Navigation Links
Ancient mother spawns new insight on reptile reproduction
Date:8/27/2008

A 75-million-year-old fossil of a pregnant turtle and a nest of fossilized eggs that were discovered in the badlands of southeastern Alberta by scientists and staff from the University of Calgary and the Royal Tyrrell Museum of Palaeontology are yielding new ideas on the evolution of egg-laying and reproduction in turtles and tortoises.

It is the first time the fossil of a pregnant turtle has been found and the description of this discovery was published today in the British journal Biology Letters.

The mother carrying the eggs was found in 1999 by Tyrrell staff while the nest of eggs was discovered in 2005 by U of C scientist Darla Zelenitsky, the lead author of the article and an expert on fossil nest sites, and her field assistant. Both were found about 85 km south of Medicine Hat in the Manyberries area.

"Although it is relatively rare to find the eggs and babies of extinct animals, it is even rarer to find them inside the body of the mother," says Darla Zelenitsky, who was also involved in the first discovery of a dinosaur with eggs inside its body.

It was almost by accident that scientists realized that the fossil turtle was pregnant.

"The turtle specimen was partly broken when it was first discovered. It is this fortuitous break that revealed that the fossil was a mother," says Franois Therrien, a co-investigator of the study and curator of dinosaur palaeoecology at the Royal Tyrrell Museum.

The remains of at least five crushed eggs were visible within the body of the fossil female and a CT scan exposed more eggs hidden under its shell. The turtle, estimated to be about 40 cm long, could have produced around 20 eggs. The nest, which was laid by a different female, contained 26 eggs, each approximately 4 cm in diameter.

Both specimens belong to an extinct turtle called Adocus, a large river turtle that lived with the dinosaurs and resembles today's slider and cooter turtles.

The eggs of Adocus are extremely thick and hard, whereas those of most modern turtles are either thinner or soft-shelled. The thick eggshell may have evolved to protect the eggs from desiccation in dry environments or to protect them from voracious predators during the time of the dinosaurs.

Zelenitsky says the pregnant turtle specimen and the nest shed light on the evolution of reproductive traits of modern turtles, specifically those traits related to their eggs and nests.

"Based on these fossils, we have determined that the ancestor of living hidden-necked turtles, which are most of today's turtles and tortoises, laid a large number of eggs and had hard, rigid shells," says Therrien.


'/>"/>

Contact: Leanne Yohemas
leanne.yohemas@ucalgary.ca
403-220-5144
University of Calgary
Source:Eurekalert

Related biology news :

1. Scientists retrace evolution with first atomic structure of an ancient protein
2. CU-Boulder team discovers first ancient manioc fields in Americas
3. Ancient organisms discovered in Canadian gold mine
4. Amber specimen captures ancient chemical battle
5. Ancient whale fall from Californias Año Nuevo Island one of youngest, most complete known
6. Ancient whale fall from Californias Ao Nuevo Island one of youngest, most complete known
7. 454 Sequencing: Science paper describes a novel, highly efficient method of sequencing ancient DNA
8. Newfound ancient African megadroughts may have driven the evolution of humans and fishes
9. Ancient amphibians left full-body imprints
10. Scientists melt million-year-old ice in search of ancient microbes
11. Ancient fish bones reveal impacts of global warming beneath the sea
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/29/2017)... , March 29, 2017  higi, the health IT ... North America , today announced a ... the acquisition of EveryMove. The new investment and acquisition ... of tools to transform population health activities through the ... data. higi collects and secures data today ...
(Date:3/24/2017)... -- Research and Markets has announced the addition of ... - Industry Forecast to 2025" report to their offering. ... The Global Biometric Vehicle ... around 15.1% over the next decade to reach approximately $1,580 million ... estimates and forecasts for all the given segments on global as ...
(Date:3/22/2017)... Optimove , provider of the ... as 1-800-Flowers and AdoreMe, today announced two new ... Using Optimove,s machine learning algorithms, these features allow ... recommendations to their customers based not just on ... intent drawn from a complex web of data ...
Breaking Biology News(10 mins):
(Date:6/20/2017)... ... 20, 2017 , ... HorizonScan is providing food and ingredient ... likely threat to their products at the annual IFT conference in Las Vegas, ... expo attracts over 20,000 attendees representing food science professionals from over 90 countries ...
(Date:6/20/2017)... ... June 20, 2017 , ... ... antibody therapeutics from millions-diverse immune repertoires, announces launch of its new Surge(TM) ... Dave Johnson, PhD, CEO of GigaGen, will present on Surge at the conference. ...
(Date:6/19/2017)... ... June 19, 2017 , ... A colony of healthy ... cells and tissues by delivering pollen and nectar containing nutrients necessary for growth and ... stay healthy. , Many recent indicators point to a decline in honey bee health. ...
(Date:6/15/2017)... (PRWEB) , ... June 15, 2017 , ... ... synthetic auxin herbicides give farmers new options for managing Palmer amaranth and other ... America (WSSA) say special precautions are necessary. Auxin herbicides are known to drift ...
Breaking Biology Technology: