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 on: Nov 24, 2015, 07:01 AM 
Started by Rad - Last post by Rad

Ok, let' continue on with our discussion and understanding of the transiting Lunar Nodes that have shifted in Pisces/ Virgo. Because the S.Node has moved into Pisces we can also discuss the transit of Neptune itself.

We have learned that the transiting S.Lunar Nodes correlates the parts of our past, the past of this or other lives, that the Soul is accessing during the transit of the S.Lunar Node in the time frame that it takes to go through whatever house. We have learned that this past is always shaping and defining the nature of each current moment as that moment interfaces with the yet undefined future. That dynamic tension between the past and the evolutionary future is experienced by us all is each moment: the nature of the 'moment' is the exact intersection, interfacing, between the past and the future. The transiting N.Node correlates to archetypes/ dynamics that symbolize and reflect the nature of what the evolutionary forces are that correlate to the unfolding future.

We now discuss another core archetype that correlates with Pisces, Neptune, and the 12th House that the transit of the Lunar S.Node, and the transit of Neptune in general, applies too. And that is one of culmination. Culmination of existing dynamics/ archetypes that have manifested in the life of the Soul, it's individual context, that are part of it's existing reality, the past leading to the moment, that are no longer necessary for the Soul to keep in place in terms of it's ongoing evolutionary needs.

Any glass can hold only so much water. So too with the Soul. There can only be so much that is part of it's reality at any point in time because, of course, water can overflow from the glass. So that which necessarily needs to culminate in order for something new to begin will be symbolized by house that the transiting S.Node is moving through, aspects to this Node from natal planets, the location of the natal Neptune by it's own house, sign, and aspects to it, and the location of the S.Node of Neptune by it's own house, sign, and aspects to it.

This very same thing can occur where the transit of Neptune is as well: by house, sign, and aspects to it.

The transiting N.Node in Virgo will then correlate, because of it's specific pull to the evolutionary future of the Soul, to the psychological experience that that which had been holding 'meaning before, the transit of the S.Node, no longer holds that meaning. That which is necessarily ending can now feel empty, meaningless, the inner sense of being 'done' with whatever it is. This then requires a Virgo adjustment to be made relative to that which is ending relative to that which wants to evolve: that which is new. That which is new that requires the adjustment is then symbolized by the house that the N.Node transit it is, the location of it's natal planetary ruler and all the aspects to it from other natal planets, and the location of the N.Node of Mercury by it's own house, sign, and aspects to it.

The adjustments necessary thus require what concrete, practical, necessary steps must be taken by the Soul to bring into actual reality that which the 'promises' of the new can be: the 'promise' is Pisces, Neptune, and the 12th house archetypes relative to the actual or concrete reality that the archetypes of Virgo, Mercury, and the 6th house as archetypes can make happen.

This very same thing can occur where the transit of Neptune is as well: by house, sign, and aspects to it. And because it is Pisces now the natural polarity of Virgo applies in the very same was as does the N.Node of the Lunar Node in Virgo.

So now reflect on your own charts to objectify and understand these things. If you have any questions please ask them of me now before we move on.

God Bless, Rad

 on: Nov 24, 2015, 06:31 AM 
Started by Rad - Last post by Rad
CS Monitor

Mexican gray wolf's reintroduction shows shifting views on conservation

The Mexican gray wolf almost disappeared in the 1970s. But four decades later, its reintroduction to the wild still spawns controversy and sheds light on mankind's changing perspectives on policy.

By Michael D. Regan, Staff November 24, 2015   

It has been four decades since the Mexican gray wolf nearly fell to extinction.

Ostracized as vermin and portrayed as man-killers, they once numbered in the thousands before almost disappearing.

Yet, despite a 1998 federal plan for reintroduction to Arizona and New Mexico, the largest gray wolf species remains one of the most endangered animals in the world.
Recommended: Name that animal!

The reintroduction plan for the Mexican gray wolf called for bolstering the number living in the wild to 100 by 2006. The program has had some success, even as it has fallen considerably short of those initial projections.

The latest government statistics show roughly 110 wolves are now living in the wild. Among those, eight breeding pairs can be found in Gila and Apache national forests spanning the two Southwest states.

After decades of depleted numbers, many wolf species are making a slow comeback despite some opposition to their reintroduction.

The controversial topic represents a shift in the perception that wolves represent a danger to mankind. More recent disapproval seems to stem from fears over the killing of livestock, leaving a tangle of state and federal policies.

Many Americans now believe wolves are an important part of the North American ecosystem and as a society there is an ethical imperative to protect them. Polling has shown surging approval for the preservation of wolves.

Seventy percent of Americans believe wolves are an integral “part of American wilderness and natural heritage,” according to a national survey conducted in 2013 by Public Policy Polling. More than 50 percent of those polled said they would like to see a wolf in the wild.

Yet as national discussions turns from elimination to preservation, the reality on the ground in many states is more complicated, as the tug of differing opinions continues to play out between government, ranchers, conservation groups, and concerned citizens.

Political discourse can also influence policies linked to wolves. A program launched in 1995 to bring wolves back to the wild in Yellowstone National Park has often been held up as a benchmark for reintroduction, notwithstanding 2012 Congressional efforts to delist them as an endangered species.

As of 2014, 104 wolves were living in 11 packs in Yellowstone, while the number of livestock killed by wolves fell well below US National Park Service estimates.

While many ranchers continue to fervently object to programs favoring reintroduction of wolves to the wild because of concerns over the loss of livestock, some have taken a more holistic approach.

A group called the Range Riders now guard a bucolic valley in central Washington State, where wolves were introduced in 2011, using a combination of technology and horseback patrols meant to keep livestock safe.

“I’m not excited about it,” said local rancher Sam Kayser to Capital Press, a weekly publication. “But it doesn’t matter if I’m excited. We’re stuck with them. I want to think there’s room for all of us."

But even with the backing of the federal government, reintroducing wolves doesn’t always have an easy solution. A permit request by the US Fish and Wildlife Service to reintroduce the Mexican gray wolf into parts New Mexico this year was denied by the state-controlled New Mexico Department of Fish and Game, the Albuquerque Journal reported.

The FWS announced in mid-October it would use its federal authority to subvert opposition and push to install the wolf recovery program, according to the Journal.

Yet reintroducing wolves and other species remain essential to their recoveries, according to New Mexico’s Center of Biological Diversity, an advocacy group pushing for an increase in state’s biodiversity.

“Releasing Mexican wolves to the wild is the only way to save these animals from extinction,” said one of the group’s advocates, Michael Robinson, to the Journal. “It’s vital now that enough wolves get released to diversify their gene pool and ensure they don’t waste away from inbreeding.”

 on: Nov 24, 2015, 06:29 AM 
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CS Monitor

Where did humans turn wolves into domesticated dogs?

Researchers have traced the origins of canine domestication, aka Canis lupus familiaris, back to Central Asia.

By Eva Botkin-Kowacki, Staff writer November 24, 2015   

In many human households today, dogs are running partners, hunting buddies, and cuddly best friends. But it hasn’t always been that way.

Thousands of years ago, the domestic dog, Canis lupus familiaris, did not exist. But, over time, human and wolf interactions somehow produced humanity's first domesticated animal.

Scientists have been working to unravel the mysterious origins of dogs for years. Now, they may know where it all began.

Previous studies have suggested canine domestication occurred in locations such as the Middle East, Europe or southern China, the first dogs may have actually emerged in Central Asia, according to a new study out of Adam Boyko Laboratory at the Cornell University College of Veterinary Medicine.

“There’s a lot of debate about when it happened and why it happened,” says study author Adam Boyko. “I think the first thing you need to answer is where it happened,” he told The Christian Science Monitor in an interview.

“Narrowing it down to where is the first step in coming up with a comprehensive theory of what was going on,” says Dr. Boyko. And Central Asia seems to be the spot.

The paper, published Monday in the journal Proceedings of the National Academy of Science, focuses on village dogs, populations of dogs that live around human communities but not in people’s homes. Boyko describes these canines as “semi-feral street dogs.” They are generally found in rural areas today.

With nobody controlling the pooches’ breeding, the genetic patterns in these modern populations most closely resemble natural historic populations. From these village dogs, the researchers can better identify wolf ancestry.

The scientists sampled DNA from populations of village dogs across the globe. They compared markers in these dogs’ genomes to home in on the clearest descendants of the original domesticated dogs. Populations in rural Central Asia, especially in countries like Nepal and Mongolia, arose as those special hounds.

Not the only region in the spotlight

Scientists have pointed to other regions for canine domestication too.

Peter Savolainen, an associate professor of evolutionary genetics at the Royal Institute of Technology (KTH) in Stockholm, Sweden has done extensive research that points to Southeast Asia, specifically Southern China, as the setting for dog domestication instead.

Dr. Savolainen points out that this new paper does not include samples from Southern China. “If they don’t believe it is South China, then they should, in their own research, try to disprove it,” he told The Christian Science Monitor in an interview.

Boyko agreed that more samples from more places will be necessary to narrow down a location, but, he says, “We had dozens of samples from North Vietnam, within kilometers of the Chinese border.”

“Unless there’s a huge barrier to gene-flow between China and Vietnam, which I don’t see any evidence to suggest that there would be, I’m pretty convinced that the diversity signatures we’re seeing are implicating a more western origin,” Boyko explains.

Still, both researchers are pleased that their results are nearby each other.

“To me that’s reassuring, that we’re homing in on similar areas,” Boyko says.

Savolainen agrees, “It’s obviously some kind of a consensus now in our two studies,” with the focus on Asia.

Both researchers are planning further work to narrow down that wide field and hope to incorporate archeological research as well.

Chasing the tale of domestication

Dogs were the first human domesticated animals, but humans may not have intentionally made these furry friends.

A prominent hypothesis is that the wolves themselves wandered into human camps to scavenge from scrap piles. In this scenario, it was the wolves who carried genes to be less afraid of humans that had an evolutionary advantage. Over time, a wolf population grew that was tamer and more comfortable co-existing with humans.

Perhaps people saw these animals as useful companions when they wandered in and domestication became more of a mutual process, but scientists aren’t sure when, why or how it all happened.

What the true story is, “Nobody knows, because it’s impossible to know exactly what happened in that time,” says Savolainen.

But finding where this first domestication event played out could lead researchers to archeological or other clues about those early dog populations and the humans they befriended.

Why Fido’s ancestors matter to humans

“I think it tells us something about the story of people,” says Boyko. As the first domesticated animal, the history of dogs is linked with our own background.

Savolainen explains, “The history of dogs is very closely related to the history of humans. They were our first domestic animals and they follow us everywhere in the world, to every continent.”

“It’s a way at looking at human history,” he says of studying canine domestication. “You can also follow human migrations by following the dogs.”

Simply put, “it’s history” that makes dogs’ story significant, says Savolainen. “So if you think history is important, then it’s important,” he says. “Otherwise, it’s not.”

 on: Nov 24, 2015, 06:22 AM 
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CS Monitor

Wildlife thriving in abandoned Chernobyl zone

Three decades after the world's worst nuclear disaster, the exclusion zone around the remains of the Chernobyl nuclear power plant has become a haven for wildlife.

By Kate Kelland, Reuters 11/24, 2015   

London — Some 30 years after the world's worst nuclear accident blasted radiation across Chernobyl, the site has evolved from a disaster zone into a nature reserve, teeming with elk, deer and wolves, scientists said on Monday.

The remarkable turnaround in the area, which was declared a permanent no-go zone for people after the accident in 1986, suggests radiation contamination is not hindering wildlife from breeding and thriving, but underscores the negative impact humans have on populations of wild mammals.

"When humans are removed, nature flourishes - even in the wake of the world's worst nuclear accident," said Jim Smith, a specialist in earth and environmental sciences at Britain's University of Portsmouth. "It's very likely that wildlife numbers at Chernobyl are now much higher than they were before the accident."

After a fire and explosion at the Chernobyl nuclear power plant in 1986 threw clouds of radioactive particles into the air, thousands of people left the area, never to return.

Smith and co-researchers took the opportunity to see what happens to wildlife in an area where contamination is heavy but people are largely absent.

Earlier studies in the 4,200 square kilometer (1,600 square miles) Chernobyl Exclusion Zone showed major radiation effects and pronounced reductions in wildlife populations.

But new evidence, based on long-term census data, shows that mammal populations have bounced back.

The study found a relative abundance of elk, roe deer, red deer and wild boar -- with population rates similar to those found in four designated, and uncontaminated, nature reserves in the region. The number of wolves living in and around the Chernobyl site is more than seven times greater than can be found in comparable nature reserves.

And helicopter survey data also reveal rising trends in the abundance of elk, roe deer, and wild boar from 1 to 10 years after the accident.

"These unique data showing a wide range of animals thriving within miles of a major nuclear accident illustrate the resilience of wildlife populations when freed from the pressures of human habitation," said Jim Beasley of the University of Georgia in the United States, who co-led the work.

The results, published in the journal Current Biology, may also hold lessons for understanding the potential long-term impact on wildlife of the more recent Fukushima nuclear accident in Japan, the researchers said. (Reporting by Kate Kelland; Editing by Ruth Pitchford)

CS Monitor

After three decades, is Chernobyl now a haven for wildlife?

Nearly 30 years after the Ukraine nuclear disaster that forced thousands of people from their homes researchers find the animals are back - and thriving.

By Eva Botkin-Kowacki, Staff writer October 5, 2015   

When a reactor at the Chernobyl Nuclear Power Plant in Ukraine exploded on April 26, 1986, radioactive dust settled over thousands of miles. The next day some 116,000 people were evacuated, thinking they would return home just days later. They never did.

Now nearly 30 years later, villages and cities in the 1,600-square-mile exclusion zone sit empty. Pripyat, once a city of 50,000 nearby Chernobyl, is a crumbling ghost town.

But the zone isn’t truly empty. In the absence of humans, the animals seem to have taken over, say researchers.

The overgrown exclusion zone is teeming with animals. Populations of animals such as wild boar, roe deer, and wolves have rebounded immensely, according to a study published Monday in the journal Current Biology.

Humans leaving the area could have been the best thing for these animals, says study author Jim Smith of the University of Portsmouth in the UK. “That’s not saying radiation is good for animals, but human habitation, occupation, agriculture, forestry is worse,” he says in an interview.

The exclusion zone, the region evacuated following the Chernobyl fire and explosion, stretches across the border of Ukraine and Belarus. The data used in this study comes from the Polessye State Radioecological Reserve in Belarus, which encompasses about half of the exclusion zone.

Researchers at the reserve counted elk, wild boar, and roe deer from helicopter flights throughout 1987 and 1996. They saw the population of these large mammals grow dramatically in the years immediately following the nuclear disaster.

For example, says Dr. Smith, “The wild boar initially increase very rapidly in population numbers. That was due to the good conditions for them. The people had moved out, they were recolonizing the area, there was abundant food supplies.”

The boar picked up where the people had left off, in a way. “There were crops left, orchards, vegetable gardens and so on,” Smith says. “There’s evidence of [the boar] occupying the villages and the farms in the area. Ironically, some of the farm buildings where the pigs used to stay, they were moving back in.”

As part of the study, researchers compared the abundance of certain mammals in Chernobyl to those in other nature preserves in Belarus. They found that Chernobyl held just as many of these animals as the other protected sites.

In fact, there were more wolves in Chernobyl than in the other reserves. Smith suggests that with much less human traffic and more distance from human communities the wolves have seen less hunting and other threats.

Other researchers have found animals, like wild boar, as far away as Germany to be radioactive decades after the nuclear explosion. But Smith doesn’t think the contamination is significantly influencing the size of these animals’ populations.

Smith looked at data from snow-track surveys gathered from 2008 to 2010 by the Belarusian researchers. “There are 35 routes, each of about 9 kilometers, where they count the number of animal tracks. Those pretty much cover the whole of the exclusion zone in Belarus,” he says.

Smith says, “We mapped out those routes and worked out the radioactive contamination density on each of those routes to see, once we’ve accounted for different habitat along the routes, can we see an influence of the radioactive contamination on the number of tracks we’re counting. And we couldn’t.”

Sure, some individual animals could be affected by the remaining radioactive hotspots, but on an overall population level the animals seem to be thriving, says Smith.

“We’re not saying radiation is good for them. We’re also not saying that there aren’t some individual level effects. There might be,” he says. But “We’ve looked at the population and we don’t see an effect.”

 on: Nov 24, 2015, 06:20 AM 
Started by Rad - Last post by Rad

CS Monitor

Ancient 'hypercarnivores' preyed on mammoths, say scientists

A million years ago, giant predators like the cave hyena and the saber-toothed cat were able to take down mastadons, according to new computer models.

By Charles Q. Choi, LiveScience Nov 24, 2015   

Nearly a million years ago, a cave hyena could have taken down a 5-year-old mastodon weighing more than a ton. And in packs, the predators may have been equipped to demolish a 9-year-old mastodon weighing a hefty 2 tons.

That's according to new computer models that can calculate how big a target an ancient hypercarnivore, such as the cave hyena and the saber-toothed cat that rely solely on meat for sustenance, might have tackled, researchers say.

These findings show how ancient super-predators far larger than the wolves, lions and hyenas of today once kept megaherbivores such as mammoths, mastodons and giant ground sloths in check, researchers said.

Photos: Autopsy of a 40,000-Year-Old Mammoth...

"The probable role these large predators played in maintaining stable ecosystems hasn't been recognized until now," said the study's lead author, Blaire Van Valkenburgh, an evolutionary biologist at the University of California, Los Angeles.

Nowadays large herbivores such as elephants and white-tailed deer can have devastating effects on the environment by stripping it of vegetation through overgrazing (eating ground plants) or overbrowsing (eating leaves off trees). This brings up the question of what prevented widespread habitat destruction in the Pleistocene epoch, which lasted from about 1 million to 11,000 years ago. Back then, a much greater diversity of megaherbivores — plant-eaters 1,760 lbs. (800 kilograms) and larger — roamed the Earth.

Modern research suggests that current megaherbivores like elephants are largely immune to predators. However, scientists now find that ancient hypercarnivores had the ability to, and likely did, limit megaherbivore numbers.

The impact of ancient hypercarnivores on past megaherbivores may have been difficult to appreciate because many extinct hypercarnivores such as saber-toothed cats have no close living counterparts, the researchers noted. This makes it difficult to deduce what they might have preyed on.

Still, the researchers noted there was once a much greater diversity of predators than exists today, many of which were significantly larger than their modern analogs — for the ones that do have analogs. This diversity suggests there was once intense competition between these carnivores, perhaps leading some to specialize in hunting megaherbivores.
Pleistocene teeth

To deduce the potential impact of ancient hypercarnivores, the researchers analyzed the fossil record to gauge size ranges for Pleistocene predators larger than about 45 lbs. (21 kg). Whereas modern hypercarnivores average 116 to 138 lbs. (53 to 63 kg), fossil hypercarnivores spanned 211 to 297 lbs. (96 to 135 kg) on average.

"Scientists didn't really understand how much bigger some of these Pleistocene predators were than modern ones," Van Valkenburgh told Live Science.

Previous research then helped the scientists develop estimates of an animal's size based on just its first molar. "In the fossil record, the one thing we've got a lot of is teeth," Van Valkenburgh said in a statement.

The researchers next estimated the sizes of ancient mammoths and mastodons. To do so, they developed mathematical formulas for the relationship of shoulder height to body mass from previous research on modern captive elephants.

By looking at the sizes of modern carnivores and the preferred sizes of their victims, the scientists then estimated what sizes of prey ancient predators might have targeted. They concluded that juvenile mastodons and mammoths would have been susceptible to many past hypercarnivores, especially ones that hunted in groups such as prides, clans and packs.

Indirect evidence that ancient predators hunted in larger groups than they do today may come from fossil teeth. Among modern carnivores, when competition over prey is high, prey is more difficult to capture, and carnivores make the most out of carcasses by eating more bone, leading to higher rates of broken teeth. When it came to large predators of the New World during the Pleistocene, tooth fracture rates were as much as three to five times that of their modern counterparts, suggesting higher densities of predators to prey than seen now.

"The group sizes of predators were considerably larger in the past than they are today, which would have made it easier for them to take down large prey," Van Valkenburgh said.

More work is needed to reconstruct Pleistocene ecosystems, "which were clearly hugely different from today," Van Valkenburgh said. "By understanding what we lost, what the productivity of the planet was, we can learn more about the time in which our species evolved and maybe why we've done so well."

Van Valkenburgh and her colleagues detailed their findings online today (Oct. 26) in the journal Proceedings of the National Academy of Sciences.

 on: Nov 24, 2015, 06:17 AM 
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CS Monitor

New beetle species may already be endangered

A new whirligig beetle was recently discovered, and due to its particular habitat requirements, it may already need protection.

By Annika Fredrikson, Staff November 24, 2015   

A scientist has discovered a new species of whirligig beetle, the first new whirligig cataloged in more than two decades.

Grey Gustafson, a PhD student at the University of New Mexico, discovered these in April while hunting for a species in a different genus. Noticing the beetles looked a bit different, Mr. Gustafson collected a few samples.

A few months later, Gustafson confirmed his species was the same as 11 specimens kept at the Enns Entomology Museum at the University of Missouri. Collected in the 1970s, the specimens were never named nor confirmed as a new species.

In his new paper in the Annals of the Entomological Society of America, Gustafson describes the male and female beetles in detail, highlighting how these Dineutus shorti beetles differ from the previously known Dineutus discolor species.

Whirligig beetles are found in streams across the southern United States, but D. shorti lives only in areas with longleaf pines, including Conecuh National Forest in Alabama and Blackwater River State Park in Florida.

Gustafson argues D. shorti may live only in a narrow region in the Florida panhandle and southern Alabama.

"Longleaf pine forests once dominated the southern coastal plains region, but have been severely diminished, negatively affecting endemic species," writes Gustafson in his paper. "If D. shorti is restricted to areas of old-growth longleaf pine, and given the predicted loss of habitat within the region, this new species may already be worthy of formal protection status."

Biologists consider the Florida panhandle one of North America’s five richest biodiversity hotspots, so it’s no wonder that a new species was discovered here, and that more species probably await discovery, says Gustafson.

"That a large, charismatic beetle remained hereto undiscovered highlights the obvious need for increased surveys of the aquatic invertebrates of this region in order to discover unrecognized biodiversity, including other species of conservation concern," he writes.

 on: Nov 24, 2015, 06:14 AM 
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CS Monitor

What do trees tell us about climate change?

A researcher uses tree-rings to map droughts and downpours throughout history.

By Eva Botkin-Kowacki, Staff writer November 24, 2015      

Trees don’t just provide the paper for history books. They actually write the historical records themselves.

Tree-rings, new layers of wood added to a growing tree each year, record climatic data annually throughout a tree’s life. Ancient trees provide a record of drought, rainfall, and other climatic variations. And that record could help scientists better understand current and future climate trends.

Dendrochronologist Edward R. Cook and his team at the Lamont-Doherty Earth Observatory of Columbia University have been working to map ancient droughts and downpours in forests across the globe, using the trees themselves as a guide. His latest map, the Old World Drought Atlas, covers Europe, the Middle East, and the Mediterranean rim of Africa, as described in a paper published Friday in the journal Science Advances. Previously, Cook and his colleagues created the North America Drought Atlas and the Monsoon Asia Drought Atlas.

“Trees give us exactly dated annual records of climate variability,” Cook tells The Christian Science Monitor in an interview. Each ring represents a year of growth and trees grow differently depending on rainfall, temperature, and other climatic factors.

“A narrow ring would mean that it was a dry year and a wider ring would indicate better moisture conditions for growth,” Cook explains. So a drought year would produce a narrower ring.

“There are other measures in the tree-rings that can also provide other climate information. Sometimes you look at wood density changes, for example, and that can reflect how warm or cold it is during the summer growing season,” says Cook. A warmer summer will produce more dense wood in the year’s ring.

These tree rings also match climate extremes documented by humans.

The rings that align with the Great Famine of 1315 to 1317 in Europe tell a tale of oversaturated crops. Documented history suggests that the famine was caused by wet conditions that led to massive crop failure. “The tree-rings reflect that beautifully,” says Cook.

“The kind of information you can get from the drought atlas also informs us about the climate conditions associated with historical events in the past,” he says.

Across all three drought atlases, Cook and his colleagues noticed a period of megadroughts, prolonged dry periods, about one thousand years ago during the Medieval period. This dryness seems to have been natural variation.

But, says Cook, with greenhouse-gas-induced climate change already warming and drying many regions across the globe, the tendency for megadroughts to occur naturally as well could mean compounding droughts.

Cook hopes that his drought atlases will help scientists better understand the mechanisms involved in drought.

Tree rings are called rings because they appear as concentric circles on the stump of a tree when it’s chopped down. But, says Cook, “We don’t kill trees to extract this information.”

Instead, the scientists take just a sliver of the tree to examine. “We use a device called a Swedish increment borer that extracts a long dowel-like piece of wood from the tree, about five millimeters in diameter,” Cook says. That core of wood displays all the rings, the entire life-history of the tree.

“This does not damage the tree in any meaningful way,” Cook says. In fact, Cook has returned to trees he sampled 20 years earlier to sample them again. And, he says, “the tree lives on for many many years after that.”

“Trees are remarkable living things out there that are like rain gauges and thermometers sitting out there for decades,” or more, Cook says. “They’re one of the most remarkable terrestrial organisms in the world.”

 on: Nov 24, 2015, 06:12 AM 
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CS Monitor

How did a canine hybrid, ‘coywolf,’ emerge in front of our eyes?

A hybrid of coyote, wolf and dog that has developed over the last century or so, has many advantages over the purebred versions.

By Lonnie Shekhtman, Staff November 24, 2015   

It seems that a hybrid of coyote, wolf, and dog DNA makes for a potent mix, as scientists have observed in a fit, new canid family member that’s been spreading through the eastern part of North America.

The “coywolf” – also known as the coydog, the eastern coyote, the tweed wolf, the brush wolf, the northeastern coyote, or the new wolf – was first described by scientists in the 1960s. Its population has quickly grown to millions and is quickly expanding into the southeast, drawing on the most advantageous features of each of the canid members that make up its hybridized DNA to spread and flourish in areas that have traditionally been inhospitable to purebred coyotes and purebred wolves.

“We’ve known for a while that most Eastern coyotes are hybrids to some degree, and now we’re finding a greater degree of hybridization than anyone expected,” Javier Monzón, an evolutionary biologist at Pepperdine University, told The Washington Post last year.

Dr. Monzón studied the genetic makeup of 427 of the animals in ten northeastern states and Ontario, concluding in a 2013 paper that coywolves are about 62 percent coyote, 27 percent wolf and 11 percent dog.

This mix brings big advantages, reports The Economist, as coywolves are twice as big as coyotes, with larger jaws, more muscle and faster legs. One coywolf could take down a small deer, while a pack of them can likely kill a moose.

Banking on its wolf-inspired love for hunting, coywolves can catch prey in both open terrain and densely wooded areas, “And even their cries blend those of their ancestors,” reports the Economist. “The first part of a howl resembles a wolf’s (with a deep pitch), but this then turns into a higher-pitched, coyote-like yipping.”

The DNA coywolf has inherited from man’s best friend may have counteracted its wolf instinct to avoid humans, some scientists believe, allowing it to spread and thrive among the people and noise of urban areas, where it can now commonly be found.

Roland Kays, director of the biodiversity lab at the North Carolina Museum of Natural Sciences told the Economist that this is an “amazing contemporary evolution story that’s happening right underneath our nose.”

Biologists suspect that the interbreeding that led to the coywolf began a century or two ago, when wolf populations in southern Ontario began declining as humans began clearing their forest habitat for farming, and to being killed in retaliation or anticipation of their deadly interactions with the humans who took over their land.

Deforestation simultaneously allowed coyotes that had previously lived in the plains between the Rocky Mountains and the Mississippi River to migrate northeast where they encountered attractive breeding partners in what was left of the wolves and in farmers’ dogs.

And thus the coywolf was born.

This type of hybridization among mammals has rarely been documented, reported Jonathan G. Way, a research scientist at Clark University, in a 2013 paper in The Canadian Field-Naturalist journal. Though it’s common among amphibians, insects, birds, plants and fish.

Dr. Way says that the coywolf has evolved into a new species, arguing that its morphological and genetic branching off from its ancestors qualifies it for its own label.

But the verdict is still out among scientists. As the the Economist reports, one species is commonly defined as a population that doesn’t interbreed with outsiders. Since coywolves continue to mate with dogs and wolves – mammals that are all in the Canis genus – they may be a subspecies, not a separate species.

 on: Nov 24, 2015, 06:10 AM 
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CS Monitor

Why did those giant rats go extinct? And could they come back?

Thousands of years ago in what is today East Timor, humans shared the forest with rats the size of small dogs.

By Lonnie Shekhtman, Staff November 24, 2015   

“Rodents of unusual size? I don’t think they exist,” says Westley, the young heroic lead in "The Princess Bride," an instant before he gets tackled by a rat the size of a bear.

Turns out the 1987 cult classic film has some reality behind it. Though a bear-size rat hasn’t yet materialized in archeology, fossils from the largest rat ever were recently discovered by researchers from the Australian National University (ANU). About the size of a miniature dachsund, it used to live alongside humans on the Southeast Asian island nation of East Timor thousands of years ago, they said.

ANU scientists are now trying to determine why the rats vanished about a thousand years ago. They suspect humans, which seem to have first moved through the Southeast Asian islands 46,000 years ago, had something to do with it.

“The reason we think they became extinct is because that was when metal tools started to be introduced in Timor [and] people could start to clear forests at a much larger scale," said ANU paleontologist Julien Louys in a statement online.

The research team said that the information it is gathering on how humans interacted with and affected their environment on the islands over thousands of years can be used to inform modern conservation efforts.

“We're trying to find the earliest human records as well as what was there before humans arrived," Dr. Louys said.

He added, "Once we know what was there before humans got there, we see what type of impact they had."

The Australian team discovered the fossils of seven species of these giant rats recently while trying to map the earliest human movement through Southeast Asia as part of a project called “From Sunda to Sahul.”

The biggest rats, they reported in a statement, were the size of a small dog, 10 times bigger than the rodents we’re familiar with today.

It seems that humans not only lived alongside the beastly rats thousands of years ago, they also ate them, researchers report.

“We know they're eating the giant rats because we have found bones with cut and burn marks," Louys said.

Though the giant rat is an impressive new discovery, it’s certainly not the most astonishing example of a modern animal that has shrunk over millennia by evolutionary forces to a more manageable size (as far as humans are concerned).

In 2009, paleontologists discovered fossils of a school-bus-length relative of a boa constrictor in Colombia. Its 2,500 pounds were expected to have slithered through the Amazonian forest about 60 million years ago, after the dinosaurs died out.

But there are giants still among us today who survived mass extinctions, one of which wiped out the dinosaurs 65.5 million years ago.

Namely, the blue whale, the largest known animal to have ever lived. Some have been recorded at about 100 feet long, though 70 to 90 feet is the average length. That’s the length of three school buses. They weigh about 200,000 to 300,000 pounds.

There’s also the American bison, elephants, and rhinos, as Slate pointed out.

Scientists believe that bulk can confer evolutionary advantages, reports Slate. Bigger animals don’t need to worry about predators so much and can beat out all others for resources. Prodigious size can help warm-blooded animals retain heat in cold climates, or alternatively, it can help insulate cold-blooded animals and keep them from overheating in hot climates.

And it could bring giants back. It took 15 million years for giant mammals to come back after the dinosaurs died; the last major extinction happened about 12,000 years ago. If giant rats ever roam the Earth again, it likely won't be for a very long time.

 on: Nov 24, 2015, 06:05 AM 
Started by Rad - Last post by Rad
CS Monitor

Rivers may have once criss-crossed the Sahara, say scientists

Researchers map an ancient river system hidden deep under the sands of the western Sahara desert.

By Eva Botkin-Kowacki, Staff writer November 24, 2015   

Today, the Sahara is thousands of miles of hot, dry sand stretching across northern Africa. But it hasn’t always been that way.

Thousands of years ago, a vast river system flowed through the western Sahara.

Researchers found markers of these ancient rivers buried beneath the sand dunes, according to a new study published Tuesday in the journal Nature Communications.

Previous research had found evidence of such a river network in marine sediment. Rocks and other materials characteristic of a riverbed had been deposited on the oceanic coast, just as a river delta would push its contents into the sea.

Researchers had also discovered a submarine canyon in the continental shelf off the coast of western Africa. Dubbed Cap Timiris Canyon, the underwater corridor also suggested the past existence of a river system in the western Sahara.

But the origins of those sediments and the river that fed the channel had yet to be mapped. Using orbital radar satellite imagery, Charlotte Skonieczny of the L'Institut Français de Recherche pour l'Exploitation de la Mer and her colleagues looked beneath today’s bone-dry, sandy desert to geological features beneath. These ancient features helped them map a river system some 320 miles long that lines up perfectly with the sediments and underwater canyon.

“In this paper, based on remote-sensing data, we identify the presence of a large paleodrainage network on the arid Mauritanian coast, shallowly buried at present under aeolian sediments,” Dr. Skonieczny and her colleagues write. “Combined with other geomorpholgical and sedimentary lines of evidence available in the literature, our findings suggest that a major river system was indeed reactivated during some of the humid periods of the last 245 kyrs, thus likely contributing to the delivery of sediments to the Tropical Atlantic margin at those times.”

Starting some 245,000 years ago, a series of humid periods began. During these periods, rainfall shifted over the western Sahara, making the region wetter. That extra rain likely pooled in Mauritania and Algeria before spilling down rivers to the Mauritanian coast and into the ocean.

"At that time," write the researchers in an email to The Christian Science Monitor, "equatorial lakes reached their highest level and the present-day Saharan desert was the location of extensive vegetation, animal life and human settlements."

The Sahara's climate shift was driven by subtle variations in the Earth's orbit around the sun, the researchers say. That such a drastic shift could arise from such minute variations in sunlight is "Yet another reminder," the researchers write, "in the context of the growing greenhouse gases emissions (another external forcing), of how sensitive the climate system is."

Researchers have often looked for evidence of ancient rivers across the Sahara desert in the hopes of mapping humans’ trek out of Africa.

Scientists puzzled over how humans migrated from Central Africa to the Middle East, Europe, and Asia with a massive arid desert in their way. It would have been inhospitable, or so they thought.

A study published in 2013 mapped evidence of ancient riverways up through what is present-day Libya. Those rivers likely would have created some more lush places for the ancient humans.

These findings could help modern-day humans find water. "This large paleo-river system is likely to be related to large amount of fossil water resources in shallow aquifers located where the channels were mapped," the authors write in their email. "This gives then some interesting geographical information on where to drill for finding some new water resources in desert regions."

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