Friday, January 28, 2011

Dinosaurs Survived 700,000 Years After Mass Extinction

Science Daily: Dinosaurs Survived Mass Extinction by 700,000 Years, Fossil Find Suggests.

ScienceDaily (Jan. 28, 2011) — University of Alberta researchers determined that a fossilized dinosaur bone found in New Mexico confounds the long established paradigm that the age of dinosaurs ended between 65.5 and 66 million years ago.

The U of A team, led by Larry Heaman from the Department of Earth and Atmospheric Sciences, determined the femur bone of a hadrosaur as being only 64.8 million years old. That means this particular plant eater was alive about 700,000 years after the mass extinction event many paleontologists believe wiped all non-avian dinosaurs off the face of earth, forever.

Heaman and colleagues used a new direct-dating method called U-Pb (uranium-lead) dating. A laser beam unseats minute particles of the fossil, which then undergo isotopic analysis. This new technique not only allows the age of fossil bone to be determined but potentially can distinguish the type of food a dinosaur eats. Living bone contains very low levels of uranium but during fossilization (typically less than 1000 years after death) bone is enriched in elements like uranium. The uranium atoms in bone decay spontaneously to lead over time and once fossilization is complete the uranium-lead clock starts ticking. The isotopic composition of lead determined in the hadrosaur's femur bone is therefore a measure of its absolute age.

Thursday, January 27, 2011

Humans Left Africa Sooner Than Tards Realized

Associated Press: Humans may have left Africa earlier than thought.

WASHINGTON – Modern humans may have left Africa thousands of years earlier than previously thought, turning right and heading across the Red Sea into Arabia rather than following the Nile to a northern exit, an international team of researchers says.

Stone tools discovered in the United Arab Emirates indicate the presence of modern humans between 100,000 and 125,000 years ago, the researchers report in Friday's edition of the journal Science.

Wednesday, January 26, 2011

T-Rex Debate Ended?

Science Daily: No Leftovers for Tyrannosaurus Rex: New Evidence That T. Rex Was Hunter, Not Scavenger.

ScienceDaily (Jan. 26, 2011) — Tyrannosaurus rex hunted like a lion, rather than regularly scavenging like a hyena, reveals new research published in the journal Proceedings of the Royal Society B.

The findings end a long-running debate about the hunting behaviour of this awesome predator.
Abderite LOL.

Sunday, January 23, 2011

Astronomy: Capture of the Moon

"The stars did not yet revolve in the heavens; the Danaides had not yet appeared, nor the race of Deucalion; the Arcadians alone existed, those of whom it is said that they lived before the Moon, eating acorns upon the mountains." -- Apollonios Rhodios, librarian, Argonautica, ~246 B.C.

"These were Arcadians of Evander's following, the so‑called Pre-Lunar people." -- Plutarch, historian, Moralia: The Roman Questions #76, 1st century

"The passages in Ovid as to the existence of the Arcadians before the Moon are universally known." -- Alexander Von Humboldt, naturalist, 1851

"...the pre-Hellenic Pelasgian inhabitants of Arcadia called themselves Proselenes, because they boasted that they came into the country before the Moon accompanied the Earth. Pre-Hellenic and pre-lunarian were synonymous." -- Alexander Von Humboldt, naturalist, 1851

"Capture of our Moon becomes the only option, it cannot have been created from the Earth." -- Wallace Thornhill, physicist, October 2000

Astronomy: Capture of the Moon, Time Magazine, May 1963

To the casual reader, the story may sound like a far-out effort at science fiction. But the moon tale told by Swedish Physicist Hannes Alfven amounts to much more than an imaginative voyage into the distant past; it is an ingenious effort to reconstruct a cosmic catastrophe that changed the composition of man's earth and set a new course for the moon more than 2 billion years ago.

Dr. Alfven's theory reaches back to a time when the moon was not yet a satellite of earth, when it soared around the sun like any other planet on its own independent orbit. Trouble was, its orbit took the moon near its large neighbor, the earth. In Icarus, International Journal of the Solar System, Alfven suggests that eventually the moon ventured too close and was captured by the earth's gravity.

Strange Discrepancy. That far, the theory is disarmingly simple. But astronomers can calculate the new orbit of such a recent captive, and the moon does not move along the expected path. Instead of curving along an eccentric ellipse far out into space and then close to earth again, the moon moves along a mildly deformed circle. Such a course would be explainable for a satellite that was moving in the opposite direction from the earth's rotation at the time it was captured. But the moon now revolves in the same direction, and to prove his theory correct. Dr. Alfven somehow had to account for the change.

When the moon was first captured. Dr. Alfven believes, it did indeed curve through space in the opposite direction from the earth's rotation. And, as expected of such a satellite, it drew gradually closer to the earth. Its orbit became circular. About 2.5 billion years ago, the earth-moon system passed through a violent crisis. The approaching moon exerted more and more gravitational pull on the earth's oceans. Tides miles high swept around the globe in a few hours. At last the moon reached Roche's limit,* the closest that a satellite can come to its parent body without being torn to bits by gravitational forces. When the moon passed this boundary, fragments of all sizes began flying off it. Some fell on the earth, heating its atmosphere, churning its surface, forming a halo of dust around it. Any life that existed on earth at the time was probably exterminated. So much moon matter fell on the earth that its high-speed impact changed the earth's rotation.

Buoyant Granite. When the giant meteors stopped falling, and the atmosphere cooled off, the diminished moon, having lost about half its mass, was once more just outside Roche's limit. It was now revolving in the same direction as the earth, and as a result it withdrew slowly to its present distance (240,000 miles).

To support this fast-spinning theory, Alfven points out that the earth's continents are made of comparatively light granitic rock that floats on the heavy basalt underlying the oceans. The basalt, he says, may be the original earth. But the buoyant granite of the continents has about the same density as the moon and nearly equals the moon's present mass. He suspects that it is moon-stuff that dived to earth through the fiery atmosphere 2.5 billion years ago.

* Discovered by French Mathematician Edouard Roche in 1850. For the present earth-moon system. Roche's limit is about 9,700 miles from the earth's center. The limit applies to bodies held together principally by gravitation, not to man-made satellites.

Thursday, January 20, 2011

Female Pterosaurs Were Crestless

Science Daily: How to Tell a Pterodactyl's Sex: Dino-Era Riddle Solved by New Fossil Find.

The discovery of a flying reptile fossilised together with an egg in Jurassic rocks (about 160 million years old) in China provides the first direct evidence for gender in these extinct fliers. This fossil shows that females were crestless, solving the long-standing problem of what some pterosaurs did with their spectacular head crests: showy displays by males.

The find was made by an international team of researchers from the Universities of Leicester, Lincoln and the Geological Institute, Beijing. Details of the unique new find are published in the journal Science.

David Unwin, a palaeobiologist in the Department of Museum Studies at the University of Leicester, was part of the research team that studied the fossil. He said:

"Pterosaurs, flying reptiles, also known as pterodactyls, dominated the skies in the Mesozoic Era, the age of dinosaurs, 220-65 million years ago. Many pterosaurs have head crests. In the most spectacular cases these can reach five times the height of the skull. Scientists have long suspected that these crests were used for some kind of display or signalling and may have been confined to males, while females were crestless. But, in the absence of any direct evidence for gender this idea remained speculative and crested and crestless forms were often separated into completely different species."

Monday, January 17, 2011

Caligula's Tomb Rediscovered

Guardian: Caligula's tomb found after police arrest man trying to smuggle statue.

The lost tomb of Caligula has been found, according to Italian police, after the arrest of a man trying to smuggle abroad a statue of the notorious Roman emperor recovered from the site.

After reportedly sleeping with his sisters, killing for pleasure and seeking to appoint his horse a consul during his rule from AD37 to 41, Caligula was described by contemporaries as insane.

With many of Caligula's monuments destroyed after he was killed by his Praetorian guard at 28, archaeologists are eager to excavate for his remains.

Friday, January 7, 2011

The Not-So Naked Ape

Science Daily: Lice DNA Study Shows Humans First Wore Clothes 170,000 Years Ago.

ScienceDaily (Jan. 7, 2011) — A new University of Florida study following the evolution of lice shows modern humans started wearing clothes about 170,000 years ago. ...

The data shows modern humans started wearing clothes about 70,000 years before migrating into colder climates and higher latitudes, which began about 100,000 years ago. This date would be virtually impossible to determine using archaeological data because early clothing would not survive in archaeological sites.
Hmmm...the data shows that even Neanderthals wore clothes prior to 168,000 B.C. I guess modern humans devolved to be too stupid to figure that out.