Friday, April 4, 2014

Evolution news for April Fools

I haven't posted any evolution news here since Discovery News on radiometric dating.  That understates the amount of evolution stories I have in my archive, as I haven't posted any of those since Evolution news for Darwin Day.  That means it's time for another compilation.

Under the "if it moves, it leads" policy, Discovery News goes first with Humans Are Still Evolving!

Human evolution happened slowly over the course of thousands and thousands of years. Are we still evolving today? Trace discusses a few recent findings showing how humans, even in the past 5,000 years, are continuing to evolve!
Speaking of humans still evolving, Jennifer Viegas of Discovery News has more on the topic in How Humans Went From Being One Shade to Many.
Our primate ancestors that first lost most of their body hair were likely pale skinned, according to a new study that concludes our human forebears probably evolved darker skin later to safeguard against skin cancer and other problems that can result from too much sun exposure.

The study, published in the latest Proceedings of the Royal Society B, helps explain both the historical origins and biological significance of skin coloration in humans.
Follow over the jump for the rest of the paleontology and evolution stories from the past two months of Overnight News Digest on Daily Kos.

General Evolution

Virginia Tech: Virginia Tech scientist proposes revolutionary naming system for all life on Earth
BLACKSBURG, Va., Feb. 24, 2014 – A Virginia Tech researcher has developed a new way to classify and name organisms based on their genome sequence and in doing so created a universal language that scientists can use to communicate with unprecedented specificity about all life on Earth.

In a paper published in the journal PLoS ONE, Boris Vinatzer proposes moving beyond the current biological naming system to one based on the genetic sequence of each individual organism. This creates a more robust, precise, and informative name for any organism, be it a bacterium, fungus, plant, or animal.

Vinatzer, an associate professor in the College of Agriculture and Life Science’s Department of Plant Pathology, Physiology, and Weed Science, suggests a new model of classification that not only crystalizes the way we identify organisms but also enhances and adds depth to the naming convention developed by the godfather of genus, Carl Linnaeus. Scientists worldwide have used the system that Linnaeus created for more than 200 years.
University of Massachusetts: ‘Oddball Science’ Has Proven Worth, Say UMass Amherst Biologists
February 27, 2014

AMHERST, Mass. ­– Scoffing at or cutting funds for basic biological research on unusual animal adaptations from Gila monster venom to snail sex, though politically appealing to some, is short-sighted and only makes it more likely that important economic and social benefits will be missed in the long run, say a group of evolutionary biologists at the University of Massachusetts Amherst.

Writing in a recent issue of BioScience, researchers Patricia Brennan, Duncan Irschick, Norman Johnson and Craig Albertson argue that “innovations often arise from unlikely sources” and “reducing our ability to creatively examine unique biological phenomena will ultimately harm not only education and health but also the ability to innovate, a major driver of the global economy.”

First author Brennan, known for her duck genitalia studies that could eventually aid human medical science points out, “Basic science has increasingly come under attack, and there is a growing perception that studying ‘odd’ science ideas with no clear societal benefits should be stopped. But we feel that these are the precise sorts of investigations that may lead to major innovations in biomedicine, technology and military applications.”
Humans and other Hominids

Science News: Human ancestors at West Asian site deemed two species
Disputed fossil study splits a pivotal early Homo species in two
by Bruce Bower
5:31pm, February 27, 2014
A controversial fossil and soil analysis concludes that a key West Asian site hosted not one but two Homo species, one living around 1.8 million years ago and another several hundred thousand years later.
Science Magazine: 'Little Foot' Fossil Could Be Human Ancestor
14 March 2014

PARIS—He may be called Little Foot, but for human evolution researchers he’s a big deal: His is the most complete skeleton known of an early member of the human lineage. Ever since the skeleton was discovered in a South African cave in the 1990s and named for its relatively small foot bones, researchers have been fiercely debating how old it is, with estimates ranging from about 2 million years to more than 3 million. A new geological study of the cave concludes that Little Foot is at least 3 million years old. If correct, that would mean he is old enough to be a direct ancestor of today’s humans, and could shift South Africa to the forefront of human evolution.
Heritage Daily: Paleo diet didn’t change – the climate did
Why were Neanderthals replaced by anatomically modern humans around 40,000 years ago?

One popular hypothesis states that a broader dietary spectrum of modern humans gave them a competitive advantage on Neanderthals. Geochemical analyses of fossil bones seemed to confirm this dietary difference.

Indeed, higher amounts of nitrogen heavy isotopes were found in the bones of modern humans compared to those of Neanderthals, suggesting at first that modern humans included fish in their diet while Neanderthals were focused on the meat of terrestrial large game, such as mammoth and bison.

However, these studies did not look at possible isotopic variation of nitrogen isotopes in the food resource themselves. In fact, environmental factors such as aridity can increase the heavy nitrogen isotope amount in plants, leading to higher nitrogen isotopic values in herbivores and their predators even without a change of subsistence strategy.
Artificial selection

Past Horizons: Aztec dog burials puzzle archaeologists
Article created on Saturday, February 15, 2014
During salvage excavations in Azcapotzalco (Northwest Mexico City), archaeologists from the National Institute of anthropology and history (INAH) discovered the remains of 12 dogs.

The dogs were placed there around 500 years ago, but unusually, without any apparent association to human burial - acting as a guide for the soul to the underworld, or as an offering dedicated to a temple or building.
LiveScience: Ancient Egyptian Kitten Skeletons Hint at Cat Domestication
By Stephanie Pappas, Senior Writer
March 17, 2014 07:51am ET
The skeletons of six cats, including four kittens, found in an Egyptian cemetery may push back the date of cat domestication in Egypt by nearly 2,000 years.

The bones come from a cemetery for the wealthy in Hierakonpolis, which served as the capital of Upper Egypt in the era before the pharaohs. The cemetery was the resting place not just for human bones, but also for animals, which perhaps were buried as part of religious rituals or sacrifices. Archaeologists searching the burial grounds have found everything from baboons to leopards to hippopotamuses.

The new find includes two adult cats and four kittens from at least two litters. The size of the bones and timing of the litters hints that humans may have kept the cats. The bones date back to between 3600 B.C. and 3800 B.C., which would be 2,000 years before the earliest known evidence of cat domestication in Egypt, archaeologists report in the May issue of the Journal of Archaeological Science.
Unnatural selection

Red Orbit: Evolution Of Conch Size Driven By Humans
Smithsonian Tropical Research Institute
March 19, 2014
The first humans to pluck a Caribbean fighting conch from the shallow lagoons of Panama’s Bocas del Toro were in for a good meal. Smithsonian scientists found that 7,000 years ago, this common marine shellfish contained 66 percent more meat than its descendants do today. Because of persistent harvesting of the largest conchs, it became advantageous for the animal to mature at a smaller size, resulting in evolutionary change.

Human-driven evolution of wild animals, sometimes referred to as “unnatural selection,” has only previously been documented under scenarios of high-intensity harvesting, like industrialized fishing. “These are the first evidence that low-intensity harvesting has been sufficient to drive evolution,” said lead author Aaron O’Dea of the Smithsonian Tropical Research Institute. “The reason may be because the conch has been subjected to harvesting for a long period of time.” Published March 19 in Proceedings of the Royal Society B, the findings are based on a comparison of mature shell sizes prior to human settlement, from shells excavated from human trash heaps representing various points in the last few thousand years and from modern sites.
Science Magazine: Why Did New Zealand's Moas Go Extinct?
March 17, 2014
For millions of years, nine species of large, flightless birds known as moas (Dinornithiformes) thrived in New Zealand. Then, about 600 years ago, they abruptly went extinct. Their die-off coincided with the arrival of the first humans on the islands in the late 13th century, and scientists have long wondered what role hunting by Homo sapiens played in the moas’ decline. Did we alone drive the giant birds over the brink, or were they already on their way out thanks to disease and volcanic eruptions? Now, a new genetic study of moa fossils points to humankind as the sole perpetrator of the birds’ extinction. The study adds to an ongoing debate about whether past peoples lived and hunted animals in a sustainable manner or were largely to blame for the extermination of numerous species.

“The paper presents a very convincing case of extinction due to humans,” says Carles Lalueza-Fox, an evolutionary biologist at the Institute of Evolutionary Biology in Barcelona, Spain, who was not involved in the research. “It’s not because of a long, natural decline.”

Scientists have long argued about what caused the extinction of many species of megafauna—giant animals including mammoths, mastodons, and moas—beginning between 9000 and 13,000 years ago, when humans began to spread around the world. Often, the animals disappeared shortly after humans arrived in their habitats, leading some researchers to suggest that we exterminated them by overhunting. But other scientists have pointed to natural causes, including volcanic eruptions, disease, and climate change at the end of last Ice Age, as the key reasons for these species’ demise. The moas present a particularly interesting case, researchers say, because they were the last of the giant species to vanish, and they did so recently, when a changing climate was no longer a factor. But did other natural causes set them on a path to oblivion, as some scientists proposed in a recent paper?
I could have put this section at the end to bring the entry full circle back to humans, but I have an ending I like better.

Non-hominid mammals

LiveScience: Ancient Whale Fossils Reveal Early Origin of Echolocation
By Tia Ghose, Staff Writer
March 12, 2014 02:00pm ET
An ancient whale used sound beams to navigate and stalk prey 28 million years ago, an analysis of a new fossil suggests.

The new whale species, called Cotylocara macei, contains air pockets in the skull similar to those used by porpoises and dolphins to send out focused sound beams. The discovery pushes back the origins of the ability, called echolocation, to at least 32 million years ago, said study co-author Jonathan Geisler, an anatomist at the New York Institute of Technology.

"It suggest echolocation evolved very, very early in the history of the group that involved toothed whales," a group that includes sperm whales and killer whales, as well as dolphins and porpoises, Geisler said.
LiveScience: Secret to Ancient Sloths' Aquatic Lives Found
By Laura Poppick, Staff Writer
March 11, 2014 09:49pm ET
Millions of years ago, aquatic sloths roamed shallow waters off the coast of modern-day Chile and Peru. These now-extinct swimmers had highly dense bones that facilitated their transition from land to sea by helping them sink to seafloors to graze on vegetation, according to a new report.

Only two groups of sloths exist today, both of which live in trees and grow to be the size of small monkeys. But during the Miocene and Pliocene — about 25 million to 4 million years ago — a great diversity of sloths crawled the Earth, including giant sloths that grew to be the size of elephants, and slightly smaller ones that spent time underwater.

Fossil remains suggest these aquatic sloths originated on land and gradually transitioned to life underwater. A series of fossil beds along the coast of Peru contain remnants of five different species of extinct sloths that researchers have interpreted to be aquatic based on the structure of their bones. For example, the density of their bones is much higher than the density of terrestrial mammal bones, but similar to bones of aquatic mammals that graze on seafloor vegetation, such as manatees.
Lewiston Tribune via the Ravalli Republic: Ancient bone near Lewiston, Idaho, may be from mammoth
By ELAINE WILLIAMS Lewiston Tribune
LEWISTON, Idaho – University of Idaho archaeologist Lee Sappington held two plastic Ziploc bags in his hands Wednesday containing the latest mystery for him to unravel.

Inside – sheathed in brown paper sacks – were fist-sized chunks of bone, which on the exterior looked very much like the rocks at his feet.
Other vertebrates

Uppsala University (Sweden) via Heritage Daily: Jawed vertebrates get a face
February 21, 2014
A  team of French and Swedish researchers present new fossil evidence for the origin of one of the most important and emotionally significant parts of our anatomy: the face.

They show how a series of fossils, with a 410 million year old armoured fish called Romundina at its centre, documents the step-by-step assembly of the face during the evolutionary transition from jawless to jawed vertebrates.

Vertebrates (backboned animals) come in two basic models: jawless and jawed. Today, the only jawless vertebrates are lampreys and hagfishes, whereas jawed vertebrates number more than fifty thousand species, including ourselves. It is known that jawed vertebrates evolved from jawless ones, a dramatic anatomical transformation that effectively turned the face inside out.
LiveScience: Mini Arctic T. Rex Relative Discovered
By Stephanie Pappas, Senior Writer
March 13, 2014 02:06pm ET
A miniature cousin of Tyrannosaurus rex once roamed the Arctic, a new fossil discovery reveals.

The new tyrannosaur (Nanuqsaurus hoglundi) had a skull length of between 23 and 27 inches (60 to 70 centimeters) when full-grown. In comparison, an adult T. rex boasted a skull about 60 inches (150 cm) long — that's a whopping 5 feet (1.5 meters).

"The 'pygmy tyrannosaur' alone is really cool because it tells us something about what the environment was like in the ancient Arctic," study researcher Anthony Fiorillo of the Perot Museum of Nature and Science in Dallas, said. "But what makes this discovery even more exciting is that Nanuqsaurus hoglundi also tells us about the biological richness of the ancient polar world during a time when the Earth was very warm compared to today."

LiveScience: Sponges May Have Breathed Life into Ancient Oceans
By Megan Gannon, News Editor
March 11, 2014 11:43am ET
You may owe your life to the lowly sea sponge.

Flourishing in extreme, deep-ocean environments hundreds of millions of years ago, sponges may have helped produce the oxygen requisite for the explosion of more complex life forms on Earth, a new study suggests.

"The effects we predict suggest that the first animals, far from being a passive response to rising atmospheric oxygen, were the active agents that oxygenated the ocean around 600 million years ago," study author Tim Lenton, a professor at the University of Exeter, said in a statement. "They created a world in which more complex animals could evolve, including our very distant ancestors."
LiveScience: 450-Million-Year-Old Marine Creatures 'Babysat' Their Young
By Becky Oskin, Senior Writer
March 13, 2014 01:43pm ET
The oldest fossil evidence of animal "babysitting" now comes from 450-million-year-old rocks in New York.

Small marine animals called ostracods, a group of crustaceans that includes more than 20,000 species living today, were discovered buried with their eggs and young by a team led by researchers from the University of Leicester in Britain. The findings were published today (March 13) in the journal Current Biology.

"This is a very rare and exciting find from the fossil record," David Siveter, lead study author and a geologist at the University of Leicester, said in a statement. "Only a handful of examples are known where eggs are fossilized and associated with the parent. This discovery tells us that these ancient, tiny marine crustaceans took particular care of their brood in exactly the same way as their living relatives."
Florida International University: Marine scientists identify lobsters’ ancestors
Posted by Evelyn Perez
02/25/2014 at 9:55 am
Scientists have long believed that lobster-like crustaceans first appeared on planet Earth about 360 million years ago. But FIU marine scientist Heather Bracken-Grissom contends the ancestor of our favorite mealtime decapod actually may have started roaming the planet at least 12 million years earlier.

Using fossil records and DNA testing, a team of international scientists led by Bracken-Grissom has determined the first lobster-like crustacean appeared on planet Earth approximately 372-409 million years ago.

“This is the most complete study of lobsters to date. One hundred and seventy-three species were analyzed, including commercially important species such as Maine lobster, Florida’s spiny lobsters and the redswamp crayfish, which Louisiana is famous for,” Bracken-Grissom said. “We also included some very rare species, recently discovered in the 1970s, who had never been included in an analysis before. It was interesting to include them because we got to see where they fell in the lobster tree of life.”
Bacteria and viruses

Virginia Tech: Discovery opens up new areas of microbiology, evolutionary biology
BLACKSBURG, Va., Feb. 7, 2014 – A team of researchers led by Virginia Tech and University of California, Berkeley, scientists has discovered that a regulatory process that turns on photosynthesis in plants at daybreak likely developed on Earth in ancient microbes 2.5 billion years ago, long before oxygen became available.

The research opens new scientific areas in the fields of evolutionary biology and microbiology. The work also has broad societal implications as it allows scientists to better understand the production of natural gas, and it sheds light on climate change, agriculture, and human health.

“By looking at this one mechanism that was not previously studied, we will be able to develop new basic information that potentially has broad impact on contemporary issues ranging from climate change to obesity,” said Biswarup Mukhopadhyay, associate professor of biochemistry at the Virginia Tech College of Agriculture and Life Sciences, one of the lead authors of the study. He is also an adjunct associate professor at the Virginia Bioinformatics Institute. Plant and microbial biology professor emeritus Bob B. Buchanan at University of California, Berkeley, co-led the research and co-authored the paper.
University of Michigan: Chemical chaperones have helped proteins do their jobs for billions of years
February 20, 2014
ANN ARBOR—An ancient chemical, present for billions of years, appears to have helped proteins function properly since time immemorial.

Proteins are the body's workhorses, and like horses they often work in teams. There exists a modern day team of multiple chaperone proteins that help other proteins fold into the complex 3D shapes they must achieve to function. This is necessary to avert many serious diseases caused when proteins misbehave.

But what happened before this team of chaperones was formed? How did the primordial cells that were the ancestors of modern life keep their proteins folded and functional?

Scientists from the University of Michigan discovered that an extremely simple, ancient chemical called polyphosphate can perform the role of a chaperone. It likely played that role billions of years ago, and still keeps its old job today.
LiveScience: Giant Virus Resurrected from Permafrost After 30,000 Years
By Tia Ghose, Staff Writer
March 03, 2014 03:00pm ET
A mysterious giant virus buried for 30,000 years in Siberian permafrost has been resurrected.

The virus only infects single-celled organisms and doesn't closely resemble any known pathogens that harm humans.

Even so, the new discovery raises the possibility that as the climate warms and exploration expands in long-untouched regions of Siberia, humans could release ancient or eradicated viruses. These could include Neanderthal viruses or even smallpox that have lain dormant in the ice for thousands of years.
Here's what escapefromwisconsin at The Hipcrime Vocab had to say about this discovery.
So this is where the zombie apocalypse virus might be found, spreading out from the arctic drilling rigs. Zombie science-fiction writers, fire up your keyboards!

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