Fossil of most primitive 4-legged creature found

[actsnoblemartin]

http://news.yahoo.com/s/ap/20080625/...fish_evolution

WASHINGTON - Scientists unearthed a skull of the most primitive four-legged creature in Earth's history, which should help them better understand the evolution of fish to advanced animals that walk on land.

The 365 million-year-old fossil skull, shoulders and part of the pelvis of the water-dweller, Ventastega curonica, were found in Latvia, researchers report in a study published in Thursday's issue of the journal Nature. Even though Ventastega is likely an evolutionary dead-end, the finding sheds new details on the evolutionary transition from fish to tetrapods. Tetrapods are animals with four limbs and include such descendants as amphibians, birds and mammals.

[crin63]

The 365 million-year-old fossil skull, shoulders and part of the pelvis of the water-dweller

I find it interesting that they just throw out the number 365 million-year-old. How do they know? They just found it. They weren't there when it died. What proof do they have that its that old?

[Hagbard Celine]

I find it interesting that they just throw out the number 365 million-year-old. How do they know? They just found it. They weren't there when it died. What proof do they have that its that old?

They measure the rate of radioactive decay. The measure is very approximate. The rate of error can even be as large as a million years.

[hjmick]

I find it interesting that they just throw out the number 365 million-year-old. How do they know? They just found it. They weren't there when it died. What proof do they have that its that old?

They didn't just find it, they just published their findings. It was probably found months ago and now that their research is done they have published their findings.

As to how they determine the age, it's called Radiocarbon Dating, see Hag's post.

[Yurt]

They measure the rate of radioactive decay. The measure is very approximate. The rate of error can even be as large as a million years.

actually not true, i studied this and wrote papers on it in college, if in fact a world wide flood occurred, the radioactive, including atmospheric measurements would be vastly different given the world went through such a dramatic climate shift and was under water for 40 days...further, they are simply guessing at the initial rate of radioactive isotopes based on current data, not thousand year old and not pre-flood data

woomp, there is

[Gaffer]

actually not true, i studied this and wrote papers on it in college, if in fact a world wide flood occurred, the radioactive, including atmospheric measurements would be vastly different given the world went through such a dramatic climate shift and was under water for 40 days...further, they are simply guessing at the initial rate of radioactive isotopes based on current data, not thousand year old and not pre-flood data

woomp, there is

Gotta disagree with you. There was no world wide flood.

[manu1959]

actually not true, i studied this and wrote papers on it in college, if in fact a world wide flood occurred, the radioactive, including atmospheric measurements would be vastly different given the world went through such a dramatic climate shift and was under water for 40 days...further, they are simply guessing at the initial rate of radioactive isotopes based on current data, not thousand year old and not pre-flood data

woomp, there is

proof of a world wide flood.....

[bullypulpit]

They measure the rate of radioactive decay. The measure is very approximate. The rate of error can even be as large as a million years.

Also by the geologic strata the fossil was found in.

[Nukeman]

actually not true, i studied this and wrote papers on it in college, if in fact a world wide flood occurred, the radioactive, including atmospheric measurements would be vastly different given the world went through such a dramatic climate shift and was under water for 40 days...further, they are simply guessing at the initial rate of radioactive isotopes based on current data, not thousand year old and not pre-flood data

woomp, there is

gotta disagree with the radioactive decay rate. Regardless if you have 1 million Bq or you have 1 Bq the decay is EXACTLY the same for the isotope. the one constant you can be sure of is radioactive decay, it never changes.....