Dinosaurs had teen pregnancies too

[Dann Pigdon <dannj@alphalink.com.au>]

Dinosaurs had teen pregnancies too
Jennifer Viegas, Discovery News 

Most dinosaurs were parents before they reached adulthood, according to 
recently announced research. 

The find puts dinosaurs on the list of animals that had teenage pregnancies 
that includes crocodiles, lizards and humans. 

...The discovery, announced in Austin at the US Society of Vertebrate 
Paleontology's annual meeting, also suggests why evolution favours early 
births in these groups... 

...Lee and colleague Sarah Werning extracted bone tissue from three types of 
dinosaurs: Tyrannosaurus rex, Allosaurus and Tenontosaurus... 

...Three of the examined dinosaurs had a special type of bone tissue called 
medullary tissue that was used as temporary calcium storage before eggshells 
were made... 

...Based on the growth stages of the dinosaurs, the scientists determined 
that T. rex was laying eggs by the age of 18, Allosaurus by age 10 and 
Tenontosaurus by the very young age of 8... 


More at:
http://www.abc.net.au/science/news/stories/2007/2066062.htm 

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Dann Pigdon
GIS / Archaeologist              geo cities.com/dannsdinosaurs
Melbourne, Australia             heretichides.soffiles.com
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