not want to meet this animal on land," Sereno said. "But it was not gallivanting across the landscape."
While paleontologists continue to puzzle over how the Spinosaurus managed to walk, you can visit a life-size skeletal replica of the creature at the National Geographic Museum in Washington. The exhibit will run Sept. 12th through April 12.



Were dinosaurs warm or cold blooded? Ancient eggshells could reveal the truth.

https://img.washingtonpost.com

Were dinosaurs warm or cold blooded? New data suggests that the answer might be a simple "yes".
Back in the day, paleontologists assumed that dinosaurs were all lizard-like, and had the slow metabolisms to match — making them cold blooded, like alligators. These kinds of animals, more formally known as ectotherms, have to get most of their body heat from their environment. Endotherms, like humans and other mammals, are capable of producing most of the heat they need internally.
[Fossils might reveal the colors of ancient critters]
Now we know that many dinosaurs were actually bird ancestors. Birds are endothermic, and have super fast metabolisms.
So did some dinosaurs have bird-like metabolisms, and the hot blood to match? A study published Tuesday in Nature Communications claims to have found the answer in fossilized eggshells.
The basic findings line up with what most recent research in the area has concluded: Dinosaur metabolisms were all over the place.
"It's important to realize that there's actually a whole sliding scale of physiology," even in the modern animal kingdom, study author Robert Eagle of the University of California told The Post. Birds have metabolic rates that put humans to shame, he explained, making them arguably more "warm blooded" than we are. And then you have critters like sloths, that are on the slowest, coolest end of the warm blooded spectrum. "So the real question is where dinosaurs fell on that spectrum," he said.
[A crummy dinosaur fossil turns out to hold 75 million-year-old blood and proteins]
That's where Eagle's work comes in. He and his colleagues analyzed the chemical makeup of ancient eggshells, using a technique previously perfected on teeth to estimate the temperature of the body they formed in. By measuring the abundance of chemical bonds between two rare, heavy isotopes (carbon-13 and oxygen-18) in calcium carbonate minerals, scientists can estimate body temperature. A mineral that forms at colder temperatures will have more of these bonds than the same mineral formed at a higher temperature. In the case of an egg, scientists can use this ratio to estimate the temperature of the mother's body when she formed it. 
After showing that this measurement worked in eggs from modern animals, Eagle and his colleagues tested fossilized eggs. Many showed signs of decay that would alter any conclusions about temperature, but they were able to analyze two species successfully — and found signs of a range of metabolic rates.
One was a long-necked titanosaur sauropod, and it indicated a maternal body temperature of about 100 degrees Fahrenheit, comparable to large mammals today. Another species — a T. rex-like oviraptorid — indicated a cooler 90-degree body temperature, which is lower than most modern mammals.
But chances are that both of them were at least somewhat endothermic, Eagle explained. Analysis of the soil around the oviraptorid eggs indicates that the air temperature may have been lower than their body temperature.
"We can't take just body temperature and jump to the conclusion that they weren't cold blooded," Eagle said, "but combined with other data, it's consistent with them having some kind of intermediary metabolism. This suggests that maybe they were warm blooded, but hadn't developed the high level of temperature regulation seen in mammals and birds today. They were kind of part way to evolving endothermy."
Since oviraptorids like this one were close relatives to the earliest birds, Eagle hopes that studying the evolutionary lineage more closely will reveal when and how metabolisms sped up so drastically.
"There's just a massive spectrum of different questions we can ask now," he said.

Tuesday, December 22, 2015

What color were dinosaurs really? Bat fossils reveal clues.


In a paper published Monday, researchers used well-preserved fossils to determine the color of 50-million-year old animals. 

 
(Bob Walters/Reuters)
 
For the first time ever, researchers studying fossils have discovered extinct mammal’s true colors.
The scientists studied two species of bats, Palaeochiropteryx and Hassianycteris, who lived along a lake in a tropical forest in Germany in the Eocene Epoch, 56 million to 33.9 million years ago.
In their study published Monday in the Proceedings of the National Academy of Sciences, scientists from the University of Bristol and Virginia Tech examined bat fossils that were so excellently preserved that they retained melanosome structures.
Skeptics had previously assumed that melanosomes in other well-preserved fossils were just bacteria. But molecular paleobiologist Jakob Vinther of Britian’s University of Bristol and his team have confirmed for the first time that the structures contained melansome remnants, not bacteria, by studying the microchemistry of the fossils.

Why are melansomes so exciting?
Melansomes contain melanin, the pigment that gives certain colors to skin, fur or hair, and scientists can use the size and shape of melanins to determine their original color.
“This means that the correlation of melanin colour to shape is an ancient invention, which we can use to easily determine colour from fossils by simply i at the melanosomes shape,” Dr. Vinther explains in a University of Bristol press release.
“People had questioned whether you could use the shape of the melanosome to tell anything about the color, because it’s been through a lot. Millions of years in the ground is obviously going to take a toll,” Cailtin Colleary, a Ph.D. student in geological studies at Virginia Tech University and the study’s lead author told The Atlantic.
“So by finding traces of the chemical melanin in association with these structures, we’ve basically confirmed that you can use the shapes of the melanosomes themselves to tell what color something was,” she said.
So what color were these bats? Drum roll please….
Well, the bats are brown,” Vinther told Reuters. “It might not be a big surprise, but that’s what these 49-million-year-old bats are. So they looked perfectly like modern bats.”
And while paleontologists are not surprised by their finding, they say it’s nice to finally know for sure.
“Since so little is preserved in the fossil record, the color of extinct animals has always been left up to artists’ interpretations, and important information regarding behavior has been considered inaccessible,” Ms. Colleary told Reuters.
What can an animal's color tell you about the species' behavior? Important stuff, like what type of environment the animals lived in, how they attracted mates, or how they protected themselves against predators, says Ms. Colleary.
“For complex animal life, color is a factor in how individuals recognize and respond to others, determine friend or foe, and find mates,” said MIT geobiologist Roger Summons, in a Virginia Tech press release. “This research provides another thread to understand how ancient life evolved. Color recognition was an important part of that process, and it goes far back in the history of animals.”
“I think we’re just scratching the surface in our ability to extract information like this from the fossil record,” adds Colleary. “As technology continues to advance, we’ll keep finding information in fossils that we don’t even know is there today.”

Scientists Have Drafted a Complete Tree of Life



Maddie Stone9/19/15 3:00pm



Humans, bacteria, daffodils: We’re a diverse bunch on the surface, but trace each and every Earthling back far enough, and you’ll arrive at a common ancestor. For the first time, scientists have built a comprehensive tree of life that binds us all together.

A draft of the One Tree, published Friday in the Proceedings of the National Academies of Sciences, includes the roughly 2.3 million named species of animals, plants, fungi and microbes. It shows how all of the major branches relate to one another and traces each individual group back to its shared beginnings in a prebiotic soup 3.5 billion years ago.

“This is the first real attempt to connect the dots and put it all together,” said principal investigator Karen Cranston of Duke University in a statement. “Think of it as Version 1.0.”




This family tree of Earth’s lifeforms is considered a first draft of the 3.5-billion-year history of how life evolved and diverged. Image Credit: opentreeoflife.org

To build the tree of all life, researchers compiled thousands of smaller trees that had already been published online. One of the big challenges was simply accounting for the different taxonomic names, spellings and misspellings that crop up across scientific papers. For instance, in a strange fluke of taxonomy that I can only hope has inspired some fantastically weird artwork, spiny anteaters once shared their scientific name with moray eels.

The tree will continue to receive updates over time, of course — scientists are still discovering new species of plants, animals and fungi every year, and with our growing arsenal of genomic sequencing tools, we’re finally beginning to unlock the vast diversity of the microbial world. The team behind the tree is developing software tools that’ll enable researchers to log in and revise things as new data is collected.

In the meanwhile, the biology nerds in the room can start exploring all of this juicy data right now. The tree, along with the raw data and source code that built it, is available for free online at https://tree.opentreeoflife.org.

[Read the full scientific paper at PNAS h/t phys.org]

Saturday, November 21, 2015

Fossilized Tropical Forest Found — in Arctic Norway

LiveScience.com

Fossilized Tropical Forest Found — in Arctic Norway
Partial tree trunk with the base preserved, at the site in Svalbard (left) and a reconstruction of what the ancient forest look liked 380 million years ago (right)
A tropical forest densely packed with 12-foot-tall trees with flared trunks and curved branches of needle leaves — Dr. Seuss would have felt right at home — covered an area near the equator some 380 million years ago. Scientists spotted the fossilized stumps a long way from this location — in Arctic Norway.
Not only did the researchers date the forest as one of Earth's oldest, but they also suggest it may have contributed to a dramatic drop in atmospheric carbon dioxide levels traced to that time in our planet's distant past.
During the Devonian period (416 million to 358 million years ago), Earth's first large trees were emerging. Also around this time, atmospheric carbon dioxide dropped significantly. Scientists look to the earliest forests for evidence that tree growth played a part in scrubbing CO2 from the atmosphere — trees use the greenhouse gas to photosynthesize and form sugary food — contributing to the global cooling event that occurred at the end of the Devonian.
The recent discovery of an ancient forest in Svalbard, a cluster of Norwegian islands in the Arctic Ocean, caught the attention of Chris Berry of Cardiff University, co-author of the study. When Berry heard about the forest from a German colleague who had worked there, he told Live Science in an email, he was eager to investigate the site, where many of the forest's tree stumps are still evident. [See Photos of the Fossil Forest Remains Found in Norway]
"I have been working a lot on fossil trees from the Devonian by looking at the fragmentary fossils, and trying to assemble them back into whole plants," Berry said. "That's fun, but finding the stumps in the ground tells you a lot more about their ecology," he added.
Older than expected
Berry's colleague, John Marshall of Southampton University, calculated the forest's age by extracting spores from rocks, and comparing them with other spores from similar sites. They found that the fossil forest was actually 20 million years older than previously estimated. Marshall and Berry realized that they were dealing with something "right from the beginnings of forest ecosystems," Berry said.
They suspected that the trees originally grew in a basin, covering an area about 0.6 miles (1 kilometer) in width and 3.1 miles (5 kilometers) in length, though only a few square meters of fossil remains are currently visible at the surface. The scientists investigated three small areas in Svalbard where fossil material was visible on the ground. And there was even more to be seen in cliffs found nearby.  "In the cliffs there are many layers of fossil trees, one on top of the other. You just can't get a view from on top to map them out," Berry told Live Science.
Getting the drop on CO2
Before continental drift carried the forest north by several thousand miles, the forest was growing close to the equator. But Svalbard's forest didn't resemble modern tropical forests. The ancient trees that appeared 380 million years ago were mostly lycopsids, also known as "club mosses."  Lycopsids produce leaves with a single vein and reproduce with spores; there are about 1,200 species of lycopsid still alive today.
In Svalbard, lycopsids grew to a height of about 13 feet (4 meters) and would have been tightly packed, with gaps of about 0.7 feet (20 centimeters) between trees. Their trunks would have flared slightly at the bottom, with some holding diamond- or oval-shaped patterns. Trees "scrub" carbon dioxide from the atmosphere by absorbing it through photosynthesis, and forests such as these would likely have absorbed a lot more CO2 than the smaller plant life that previously covered the planet.
In a statement, Berry described the appearance of trees on Earth as "the most likely cause" of the drop in atmospheric carbon dioxide during the Devonian, when CO2 plummeted from about 15 times what it is now, to an amount more like the atmospheric CO2 levels today.
Early diversity
The Svalbard forest isn't the only ancient, preserved forest still around — Berry previously analyzed another, older forest in Gilboa, New York. But the composition of that forest was different. Giant palmlike trees in beds made of thousands of roots dominated the landscape, and there were very few lycopsids.
Interestingly, the trees that were most plentiful in Gilboa were completely absent in the Svalbard forest. "It suggests that more than one tree group was forming forests and these forests were not the same everywhere on the planet," Berry told Live Science.
The finding is detailed Nov. 19 in the journal Geology.

Thursday, November 19, 2015

10 Incredible Firsts In The Evolution Of Life On Earth

 http://listverse.com/

Kyle Roberts
In order to attain the awe-inspiring diversity of life on this planet, nature had to overcome numerous obstacles over billions of years of evolution. New environments had to be conquered; new forms had be created to exploit newly available resources. Since man first began to look back through the long history of the natural world via paleontology and geology, we’ve uncovered some of the turning points in the development of life on Earth.

10The Earliest Humans
The Omo Remains

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Of course, you can trace humanity’s family tree back a long way. But who were the earliest modern humans, like you and the people you know? Well, Omo I and II might just hold the answers. The two partial skulls, discovered in Ethiopia around 1967, were recently confirmed to be an astonishing 195,000 years old, making them the earliest known anatomically modern humans. (There actually is some debate around Omo II, but Omo I is agreed to be a fully modern human.) In fact, scientists now think that Homo sapiens only evolved around 200,000 years ago, making it likely that the Omo pair were among the first true humans ever to walk the Earth.
So what are the implications of the two skulls? Well, aside from confirming humanity’s emergence in Africa, they’ve deepened one of the great mysteries of human evolution. Evidence of cultural traits—like musical instruments, needles, and ornaments—only dates back to around 50,000 years ago. Complex tools like harpoons also appear after that date, although crude stone implements date back much further. So, if entirely modern humans were roaming the land 200,000 years ago, why did it take them 150,000 years to develop anything resembling culture?

9The Earliest Bird
Protoavis

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Photo via Wikimedia
 
We now know that birds evolved from dinosaurs, and that many dinosaurs were actually covered in feathers. As a result, the question “Which was the earliest bird” can seem more like “When do we stop considering a creature a dinosaur and start calling it a bird?” For a long time, paleontologists drew the line at creatures like Archaeopteryx (pictured) and Confuciusornis, small animals covered in feathers and capable of flying, as well as climbing trees and running. We also know that Confuciusornis had a genuine beak, which gives it an advantage over its rivals for the position of earliest true bird.
However, there is an even older candidate for the title of first bird. Protoavis lived around 220 million years ago, at least 80 million years before its nearest rival. The fossil was found in Texas by paleontologist Sankar Chatterjee, who argues that it is even closer to modern birds than Archaeopteryx. If this is true, and Protoavis is the oldest known bird, it would potentially rewrite our entire understanding of avian evolution. Currently, the consensus is that birds evolved from coelurosaurian dinosaurs. But Protoavis is easily as old as the first coelurosaurians, making such a scenario impossible. If Protoavis is a bird, then birds must have come from somewhere else.
Don’t rewrite the textbooks just yet, though, because the identification of Protoavis as a bird has proven enormously controversial. The fossil was not in good condition when Chatterjee found it, leading many paleontologists to suggest it’s actually a mixture of bone fragments from two or more species, which an overeager Chatterjee pieced together into a plausible skeleton. Others simply point out that there’s no reason to believe Protoavis is the ancestor of today’s birds. Instead, convergent evolution might simply have resulted in two unrelated species sharing a similar design.

8The First Species To Walk On Land
Tiktaalik And Pneumodesmus


Part fish, part frog, and part alligator, Tiktaalik was the platypus of the Devonian, splashing in the shallows some 375 million years ago. Discovered in Canada in 2004, the species is considered to be an important transitional link between aquatic vertebrates and the very first land animals. Among other adaptations, Tiktaalik boasted ribs capable of supporting its body, lungs, a movable neck, and eyes on the top of its head like a crocodile. It also boasted proto-legs, halfway evolved from fins, that would have allowed it to push itself along riverbeds. However, Tiktaalik‘s “legs” probably didn’t have the range of motion required to truly walk on land. At best, it might have been able to briefly scramble around on mud flats. Otherwise, it probably remained in the shallows.
But while vertebrates like Tiktaalik struggled to make the transfer to land, they had actually been beaten to the punch by a species of millipede known as Pneumodesmus, which lived some 428 million years ago. At just 1 centimeter (0.4 in) in length, the tiny myriapod wasn’t much to look at, but Pneumodesmus was the first creature we know of to actually live on land. That also makes it the oldest air-breathing creature we know of, boasting tiny breathing openings known as spiracles on the outside of its body. As such, Pneumodesmus must be considered one of nature’s most successful experiments, paving the way for all the land animals to come.

7The Earliest True Reptile
Hylonomus Lyelli

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Reptiles were the first vertebrates to become completely capable of living on land, even reproducing outside of the water. That makes them pretty awesome, and the tiny critter known as Hylonomus lyelli might just be the most awesome of them all. The lizard-like creature, which measured just 20 centimeters (8 in) in length, is currently the oldest undisputed species of reptile, dating back at least 310 million years. Probably an insectivore, Hylonomus lyelli was discovered in 1860, preserved inside a tree trunk in Nova Scotia.
Of course, 1860 was a long time ago and two challengers to the first reptile title have emerged since then. Westlothiana and Casineria are both slightly older than Hylonomus lyelli (338 million years for Westlothiana and 335 million years for Casineria). However, the scientific community is still debating whether either was indeed a fully evolved reptile, since they share some amphibian traits, meaning that they were probably dependent on a stable water source to live and reproduce. For the time being, Hylonomus lyelli can keep its title.

6The Oldest Creature Capable Of Flight
Rhyniognatha Hirsti

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As a means of locomotion, flight requires a complex design (low body weight, but a sturdy frame) and a lot of effort by powerful wing muscles. The first creature capable of flight was actually the oldest known insect, Rhyniognatha hirsti. The tiny insect lived some 400 million years ago, meaning that flight is by no means a recent development from an evolutionary perspective.
Rhyniognatha hirsti was discovered in 1928, in rocks dating back to the Devonian. The fossil was promptly ignored for almost 75 years, until biologist Michael Engel accidentally rediscovered it in a drawer in London’s Natural History Museum. Engel gasped out loud on spotting the incredible specimen—and that was before he even knew how old it was.
Since then, experts have studied its remains thoroughly, confirming that the tiny insect had wings and was very likely capable of using them to fly. However, they are still not completely certain which family of insects it belonged to. Nevertheless, the fossil is a fascinating find and further study should reveal more about the earliest known pioneer of flight.

5The First Flowering Plants
Potomacapnos And Amborella

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Photo via Wikimdia
People tend to associate plants with flowers, but flowers are actually a very recent development, at least on the evolutionary timescale. Before they showed up, plants reproduced via spores for hundreds of millions of years. In fact, scientists aren’t even sure why flowers evolved in the first place, since they are delicate and require huge amounts of energy, which many plants might put to better use growing seeds or increasing in height. Additionally, non-flowering plants have nothing that really corresponds to flowers, making it something of a puzzle where they came from in the first place. These loose ends led Darwin to famously describe the rise of flowers as “an abominable mystery.”
The oldest known flowering plant fossils date to the Cretaceous, between 115 and 125 million years ago. Among the oldest is Potomacapnos, a surprisingly complex plant resembling a modern poppy. Such complexity in early fossils indicates that flowers probably evolved very rapidly to something approaching their modern form, rather than slowly developing over a lengthy period. But it’s hard to draw any firm conclusions, since flowers are fragile and rarely survive to be fossilized.
However, some answers might lie with a rare shrub found only on the Pacific island of New Caledonia. Amborella trichopoda (pictured) is the only surviving member of the Amborellales. At the start of the Cretaceous, the Amborellales split from the non-flowering plants dominating the landscape, becoming the oldest order of flowering plants to survive into the present. Later, two other surviving orders emerged: the Nymphaeales, which became modern water lilies, and the Austrobaileyales, from which all other flowering plants developed. Since the Amborellales emerged first, Amborella trichopoda remains closest to the original flowering plants. By comparing it with the Austrobaileyales, we can get some idea of which traits flowering plants originally boasted and which simply evolved further down the line.

4The Earliest Mammal
Hadrocodium Wui

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The oldest known mammal resembled a small mouse or modern-day shrew. Hadrocodium wui, identified in China in 2001, was some 3.5 centimeters (1.4 in) long, weighed 2 grams, and probably had a lifestyle and diet similar to modern shrews, since its teeth consisted of specialized fangs for chopping up insects.
So how do we know that Hadrocodium was a mammal and not a therapsid (a type of mammal-like reptile that flourished in the Mesozoic)? Well, as well as a notably large brain for its size, Hadrocodium boasted middle-ear bones separate from its jaw, which is considered a notable point of evolutionary divergence between mammals and reptiles. In fact, Hadrocodium could be considered quite modern in its design, especially when it comes to its sense of smell.
However, what makes Hadrocodium wui truly impressive is its age. At 195 million years old, Hadrocodium lived long before some of the best-known dinosaurs, including the stegosaurus, diplodocus, and tyrannosaurus. In fact, the mighty tyrannosaurus lived closer to us in time than it did to Hadrocodium wui.

3The First Tree
Wattieza

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Photo via Wikimedia
 
Trees played (and still play) a crucial role in the formation of the Earth’s atmosphere. Without their power to convert carbon dioxide into oxygen, the planet would quickly become inhospitable to life, at least as we know it. In fact, the first forests drastically changed our ecosystem, causing the planet to cool and directly creating the conditions we take for granted today. As such, the appearance of the tree can be considered one of the most important evolutionary breakthroughs of all time.
Currently, the oldest known tree is a 397-million-year-old species known as Wattieza, which resembled a modern palm and probably reached a height of around 10 meters (30 ft). Wattieza preceded the dinosaurs by some 140 million years, spreading across the planet long before the first vertebrates took to the land. It reproduced using spores, similar to those used by ferns and fungi today. The species is currently extinct, but a 180-kilogram (400 lb) fossil (pictured above) was discovered in New York in 2004, solving many unanswered questions about how forests came to dominate the land.

2The Earliest True Dinosaur
Nyasasaurus Parringtoni


The reign of the dinosaurs began after the dreadful Permian extinction, which took place some 250 million years ago and wiped out around 90 percent of all species on Earth, including 95 percent of marine life and most of the planet’s trees. Afterward, the dinosaurs emerged.
The oldest true dinosaur currently known is Nyasasaurus parringtoni, which was discovered in Tanzania in the 1930s, but only conclusively dated in 2011. Only a few bones from the species have been identified so far—scientists still have no clue whether it was a carnivore or a herbivore, nor are they completely certain whether it walked on two legs or not.
Nevertheless, we can say that Nyasasaurus parringtoni was less-than-imposing, standing just 1 meter (3 ft) tall and weighing 18–60 kilograms (40–135 lb). In fact, it’s barely even a dinosaur by most standards, but analysis of its bones has revealed that it was a fast-growing animal, indicating that it was warm-blooded, an essential trait of dinosaurs. For now, the scientific community hopes to discover more fossils, since we haven’t even been able to identify the family of dinosaurs it belongs to yet.

1The Oldest Life-Form

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What is the oldest life-form known to science? Well, it’s a surprisingly tricky question to answer, since early life-forms were so basic its often hard to identify them accurately. For example, rocks discovered near Pilbara in Australia were initially thought to contain traces of a purple, ocean-dwelling microbial community almost 3.5 billion years old. This would have been the oldest evidence of life on Earth and everyone got very excited—until earlier this year, when new testing conclusively proved that the “microfossils” were actually just strangely shaped mineral deposits created by hydrothermal events. In other words, they were never alive at all.
The same thing happened in South Africa, where tiny tubes found in rocks were taken as evidence of 3.4-billion-year-old bacteria, only for a subsequent study to identify them as natural formations created by volcanic activity. Fortunately, these revelations haven’t set the hunt for the oldest fossil back too far, since Australia’s Strelley Pool Formation contains carbon-rich “bag-shaped bodies” that are considered to be convincing evidence of ancient microbial life. At 3.43 billion years old, the Strelley Pool deposits are only about 20 million years younger than the Pilbara “microfossils” were thought to be.
Intriguingly, there’s some evidence that the Strelley Pool organisms were photosynthetic, surviving by converting light to energy. Although no fossil record of them has been found, it’s generally agreed that the earliest bacteria were rock-eaters known as chemolithotrophs, with photosynthetic bacteria emerging later. So we can be pretty sure that the earliest bacteria predate even the Strelley Pool deposits by a long, long time.

Friday, October 23, 2015

Plague spread 3,000 years earlier than 1st thought: 2,800 BC

Associated Press
In this undated photo released by Cell journal, the Sope I grave in Estonia, where plague DNA was found in a tooth from this individual and is the earliest evidence of plague found in Europe.  The plague was spreading nearly 3,000-years before previously thought, according to findings published Thursday Oct. 22, 2015, in the journal Cell.  Scientists have found traces of the disease in the teeth of ancient people, although the Bronze Age plague revealed by the new study seems to have lacked the ability to spread over wide regions, so probably remained in local pockets of disease.  (Harri Moora / Cell 2015 via AP)
LONDON (AP) — The plague was spreading nearly 3,000 years before previously thought, scientists say after finding traces of the disease in the teeth of ancient people — a discovery that could provide clues to how dangerous diseases evolve.
To find evidence of the prehistoric infection, researchers drilled into the teeth of 101 individuals who lived in Central Asia and Europe some 2,800 to 5,000 years ago. The drilling produced a powder that the researchers examined for DNA from plague bacteria. They found it in samples from seven people.
Before the study, the earliest evidence of the plague was from A.D. 540, said Simon Rasmussen of the Technical University of Denmark. He and colleagues found it as early as 2,800 B.C.
"We were very surprised to find it 3,000 years before it was supposed to exist," said Rasmussen, one of the study authors. The research was published online Thursday in the journal, Cell.
Rasmussen said the plague they found was a different strain from the one that caused the three known pandemics, including the Black Death that swept across Medieval Europe. In contrast to later strains, including the one estimated to have wiped out about half of Europe, the Bronze Age plague revealed by the new study could not be spread by fleas because it lacked a crucial gene. So it was probably less able to infect people over wide regions.
But Rasmussen said knowing that plague existed thousands of years earlier than had been believed might explain some unsolved historical mysteries, including the "Plague of Athens," a horrifying unknown epidemic that struck the Greek capital in 430 B.C. It killed up to 100,000 people during the Peloponnesian War.
"People have been speculating about what this was, like was this measles or typhus, but it could well have been plague," Rasmussen said.
He said tracking how the plague evolved from being an intestinal infection to "one of the most deadly diseases ever encountered by humans" could help scientists predict the disease's future path.
"Typically, things get less virulent with time, but that's not always the case," said Hendrik Poinar, a molecular evolutionary geneticist at McMaster University in Canada who was not part of the study. He noted that diseases could acquire new features — including lethality — relatively quickly.
Other experts said it was unlikely that plague would ever pose as great a threat as it has in the past, especially since it is now largely treatable.
"It might be that (plague) will eventually burn itself out," said Brendan Wren, dean of the faculty of infectious and tropical diseases at the London School of Hygiene and Tropical Medicine. Wren said other diseases like leprosy have also lost genes over time and are now less able to sicken people.
"The evidence is that (plague) is not going to come back big time, but it's hard to predict what the bacteria will do," he said. "They are great survivors."