Tuesday, June 5, 2007

Last Survivor Of The Dinosaur Age May Become Extinct Due To Global Warming.

It has survived ice ages, volcanic eruptions and the intrusion of humans on its South Pacific island home, but New Zealand's last survivor of the dinosaur age may become extinct due to global warming.


Mounted with spiny scales from head to tail and covered by rough, grey skin that disguises them among the trees, the tuatara is one of the world's oldest living creatures.

But the lizard-like reptile is facing increasing risk of extinction from global warming because of its dependency on the surrounding temperature which determines the sexes of unborn young while still in their eggs.
"They've certainly survived the climate changes in the past but most of them (past climate changes) have been at a more slower rate," said Jennifer Moore, a Victoria University researcher investigating the tuatara's sexual behaviour.
More at:http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=459702&in_page_id=1965&ito=1490

"So you wouldn't expect these guys to be able to adapt to a climate that's changing so rapidly."

The sex of a tuatara depends on the temperature of the soil where the eggs are laid. A cooler temperature produces females, while a warmer soil temperature results in male offsprings.

So named by New Zealand's indigenous Maori people because of the spines on its back, the tuatara is the only survivor of its species of reptile that flourished during the age of the dinosaurs, some 200 million years ago.

It can grow up to 50 centimetres (20 inches) and weigh up to one kilogram (2.2 pounds) and like its reptile relative, the turtle, the slow-moving tuatara can live more than 100 years, feeding mainly on insects.

But scientists say its long life span as well as its four-year breeding cycle - relatively slow for a reptile - will make the adaptation process more difficult.

According to Moore, a temperature above 21.5 degrees Celsius (71 degrees Fahrenheit) creates more male tuatara while a cooler climate leads to females.

Already male tuatara on a tiny predator-free island near the top of New Zealand's South Island outnumber females by 1.7 times, Moore explained.

Unique wildlife


Thanks to its geographic isolation, New Zealand is home to a host of unique wildlife, such as the flightless kiwi bird.
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---------------oOo--------------- Who Is The Father Of Zodiac?

Using modern techniques — and some rocks — a US astronomer has traced the origin of a set of ancient clay tablets to a precise date and place. The tablets show constellations thought to be precursors of the present-day zodiac.

The tablets, known collectively as MUL.APIN, contain nearly 200 astronomical observations, including measurements related to several constellations. They are written in cuneiform, a Middle-Eastern script that is one of the oldest known forms of writing, and were made in Babylon around 687 BC.

But most archaeologists believe that the tablets are transcriptions of much earlier observations made by Assyrian astronomers. Just how much older has been disputed — the estimates go back to 2,300 BC.

Now Brad Schaefer, an astronomer at Louisiana State University in Baton Rouge, says he has dated the observations to 1,370 BC, give or take a century.

The tablets contain a number of different observations, including the day each year that certain constellations first appeared in the dawn sky. These dates change over the millennia because of a tiny wobble in the Earth's axis.

"It's like a big hour hand in the sky," Schaefer says.

By studying these dates and other astronomical information, such as the dates certain constellations were directly overhead, Schaefer nailed down the year the measurements were taken.

He also worked out that the ancient observers lived within roughly 100 kilometres of 35.1° N — an area that includes the ancient Assyrian cities of Ninova and Asur. The results were presented at the American Astronomical Society's summer meeting in Honolulu, Hawaii.

Star gazing

To double-check his measurements, Schaefer did his own observations at the McDonald Observatory in the Davis Mountains of Texas. Rather than using the observatory's massive 9.2-metre telescope, he stood outside and gazed at the stars. "The best equipment I used was rocks to mark where my feet were," he says.

Nevertheless, these measurements allowed him to pinpoint his own position and date more precisely than he could those of the Assyrian astronomers. He is not sure why his measurements worked better.


Schaefer's work will help settle a long-standing debate, says Hermann Hunger, an Assyriologist at the University of Vienna in Austria. Previously, historians had based their arguments on single stars or constellations on the tablets.

Schaefer's statistical analysis of all the observations on the tablets "will impress historians who cannot do the same on their own — including myself", Hunger says. He adds that most historians have settled on a rough date of 1,000 BC for the tablets, which agrees well with Schaefer's analysis.

More at:http://www.nature.com/news/2007/070528/full/070528-11.html

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---------------oOo--------------- Weird Justice

Texas judge Keith Dean, recently defeated for re- election, decided as he was cleaning out his desk in December that he would order the release of a man that he controversially sentenced to life in prison in 1990. Tyrone Brown was 17 when he committed a $2 robbery, and Dean put him on probation but changed it to life in prison when Brown shortly afterward tested positive for marijuana. (The Dallas Morning News in a series of 2006 articles had reported that Dean had failed to additionally punish a murderer who had tested positive for cocaine several times after his release on probation.)


Creme de la Weird

Clarence Horner’s hobby, apparently, was collecting tombstones, in that upon his death in 2006 in Lincoln, Neb., authorities found 47 of them in his rented storage locker

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---------------oOo--------------- Mysterious Radio Waves

The Huygens Atmosphere Structure Instrument (HASI) scored a first in 2005 by measuring the electrical conductivity of Titan’s atmosphere. The results hint at a new way to investigate the subsurface layers of Titan and could provide insight into whether or not Titan has a subsurface ocean.

The Permittivity, Waves and Altimetry (PWA) sensor on Huygens detected an extremely low frequency (ELF) radio wave during the descent. It was oscillating very slowly for a radio wave, just 36 times a second, and increased slightly in frequency as the probe reached lower altitudes.
If the PWA team confirms that the signal is a natural phenomenon and not an artefact of the way the instrument worked, they will have discovered a powerful new way to probe not just the atmosphere of Titan but its subsurface as well.

The only other world on which ELF waves were detected before was Earth. They are reflected by both the surface of the Earth and its ionosphere, the rarefied region of the atmosphere where most particles are electrically charged. This turns the atmosphere into a giant ‘sound box’ where certain frequencies of ELF waves resonate and are reinforced, whilst other die away.

On Titan, however, the surface is a poor reflector because of its low conductivity and so these waves penetrate the interior. “The wave could have been reflected by the liquid-ice boundary of a subsurface ocean of water and ammonia predicted by theoretical models,” says Fernando Simões, CETP/IPSL-CNRS, France, and a member of the PWA team.
More at:http://www.scientificblogging.com/news/mysterious_radio_waves_on_titan

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