Navigation Links
Fossil discovery represents new milestone in early mammal evolution
Date:8/25/2011

s on the mammalian family tree than to the pouched marsupials, such as kangaroos.

"Understanding the beginning point of placentals is a crucial issue in the study of all mammalian evolution," says Luo.

Modern molecular studies, such as DNA-based methods, can calculate the timing of evolution by a "molecular clock."

But the molecular clock needs to be cross-checked and tested by the fossil record.

Prior to the discovery of Juramaia, the divergence of eutherians from metatherians posed a quandary for evolutionary biologists: DNA evidence suggested that eutherians should have shown up earlier in the fossil record--around 160 million years ago.

The oldest known eutherian was Eomaia, dated to 125 million years ago. (Eomaia was originally described in 2002 by a team of scientists led by Luo and Carnegie mammalogist John Wible.)

The discovery of Juramaia provides much earlier fossil evidence to corroborate the DNA findings, filling an important gap in the fossil record of early mammal evolution and helping to establish a new milestone of evolutionary history.

"These scientists have used the rich fossil mammal record to test evolutionary hypotheses proposed by their colleagues studying living mammals using genetic data," says Chuck Lydeard, program director in the National Science Foundation's NSF) Division of Environmental Biology, which co-funded the research with NSF's Division of Earth Sciences.

Juramaia also reveals adaptive features that may have helped the eutherian newcomers survive in a tough Jurassic environment.

Juramaia's forelimbs are adapted for climbing. Since the majority of Jurassic mammals lived exclusively on the ground, the ability to escape to the trees and explore the canopy might have allowed eutherian mammals to exploit an untapped niche.

Luo supports this perspective: "The divergence of eutherian mammals from marsupials eventually led to the place
'/>"/>

Contact: Cheryl Dybas
cdybas@nsf.gov
703-292-7734
National Science Foundation
Source:Eurekalert  

Page: 1 2 3

Related biology news :

1. Europe rallies behind nanotechnology to wean world from fossil fuels
2. Researchers uncover worlds oldest fossil impression of a flying insect
3. Caltech geobiologists discover unique magnetic death star fossil
4. Living fossil tree contains genetic imprints of rain forests under climate change
5. Bacterial biofilms as fossil makers
6. Hobbit fossils represent a new species, concludes University of Minnesota anthropologist
7. Dinosaur fossils fit perfectly into the evolutionary tree of life
8. Early whales gave birth on land, fossil find reveals
9. Worlds largest snake discovered in fossilized rainforest
10. Origin of claws seen in 390-million-year-old fossil
11. Famous fossil Lucy scanned at the University of Texas at Austin
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Fossil discovery represents new milestone in early mammal evolution
(Date:11/21/2014)... According to a new market research report ... Control, Intrusion Detection, Parking Management, Under Vehicle Inspection), End ... - Global Forecasts to 2020", published by MarketsandMarkets, The ... $25 Billion in 2014 and is expected to reach ... 8.69%. Browse 116 market data Tables and ...
(Date:11/18/2014)... Nov. 18, 2014  The Secure Identity & ... today jointly announce the formation of The Airport ... its Identity and Biometric Entry and Exit ... received official support from BORDERPOL, the international non-profit ... and provide expertise regarding border security, traveler and ...
(Date:11/12/2014)... Nov. 12, 2014 Crossmatch™, a leading provider ... U.are.U ® fingerprint readers have been deployed throughout ... Central Mexico . The bakery chain implemented ... payroll issues caused by employees clocking in for each ... fingerprint readers, Montparnasse relied on paper timecards and a ...
Breaking Biology News(10 mins):Industrial Security Systems Market Worth $38 Billion by 2020 2Industrial Security Systems Market Worth $38 Billion by 2020 3Identity Management, Document Authentication and Biometric Companies Form "The Airport Entry and Exit Working Group", Releasing the Framework to Help Guide the Department of Homeland Security and Congress Towards Solutions 2Identity Management, Document Authentication and Biometric Companies Form "The Airport Entry and Exit Working Group", Releasing the Framework to Help Guide the Department of Homeland Security and Congress Towards Solutions 3Montparnasse Pasteleria Achieves Time and Attendance Transparency with Crossmatch U.are.U Fingerprint Readers 2
... 12th International Coral Reef Symposium (ICRS 2012), the world,s ... years, will begin Monday, July 9, in Cairns, Queensland, ... policy makers, managers, and conservationists to present the latest ... the knowledge and findings presented during the symposium, daily ...
... superinfection may be as common as initial HIV infection ... a new study led by researchers at the Johns ... Institute of Allergy and Infectious Diseases (NIAID). In the ... heterosexual population, researchers examined the rate of superinfection among ...
... report that the parasitic ,Varroa, mite has caused the ... colonies. This association is now thought to contribute to ... honey bee colonies. The current monetary value of honey ... is estimated at about $15-$20 billion annually, The research ...
Cached Biology News:Coral reef experts to present latest coral reef science during July symposium 2Coral reef experts to present latest coral reef science during July symposium 3New data suggests HIV superinfection rate comparable to initial HIV infection 2New data suggests HIV superinfection rate comparable to initial HIV infection 3
(Date:12/17/2014)... N.J. (PRWEB) December 17, 2014 ... (Euronext: IPN; ADR: IPSEY), today announced ... (referred to as Somatuline®) was approved by the ... treatment of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) in adult ... advanced or metastatic disease to improve progression-free survival ...
(Date:12/17/2014)... Texas (PRWEB) December 17, 2014 ... on Global Quartz Tubing industry. For an overview ... definition, classification, application, industry chain structure, industry overview, ... quartz tubing industry has witnessed rapid ... a number of acquisitions. This report mentions quartz ...
(Date:12/17/2014)... (PRWEB) December 17, 2014 Gene ... that it has entered into a technology access ... (ADM) to apply DNA2.0’s proprietary protein engineering technology, ... process. , “We are extremely excited that the ... platform. This proprietary bioengineering technology has now ...
(Date:12/17/2014)... , Dec. 16, 2014  Vermillion, Inc. (NASDAQ: ... on gynecologic disease, today announced the next step in ... premier bio-analytics solutions provider with the naming of current ... and Chief Executive Officer, while current Chairman of the ... to serve as Chairman. These changes are effective January ...
Breaking Biology Technology:Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 2Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 3Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 4Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 5Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 6Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 7Ipsen Announces the FDA Approval of Somatuline® Depot® (lanreotide) Injection for the Treatment of Gastroenteropancreatic Neuroendocrine Tumors 82020 Quartz Tubing Market: Global Development & Forecasts Analysis Now at DeepResearchReports.com 2ADM and DNA2.0 Enter Into Protein Engineering Technology Access and Service Agreement 2Vermillion Names Valerie Palmieri CEO; James LaFrance to continue as Chairman of Board 2Vermillion Names Valerie Palmieri CEO; James LaFrance to continue as Chairman of Board 3Vermillion Names Valerie Palmieri CEO; James LaFrance to continue as Chairman of Board 4
... depletion cocktail is tailored to ... suspensions of rat spleen cells. ... StemSep (or compatible 0.5 Tesla) ... T cell content of the ...
CleanCut agarose is used to prepare genomic DNA plugs for use in pulsed field gel electrophoresis (PFGE) applications. Supplied as a 12 ml solution of 2% agarose....
... an intelligent full microplate washer with a 96 ... instrument gives you the best of two worlds ... , Performance ,Separate wash and aspiration ... A dispense precision of better than 2% CV ...
... culture scale-up, these culture chambers produce cell ... 9 range and are useful alternatives ... • High mechanical • strength and structural ... shipping • Certified nonpyrogenic and sterilized by ...
Biology Products: