Navigation Links
Fossil egg discovered in Lleida (Spain) links dinosaurs to modern birds
Date:7/12/2012

Before her death in December 2010, Nieves Lpez Martnez, palaeontologist of the Complutense University of Madrid, was working on the research of dinosaur eggs with a very peculiar characteristic: an ovoid, asymmetrical shape. Together with Enric Vicens, palaeontologist of the Universitat Autnoma de Barcelona, the two scientists conducted an exhaustive analysis of their discovery, recently published in the journal Palaeontology.

The new type of dinosaur egg has been given the scientific name of Sankofa pyrenaica. The eggs were discovered in the Montsec area of Lleida, in two sites located on either side of the Terradets pass.

The South Pyrenean area is rich in dinosaur egg sites, most of which correspond to sauropod eggs from the upper Cretaceous, dating back more than 70 million years ago. During that period, the area was a coastal area full of beaches and deltas which won land from the sea through sediment accumulation. Sand and mud from that period gave way, millions of years later, to the sandstone and marl where dinosaur remains now can be found. On the beach ridges and flat coastal lands is where a large group of dinosaurs laid their eggs.

The sites where the discoveries were made correspond to the upper Cretaceous, between the Campanian and Maastrichtian periods, some 70 to 83 million years ago. The fossils found belong to small eggs measuring some 7 centimetres tall and 4 cm wide, while the eggshell was on average 0.27mm thick. Most of the eggs found were broken in small fragments, but scientists also discovered more or less complete eggs, which can be easily studied in sections. The eggs found at the sites all belong to the same species. The main difference when compared to other eggs from the same period is their asymmetrical shape, similar to that of chicken eggs. The more complete samples clearly show an oval form rarely seen in eggs from the upper Cretaceous period and similar to modern day eggs.

Their shape is a unique characteristic of theropod eggs from the upper Cretaceous period and suggests a connection with bird eggs. Non avian dinosaur eggs are symmetrical and elongated. Asymmetry in bird eggs is associated to the physiology of birds: they take on this shape given the existence of only one oviduct which can form only one egg at a time. In this case the isthmus, the region in the oviduct creating the eggshell membrane, is what gives the egg its asymmetrical shape. Thanks to this shape, the wider end contains a bag of air which allows the bird to breathe in the last stages of its development. This evolutionary step was still relatively underdeveloped in dinosaurs.

Thus, the egg discovered by UCM and UAB researchers in certain manners represents the missing link between dinosaurs and birds. Only one other egg, discovered in Argentina and corresponding to a primitive bird from the same period, has similar characteristics. The discover represents proof in favour of the hypothesis that non avian theropods, the dinosaurs of the Cretaceous period, and birds could have had a common ancestor.


'/>"/>
Contact: Enric Vicens
Enric.vicens@uab.cat
34-935-811-783
Universitat Autonoma de Barcelona
Source:Eurekalert

Related biology news :

1. Fossil turtle from Colombia round like car tire
2. Work starts on fossil fuel free cargo ship set to transform shipping industry
3. Human-like spine morphology found in aquatic eel fossil
4. Scientists find gold-plated fossil solution
5. Ancient giant turtle fossil revealed
6. Anthropologist finds explanation for hominin brain evolution in famous fossil
7. Buy coal? New analysis shows purchasing fossil fuel deposits best way to fight climate change
8. Seismic zones, river deltas, landslides, fossil reptiles, and more new Geology science
9. Dinosaur fossil: Even specialized predators didnt turn down free meals
10. Protecting living fossil trees
11. Can you hear me now? New strategy discovered to prevent hearing loss
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/22/2016)... -- SuperCom (NASDAQ:   SPCB ... Public Safety, HealthCare, and Finance sectors announced today that Leaders in ... implement and deploy a community-based supportive services program to reduce recidivism ... further expanding its presence in the state. ... This new program, which is expected to ...
(Date:12/20/2016)... Dec, 20, 2016   Valencell , the ... and STMicroelectronics (NYSE: STM), a global semiconductor ... applications, announced today the launch of a new, ... wearables that includes ST,s compact SensorTile ... biometric sensor system. Together, SensorTile and Benchmark ...
(Date:12/16/2016)...   IdentyTechSolutions America LLC , a leading ... and a cutting-edge manufacturer of software and hardware ... seamless, integrated solutions that comprise IDT biometric readers ... provide IdentyTech,s customers with combined physical identification and ... and theft. "We are proud to ...
Breaking Biology News(10 mins):
(Date:1/21/2017)... (PRWEB) , ... January 20, 2017 , ... Nipro Corporation ... Joint Venture (JV) under which Nipro will receive exclusive marketing and sales rights for ... establish best practices for hemodialysis patients in Japan, the new Nipro - Transonic JV ...
(Date:1/21/2017)... , Jan. 20, 2017 Interpace ... a company that provides clinically useful molecular diagnostic ... has entered into a securities purchase agreement with ... 855,000 shares of common stock in a registered ... Company has agreed to sell to the same ...
(Date:1/21/2017)... Aratana Therapeutics, Inc. (NASDAQ: PETX ... development and commercialization of innovative biopharmaceutical products for companion ... North America 2016. ... on the FDA approval of three innovative therapeutics in ... (capromorelin oral solution) and NOCITA ® (bupivacaine liposome ...
(Date:1/20/2017)... ... January 20, 2017 , ... The two newest companies ... options for patients. Vironika, a spin out from The Wistar Institute, and Sanguis, launched ... space at 3624 Market Street. , Vironika is developing a treatment for a ...
Breaking Biology Technology: