Triassic dinosaurs avoided the tropics


This video from the USA says about itself:

15 January 2009

A team of paleontologists from the University of California, Berkeley, the American Museum of Natural History and The Field Museum discovered fossils in northern New Mexico that show for the first time that dinosaurs coexisted with their non-dinosaur ancestors for tens of millions of years towards the end of the Triassic Period. This discovery, made at the Hayden Quarry in Ghost Ranch, New Mexico, disproves previous notions that dinosaurs rapidly replaced their supposedly outmoded predecessors.

From the National Science Foundation in the USA:

Big dinosaurs steered clear of the tropics

Climate swings lasting millions of years too much for dinos

June 15, 2015

For more than 30 million years after dinosaurs first appeared, they remained inexplicably rare near the equator, where only a few small-bodied meat-eating dinosaurs made a living.

The long absence at low latitudes has been one of the great, unanswered questions about the rise of the dinosaurs.

Now the mystery has a solution, according to scientists who pieced together a detailed picture of the climate and ecology more than 200 million years ago at Ghost Ranch in northern New Mexico, a site rich with fossils.

The findings, reported today in the journal Proceedings of the National Academy of Sciences (PNAS), show that the tropical climate swung wildly with extremes of drought and intense heat.

Wildfires swept the landscape during arid regimes and reshaped the vegetation available for plant-eating animals.

“Our data suggest it was not a fun place,” says scientist Randall Irmis of the University of Utah.

“It was a time of climate extremes that went back and forth unpredictably. Large, warm-blooded dinosaurian herbivores weren’t able to exist close to the equator–there was not enough dependable plant food.”

The study, led by geochemist Jessica Whiteside, now of the University of Southampton, is the first to provide a detailed look at climate and ecology during the emergence of the dinosaurs.

Atmospheric carbon dioxide levels then were four to six times current levels. “If we continue along our present course, similar conditions in a high-CO2 world may develop, and suppress low-latitude ecosystems,” Irmis says.

“These scientists have developed a new explanation for the perplexing near-absence of dinosaurs in late Triassic [the Triassic was between 252 million and 201 million years ago] equatorial settings,” says Rich Lane, program director in the National Science Foundation’s (NSF) Division of Earth Sciences, which funded the research.

“That includes rapid vegetation changes related to climate fluctuations between arid and moist climates and the resulting extensive wildfires of the time.”

Reconstructing the deep past

The earliest known dinosaur fossils, found in Argentina, date from around 230 million years ago.

Within 15 million years, species with different diets and body sizes had evolved and were abundant except in tropical latitudes. There the only dinosaurs were small carnivores. The pattern persisted for 30 million years after the first dinosaurs appeared.

The scientists focused on Chinle Formation rocks, which were deposited by rivers and streams between 205 and 215 million years ago at Ghost Ranch (perhaps better known as the place where artist Georgia O’Keeffe lived and painted for much of her career).

The multi-colored rocks of the Chinle Formation are a common sight on the Colorado Plateau at places such as the Painted Desert at Petrified Forest National Park in Arizona.

In ancient times, North America and other land masses were bound together in the supercontinent Pangea. The Ghost Ranch site stood close to the equator, at roughly the same latitude as present-day southern India.

The researchers reconstructed the deep past by analyzing several kinds of data: from fossils, charcoal left by ancient wildfires, stable isotopes from organic matter, and carbonate nodules that formed in ancient soils.

Fossilized bones, pollen grains and fern spores revealed the types of animals and plants living at different times, marked by layers of sediment.

Dinosaurs remained rare among the fossils, accounting for less than 15 percent of vertebrate animal remains.

They were outnumbered in diversity, abundance and body size by reptiles known as pseudosuchian archosaurs, the lineage that gave rise to crocodiles and alligators.

The sparse dinosaurs consisted mostly of small, carnivorous theropods.

Big, long-necked dinosaurs, or sauropodomorphs–already the dominant plant-eaters at higher latitudes–did not exist at the study site nor any other low-latitude site in the Pangaea of that time, as far as the fossil record shows.

Abrupt changes in climate left a record in the abundance of different types of pollen and fern spores between sediment layers.

Fossilized organic matter from decaying plants provided another window on climate shifts. Changes in the ratio of stable isotopes of carbon in the organic matter bookmarked times when plant productivity declined during extended droughts.

Drought and fire

Wildfire temperatures varied drastically, the researchers found, consistent with a fluctuating environment in which the amount of combustible plant matter rose and fell over time.

The researchers estimated the intensity of wildfires using bits of charcoal recovered in sediment layers.

The overall picture is that of a climate punctuated by extreme shifts in precipitation and in which plant die-offs fueled hotter fires. That in turn killed more plants, damaged soils and increased erosion.

Atmospheric carbon dioxide levels, calculated from stable isotope analyses of soil carbonate and preserved organic matter, rose from about 1,200 parts per million (ppm) at the base of the section, to about 2,400 ppm near the top.

At these high CO2 concentrations, climate models predict more frequent and more extreme weather fluctuations consistent with the fossil and charcoal evidence.

Continuing shifts between extremes of dry and wet likely prevented the establishment of the dinosaur-dominated communities found in the fossil record at higher latitudes across South America, Europe, and southern Africa, where aridity and temperatures were less extreme and humidity was consistently higher.

Resource-limited conditions could not support a diverse community of fast-growing, warm-blooded, large dinosaurs, which require a productive and stable environment to thrive.

“The conditions would have been something similar to the arid western United States today, although there would have been trees and smaller plants near streams and rivers, and forests during humid times,” says Whiteside.

“The fluctuating and harsh climate with widespread wildfires meant that only small two-legged carnivorous dinosaurs could survive.”

Dinosaurs and their exaggerated structures: species recognition aids, or sexual display devices? Here.

Mastodon discovery in Michigan backyard


This video from the USA says about itself:

Bachelor party makes rare mastodon fossil discovery

13 June 2014

People at a bachelor party on a lake shore in New Mexico stumbled upon a rare fossil: the skull of a mastodon. It is considered to be an ancient elephant, complete with tusks and teeth. Scott Pelley reports.

From Popular Science in the USA today:

These Guys Found The Remains Of A 14,000-Year-Old Butchered Mastodon In Their Backyard

Mastodon burgers anyone?

By Mary Beth Griggs

Posted 39 minutes ago

It isn’t every day that you find bones in your backyard, much less a 4-foot long rib bone sticking out of the earth. After that initial, massive find, neighbors Daniel LaPoint Jr. and Eric Witzke kept digging, eventually unearthing 42 massive bones from a property in Bellevue Township, Michigan last November. At first, they thought the bones might have belonged to a dinosaur, but it turns out that the remains were far younger.

“Preliminary examination indicates that the animal may have been butchered by humans,” Daniel Fisher, director of the University of Michigan Museum of Paleontology told the Lansing State Journal. Fisher examined the bones when LaPoint and Witzke contacted the museum, and eventually determined that in addition to being butchered by humans, the bones belonged to a 37-year-old mastodon (a relative of elephants and mammoths) that lived roughly 14,000 years ago.

The Journal reports that while unusual, finding the bones of mastodons isn’t totally unheard of in Michigan; about 330 sites have been confirmed around the state, two in the past year.

Fossils found on private land in the United States belong to the landowner, not the government, so the fossil finders LaPoint and Witzke are keeping a few of the bones as the coolest mementoes ever and donating the rest to the University of Michigan Museum of Paleontology. But before they travelled to the museum, the pair took the bones to a local school, where kids got to experience the fossils up close and personal.

“All the kids got to pick them up and hold them. Some kids, it was life-changing for them. To change one kid’s life because they got to touch it, I think, is an incredible opportunity.” LaPoint told the Lansing State Journal.

See also here.

United States scientist sacked for opposition to nuclear weapons


This video from Japan about nuclear destruction is called George Takei Remembers Hiroshima.

By Tom Hall in the USA:

US researcher victimized over article opposing nuclear weapons

5 August 2014

The Los Alamos National Laboratory fired James E. Doyle, a respected nuclear security expert, in early July after more than a year of persecution stemming from a scholarly article he had published calling for nuclear disarmament, according to an account published Thursday by the Center for Public Integrity.

The fact that a US government laboratory victimized a researcher for expressing opposition to nuclear weapons, a view shared by the overwhelming majority of the world’s population, testifies to the crisis-ridden character of American foreign policy. In case after case around the world, the US is attempting to shore up its declining supremacy through increasingly reckless and brazen acts of aggression, up to and including stoking conflict with Russia and China, both nuclear powers.

Located in New Mexico, the Los Alamos National Laboratory is a Department of Energy facility that researches and develops nuclear weapons. It is one of the largest research facilities in the world and has an annual budget of over $2 billion. Doyle had worked for 17 years as a contractor in the lab’s Nuclear Nonproliferation Division.

In February 2013, Doyle published a front-page article in Survival, the journal of the UK-based think tank International Institute for Strategic Studies (IISS). Titled “Why Eliminate Nuclear Weapons?”, the piece argued that nuclear deterrence was a “myth” that damaged the ability of world governments to “meet the mutual global challenges of the twenty-first century.”

Doyle’s article dismantles the various official legends surrounding nuclear weapons. He disputes the shopworn assertion that the bombing of Hiroshima and Nagasaki by the United States in World War II saved tens of thousands of lives by precluding an invasion of the Japanese mainland, citing the “emerging view among historians that the entry of the Soviet Union into the Pacific War on 9 August 1945 was more decisive in Japan’s decision to surrender than the threat of further atomic bombings.”

Moreover, Doyle points to the various near-misses during the Cold War, as well as the recklessness of American and Soviet politicians and military leaders during the Cuban missile crisis, as contradicting the theory that nuclear deterrence “induces caution during crises, [making] leaders more risk-adverse.” From this he concludes, “It is clearly unreasonable to assert that evidence supports the claim that nuclear deterrence was the major cause of war-avoidance [in the post-war era]. This assertion is a belief, unsupported by anything approaching a strong, clear body of historically documented evidence.” He ends by appealing to the “international community” to eliminate nuclear weapons by 2045, the 100-year anniversary of the atomic bombings of Japan.

Doyle submitted his article, prepared over months in his spare time, for review by the laboratory’s censors, although he was not required to do so. While his supervisors encouraged him to adopt a more “moderate” stance to avoid hurting the interests of the laboratory, they did not raise any concerns about classified information and did not attempt to prevent him from publishing the article.

Less than a week after publication, however, Doyle’s superiors declared that the article contained classified information. As part of a phony investigation, they demanded that Doyle hand over copies of every article he had ever published.

Demonstrating the politically motivated character of the investigation, Los Alamos’ Chief Classification Officer Daniel Gerth overruled three subordinates who advised him that they had found no classified material in the article. Despite making no effort to remove the article from circulation, which is still freely available on the IISS’s website, security officials at the laboratory demanded access to Doyle’s home computer in order to delete Doyle’s personal copies of the article from his hard drive.

The Laboratory administration suspended Doyle’s security clearance for one month. In addition, they suspended, rather than revoked, Doyle’s access to information on foreign nuclear programs, a method of proceeding that prevented him from appealing their action. Such information was crucial to Doyle’s work as a nuclear nonproliferation expert. Finally, on July 8, 2014, the Laboratory fired him.

There are indications that the campaign against Doyle originated from sections of Congress. The Center for Public Integrity cites Doyle’s former supervisor, Scott Gibbs, as saying that the lab’s government relations office in Washington had told him that Doyle’s article had upset someone on the House Armed Services Committee. Gibbs refused to comment further, and Washington officials contacted by the Center for Public Integrity declined to confirm or deny Gibb’s allegations.

However, the fact that all four of the complaints lodged by Doyle with numerous government agencies were summarily dismissed despite the obviously political character of the case suggests widespread collusion to punish Doyle for his remarks.

Doyle is a solidly establishment figure. Before working 17 years at Los Alamos, he wrote the Department of Energy’s plan for securing nuclear material in Russia in the aftermath of the collapse of the Soviet Union. He is a well-known researcher in nuclear non-proliferation and wrote a textbook on the subject that is used in more than 30 universities around the world. Indeed, his article opposes nuclear proliferation from the standpoint of safeguarding American “national security” and quotes Ronald Reagan and Barack Obama.

Yet clearly he is aware of the suicidal implications of contemporary American foreign policy and brought those concerns to the public at large in his article. This was considered a red line by sections of the US security apparatus.

The article clearly touched a nerve in government circles when it declared, “Current US nuclear posture with respect to Russia seems to be completely out of step with declared policy. In 1994, Russia and the United States reached a bilateral de-targeting agreement…but if Russia is not presumed to be a potential adversary, [the] fundamental features of the current US nuclear force structure and operating posture make little sense.” Although he holds back from any conclusions, the evidence Doyle offers makes clear that the real aim of US nuclear policy is maintaining an aggressive war footing, primarily against Russia, with an eye toward asserting its dominance over every area of the globe.

The government is clearly fearful of the examples set by Edward Snowden and Chelsea Manning. Because of the immense dangers involved and the complete lack of any support for these policies among the population, the ruling elite cannot tolerate any dissension in the ranks of the military-industrial complex.

The author also recommends:

Are you ready for nuclear war?
[30 July 2014]

New Mexico dinosaurs, new study


This video is called Theropod cladogram.

From PLOS ONE:

Small Theropod Teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and Their Implications for Understanding Latest Cretaceous Dinosaur Evolution

Thomas E. Williamson, Stephen L. Brusatte

Published: April 07, 2014

Abstract

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs.

Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns.

We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian – Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas.

The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately co-eval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species.

A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern [is] seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction.

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Good American aplomado falcon news


This video from the USA says about itself:

16 March 2009

This is a video of Aplomado Falcons that have been reintroduced in south-eastern New Mexico. This is an educational video to familiarize people with the movements of the falcons and the type of preferred habitat. The recovery project is a group effort involving the US Fish and Wildlife Service, The Peregrine Fund, Turner Endangered Species Fund and other organizations.

From BirdNote in the USA:

Aplomado Falcon

Species Recovery Projects Are Working!

Aplomado Falcons were once widespread residents of the American Southwest, but by the 1950s, they’d disappeared entirely from the region. Loss of habitat, loss of prey, and pesticides all played a role.

But in the 1980s, a group called The Peregrine Fund began breeding captive Aplomado Falcons. Over the next 25 years, 1,500 fledglings were set free in South Texas. At the same time, conservation pacts with private landowners provided more than two million acres of habitat. Learn more in Related Resources below.