SCIENCE4FREAKS™. (Preteritus)

Wednesday, January 21, 2009, 8:23 pm

Unusual fossil may rule out ancient flood

* 00:01 21 January 2009 by Catherine Brahic

IT is said that in the mists of time, the islands of New Zealand were lost, Atlantis-like, beneath the ocean. But a newly discovered fossil reptile suggests this theory does not hold water.

Marc Jones of University College London, UK, and colleagues found the portions of fossilised reptile jaw on New Zealand's South Island.

The wear patterns of the teeth suggest its owner had two parallel rows of upper teeth, and a single row of lower teeth that slotted in between. The only reptile known to have this type of jaw is the endangered tuatara and its ancestors.

With its spiny crest and unique jaw, the lizard-like tuatara is remarkable even among New Zealand's extraordinary wildlife. But what is most exciting about Jones's fossil is its age: it dates to just 3 million years after a time when some researchers have suggested the land mass that forms New Zealand sank beneath the waves.

Sink or swim?

After Zealandia – New Zealand's precursor – broke off from Antarctica, it drifted northwards and shrank, due to a combination of tectonic movements and rising sea-levels. Marine sediments that now lie above sea level provide evidence of this, but just how small the land area got is open to debate.

Some have said it could have got to 15% of its current size. More recently, a group of researchers in New Zealand suggested that the absence of fossils between 25 and 22 million years ago means the islands completely disappeared, and then later re-emerged.

If this were the case, the ancestral tuatara discovered by Jones and colleagues, and all of New Zealand's biodiversity, could only have arrived after the land drowned. To do this, the ancient reptile would have had to cross vast oceans in a few million years. The team says this is an unlikely feat for an animal that is a poor swimmer and would have rapidly dehydrated in salt water.

And it's not just the tuatara fossil that suggests New Zealand did not fully drown. "There is a lot of diversity in this fossil deposit," says Jones. "There are about 24 species of birds, a lot of plants, insects, and freshwater fish. Four million years is a long time, but that still leaves a lot of explaining."

Island havens

It would be especially difficult to explain, as there is no evidence that these species lived in neighbouring Australia at the time, and many of them would have a hard time surviving lengthy sea journeys.

Instead, Jones believes Zealandia sank, but did not disappear, allowing a certain number of species to survive and then repopulate as the continental crust re-emerged.

"Even if it was reduced to 1% of current-day land area, there would still be quite a lot of land there," says Jones. "It's quite possible there could have been an archipelago of islands and these can support a huge amount of life."

One per cent of New Zealand equates to over 2500 square kilometres – more than 1000 times the surface area of Stephen's Island where more than 30,000 tuatara currently live.

Journal reference: Proceedings of the Royal Society B (DOI: 10.1098/rspb.2008.1785)

Obama Inauguration Hub

The above is video of Obama's Inauguration Speech. Specially embed for people like me, who have not watched it yet.

Obama Inauguration Speech

That's all for today's post.

Ja-na!

Bio of the Cleristo

The one who shall be made as a fellow, Cleristo, was named as Clarence Liu. He comes to being on 19th January 1993 at 1134. Studied at South View Primary and spent 6 years there. After which he moves on to Bukit Batok Secondary, where he is now currently in..
He is a self-reliant person who lives a life without spiritual suppport. He hates people who are evil, though he believes that everyone is born equally good hearted. He treats everyone before him of equal status.
He is also a person of high compassion and cares for all around him.

Favourite quote of Shakespeare would be: "The fault, dear Brutus, is not in the stars, but in us for we are underlings."

Quotes:
"Thou shall not live, shall no live."
"Stream down that river, for new wonders beyond those waters."
"With this clap, the world shall witness the beauty and wonders. With a snap, it shall change. With that many, it has already begun so."
"Ignorance is bliss, for ignorance is not to be blamed for the wretched ones actions."
"Stop hiding, start searching."
"What is Love to cause such misery to those who fail to achieve it. Love."

HISTORY.