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Larry Heaman with the dinosaur fossil found in New Mexico  (Source: University of Alberta)
New dinosaur bone found in New Mexico suggests the hadrosaur lived beyond mass extinction

A fossilized dinosaur bone discovered in New Mexico contradicts previous scientific data that suggests that dinosaur extinction occurred between 65.5 and 66 million years ago, says a team of researchers from the University of Alberta

Larry Heaman, study leader from the Department of Earth and Atmospheric Sciences at the University of Alberta, along with a team of researchers from the university, have found a fossilized femur bone of a hadrosaur in New Mexico that is only 64.8 million years old, showing that dinosaurs lived 700,000 years beyond mass extinction in the late Cretaceous period. 

Paleontologists believe that dinosaurs became extinct between 65.5 and 66 million years ago when debris from a large meteorite impact blocked the sun, changing the climate drastically and killing vegetation. Paleontologists determined this time period as the age of extinction by using a traditional technique called relative chronology, which has been used in this field of science to estimate the age of fossils. Relative chronology is when a fossil's age is determined by the depositional age of a layer of sediment where the fossil was found, or by the depositional age of layers of sediment above and below the fossil. But the problem with this method is that environmental and geologic forces can cause fossils to shift or migrate from their original layers of sediment, leading to a potentially inaccurate estimate of age. 

For this particular study, Heaman and the University of Alberta team checked the age of the recently discovered dinosaur bone using a technique called U-Pb (uranium-lead) dating. This method uses a laser beam to "unseat" tiny particles of the fossil. These particles are then subjected to isotopic analysis, which both determines age and the type of food the dinosaur ate.  

The U-Pb dating method is accurate because living bone carries low levels of uranium, but fossilized bone is rich with uranium. These uranium atoms decay into lead over time, and determining the isotopic composition of the lead in fossilized bones leads to its absolute age.  

After using this technique on the femur bone of the hadrosaur, Heaman and his team concluded that the bone is 64.8 million years old, which means that this hadrosaur came from a line of dinosaurs that survived the great mass extinction in the late Cretaceous period, and lived 700,000 years beyond it. Researchers believe these particular plant-eaters were able to survive mass extinction because some of the vegetation may have survived the climate change allowing them to eat.  

Now the researchers are looking to figure out if dinosaur eggs could have potentially survived during the period of mass extinction, which would further explain the survival of these dinosaurs. They also plan to use the U-Pb dating method to continue measuring the absolute age of other dinosaur fossils. Heaman believes that this technique will replace relative chronology, and will be used to rewrite the history of the extinction of the dinosaurs.   

This study, titled "Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico," was published in Geology.

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Real Reason Dinosaurs Became Extinct
By cscpianoman on 1/31/2011 11:38:34 AM , Rating: 2
There was a massive influx of guinea pigs and hamsters, which the dinosaurs were naturally allergic too. All the dinosaurs ultimately became asthmatic and since there were no histamine blockers, albuteral inhalers and what not they all perished from the impending flood of mammal dander...

and aliens! Can't forget them too:)

By BadAcid on 1/31/2011 11:44:41 AM , Rating: 2
The aliens caught a flu and died, it was just the rodents.

By quiksilvr on 1/31/2011 11:45:15 AM , Rating: 2
By Egglick on 1/31/2011 7:15:11 PM , Rating: 2
I don't see how this is news. Obviously crocodiles, turtles, and all other modern reptiles survived, so there's no logical reason that a few other species of dinosaur couldn't as well.

I've heard some strong theories proposed that disease (spread by mosquitoes and other insects) could have done the trick. As with any major catastrophe, it was likely a combination of factors.

RE: So?
By Ammohunt on 2/1/2011 4:04:38 PM , Rating: 2
I agree 700K years is more than enough time to evolve into something better. Just shows how little we know about life and extinction cycles on our planet.

Screw up?
By torpor on 1/31/2011 12:03:59 PM , Rating: 1
This seems like the kind of error you get when someone just messes up.

It could very well be that this points to one or the other of the aging mechanisms being wrong. (this is in NO WAY to indicate support for some crackpot "young earth" theory)

I'd like to see this team use their methodology to test the age of fossils we otherwise have a date for. This "finding" screams for a measure against a control set.

RE: Screw up?
By Iaiken on 1/31/2011 1:45:25 PM , Rating: 2
This method of dating only works in areas where the fossil (or the rock immediately surrounding the fossil) contained trace Uranium in the first place. If not, you're SOL and you'll have to rely on dating based on the location in the stratum.

Where is the debate?
By ShaolinSoccer on 2/1/2011 12:08:59 AM , Rating: 2
How can a large herbivore dinosaur survive 700k (plus or minus) years after an event that wiped out the rest of the dinosaurs? (except for the small ones still around today... birds, alligators etc etc...) Did New Mexico somehow avoid the catastrophe for that long? And if it did, how about other parts of the world? 700k years is a VERY long time for something that big to survive!

Comedian wannabes, please don't reply...

margin of error
By kattanna on 2/1/2011 11:13:17 AM , Rating: 2
from the study itself

The second dinosaur bone sample from Paleocene strata just above the Cretaceous-Paleogene interface yielded a Paleocene U-Pb date of 64.8 ± 0.9 Ma

so they came to the date of 64.8 mya with a margin of error of .9 mya, so its entirely possible there is no issue here at all, as the range of difference is within the margin of error of the dating process itself.

so, until they can further refine and add more test subjects, this is much ado about nothing.

2% difference in age, from one fossil
By mattclary on 1/31/11, Rating: -1
RE: 2% difference in age, from one fossil
By Shadowmaster625 on 1/31/2011 11:36:19 AM , Rating: 5
There have been all sorts of fossils found after "zero year". But the truly compelling evidence is the fact that the fossil record indicates that the population was dying off well before "zero year". It's funny you use the phrase "earth shattering" because that is essentially exactly what happened to the dinosaurs. The earth cracked open, oceans filled in the cracks, and their migratory patterns were cut off. The event that occured 65 million years ago certainly did not help them, but they were doomed before that time.

RE: 2% difference in age, from one fossil
By gamerk2 on 1/31/2011 11:54:27 AM , Rating: 2
I think its clear the Dinosaurs were on the way out, as it were, before the Extinction event; I think its also clear [and obvious] that at least some sub-species would have survived for some time afterward, slowly dwindling down, until either they evolve, or the line dies off entirely.

And yeah, 2% varience isn't much to write home about...

By Iaiken on 1/31/2011 1:40:50 PM , Rating: 3
And yeah, 2% varience isn't much to write home about...

Depends on the person reading I guess.

When you consider that they survived 700,000 years in the face of extremely adversary conditions it is merely interesting. Compare that to our measly 195,000 years (so far) of fruitful conditions and it becomes something rather noteworthy. It may even hint at further catastrophe or steepening difficulties that they just couldn't keep up with.

RE: 2% difference in age, from one fossil
By Wy White Wolf on 1/31/2011 2:35:02 PM , Rating: 2
date of 64.8 ± 0.9 Ma

Ma ~ 1 million years

That would give it an age range of 63.9 to 65.7 million years old.

Seems to hit within the 65.5 to 66.0 range most say the mass extinction event happened.

By Shadowself on 1/31/2011 6:39:18 PM , Rating: 2
Stop talking sense.

People must not admit to error bars in their data and calculations! Numbers are absolute! /sarcasm

RE: 2% difference in age, from one fossil
By mattclary on 2/1/2011 2:37:01 PM , Rating: 2
Can't believe you were rated a 5 for a link about how the Earth is growing. lol

By FaceMaster on 2/2/2011 9:56:02 AM , Rating: 2
I think he's onto something here! The whole Universe is expanding, and yet it's not exactly 'moving apart' (ie, fire a laser a mile in one direction, then in the other and it takes the same amount of time to reach its destination). The entire universe is slowly being stretched out, much like the Earth is in that video!


By smackababy on 1/31/2011 11:36:55 AM , Rating: 1
It is clear proof the Devil is trolling scientists... Why else would he plant bones in the ground to encourage nonbelievers?

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