Navigation Links
Did humans cause ecosystem collapse in ancient Australia?

the most abundant variety is in the lightest, 12C. About 1% is 13C, a heavier sibling with an additional neutron. There is even less 14C, the unstable, radioactive heavyweight of them all.

"13C is the key," Fogel explained. "There are two main ways plants metabolize 13C . About 85% of plants belong to what is known as C3 photosynthesis group. This group incorporates less 13C than plants belonging to the second most common class, C4. Thus, the differences in 13C that we detected in the eggshells and teeth pointed to the type of plants that were consumed. Although, both types of plants were present before the extinctions, we saw a quick shift in dominance from C4 drought-resistant trees, shrubs and grasses, to C3 desert plants. "

Why did the scientists point to humans as the instigators of the ecological changes? First, they ruled out the other usual suspect--global climate change. They looked at their data in 15,000-year intervals back to 140,000 years ago. The period included dramatic climate changes, but no changes in the diet and environment until an abrupt transition was noted that corresponded to the arrival of humans. "Humans are the major suspect," commented Fogel. "However, we don't think that over-hunting or new diseases are to blame for the extinctions, because our research sees the ecological transition at the base of the food chain. Bands of people set large-scale fires for a variety of reasons, including hunting, clearing, and signaling other bands. Based on the evidence, human-induced change in the vegetation is the best fit to explain what happened at that critical juncture."


'"/>

Source:Carnegie Institution


Page: 1 2

Related biology news :

1. Yale researchers identify molecule for detecting parasitic infection in humans
2. Friendly bacteria in humans may protect against HIV
3. The lopsided brain: Attention bias is shared by humans and birds
4. Oldest cranial, dental and postcranial fossils of early modern European humans confirmed
5. Retrovirus struck ancestors of chimpanzees and gorillas millions of years ago, but did not affect ancestral humans
6. UI researcher studies deafness in fruit flies, humans
7. Chickadees can help humans get their bearings
8. Study shows humans have ability to track odors, much like bloodhounds
9. Caloric restriction wont dramatically extend life span in humans: UCLA research
10. Study identifies gene in mice that may control risk-taking behavior in humans
11. Primate virus jumps species barrier to humans for first time in Asia
Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Did humans cause ecosystem collapse ancient Australia

(Date:3/2/2015)... Calif. , March 2, 2015 ... leading developer of human interface solutions, today announced ... that is designed to enable rapid and secure ... ID™ module for gaming is a turnkey solution ... the ability to quickly integrate fingerprint ID solutions ...
(Date:3/2/2015)... 2015  Businesses have a new option for ... Rankins Enterprises has announced the launch of a ... for businesses to protect their customers, personal data, ... Beconux is a biometric transaction processing system ... to an ATM machine, the new system fuses ...
(Date:3/2/2015)...   Neurotechnology , a provider of high-precision biometric, ... Software Development Kit (SDK). The SentiGaze algorithm enables ... webcams to track eye movements and generate heatmaps based ... can be used for applications such as analysis of ... SDK can also be used to develop interfaces for ...
Breaking Biology News(10 mins):Synaptics Unveils New Fingerprint ID Solution for Gamers 2Synaptics Unveils New Fingerprint ID Solution for Gamers 3Personal Data Protection Company Launches New Product 2Neurotechnology Releases SentiGaze SDK for Eye Movement Tracking Using Ordinary Webcams 2Neurotechnology Releases SentiGaze SDK for Eye Movement Tracking Using Ordinary Webcams 3
... clean, local-source energy. Faster, more reliable technologies and ... Medical care tailored to your DNA, or neural ... and injuries. Five University of Pittsburgh faculty ... and technology as part of Faculty Early Career ...
... technology, researchers led by a Weill Cornell Medical College scientist ... about half of all prostate cancers. Estrogen-linked signaling helps ... by a chromosomal translocation, which in turn results in the ... cancers harbor a common recurrent gene fusion, and we believe ...
... life to thrive: temperature, or sunlight? The answer ... online this week in PNAS Early Edition, the explosion ... do with warmth than with light. The diversity ... strongly related to temperature, said University of Southern California ...
Cached Biology News:Pitt faculty receive awards to explore next-generation technologies 2Pitt faculty receive awards to explore next-generation technologies 3Pitt faculty receive awards to explore next-generation technologies 4Estrogen helps drive distinct, aggressive form of prostate cancer 2Estrogen helps drive distinct, aggressive form of prostate cancer 3What makes life go at the tropics? 2
(Date:3/3/2015)... (PRWEB) March 03, 2015 GlobalStemCellsGroup.com ... growing faculty. Camacho Alcocer, a biomedical researcher and founding ... will join GSCG’s team of biomedical professors who will ... program. , Criogenix SA de CV is a private ... Technological Institutions and Companies in Mexico (RENIECYT). , Camacho ...
(Date:3/3/2015)... -- Phillip Sharp, Institute Professor at the Massachusetts Institute of Technology ... the Koch Institute for Integrative Cancer Research, will receive the ... May 14, at the Chemical Heritage Foundation. Sharp is ... it was first awarded to Ralph Landau ... gave the scientific world a new view of the ...
(Date:3/2/2015)... 02, 2015 The American Society ... announced today the launch of Genetically Speaking , ... professionals on the application of human genetics in disease ... peer-to-peer interviews conducted during the ASHG 2014 Annual Meeting ... Genomics and Health Outcomes Research: What's Ready for Primetime? ...
(Date:3/2/2015)... Md. (PRWEB) March 02, 2015 Shimadzu ... sessions and present on LCMS and marijuana analysis at ... place March 8 to 12 at the Ernest N. ... Attendees can stop by booth 3121 to discuss laboratory ... the company’s innovative, proven products help save time, money ...
Breaking Biology Technology:Mario Camacho Alcocer Joins Global Stem Cells Group Faculty 2Mario Camacho Alcocer Joins Global Stem Cells Group Faculty 3Phillip Sharp to Receive 2015 Othmer Gold Medal 2Phillip Sharp to Receive 2015 Othmer Gold Medal 3American Society of Human Genetics (ASHG) and ReachMD Launch Series on Genetics and Genomics 2American Society of Human Genetics (ASHG) and ReachMD Launch Series on Genetics and Genomics 3Shimadzu Scientific Instruments Announces Product Launches, Presentations and Poster Sessions for Pittcon 2015 2Shimadzu Scientific Instruments Announces Product Launches, Presentations and Poster Sessions for Pittcon 2015 3
... Marinus Pharmaceuticals, a,developer of specialty therapeutics to treat ... Krayacich as president,and chief executive officer. Mr. Krayacich ... business development for ganaxolone, an adult and,pediatric epilepsy ... candidate., Mr. Krayacich brings more than 20 ...
... (Amex: NBS ),announced today that the new Southern Florida ... Miami, is targeted to open in,September. The center is being ... of this center, NeoStem has secured a key geographic,stronghold in ... as well as a,growing sophisticated South American presence., Chester ...
... Company hits key insulin and Apo AI(Milano), ... 5 /PRNewswire-FirstCall/ - SemBioSys Genetics Inc.,(TSX:SBS), a biotechnology ... and cardiovascular diseases, today announced its,2008 second quarter ... Insulin Program, - Submitted an ...
Cached Biology Technology:Marinus Pharmaceuticals Appoints John Krayacich as President and Chief Executive Officer 2Marinus Pharmaceuticals Appoints John Krayacich as President and Chief Executive Officer 3Marinus Pharmaceuticals Appoints John Krayacich as President and Chief Executive Officer 4NeoStem Forges Ahead in Its Plan to Open Adult Stem Cell Collection Centers in Key Locations that Can Serve as Hubs to Service Clients Nationwide 2NeoStem Forges Ahead in Its Plan to Open Adult Stem Cell Collection Centers in Key Locations that Can Serve as Hubs to Service Clients Nationwide 3SemBioSys announces second quarter 2008 financial and operational results 2SemBioSys announces second quarter 2008 financial and operational results 3SemBioSys announces second quarter 2008 financial and operational results 4SemBioSys announces second quarter 2008 financial and operational results 5SemBioSys announces second quarter 2008 financial and operational results 6SemBioSys announces second quarter 2008 financial and operational results 7SemBioSys announces second quarter 2008 financial and operational results 8SemBioSys announces second quarter 2008 financial and operational results 9SemBioSys announces second quarter 2008 financial and operational results 10SemBioSys announces second quarter 2008 financial and operational results 11SemBioSys announces second quarter 2008 financial and operational results 12SemBioSys announces second quarter 2008 financial and operational results 13
... (Ser385) Immunogen: ... acid region encompassing the human, ... Accession Number: ... Quality Assurance: Routinely evaluated ...
Mouse monoclonal [MN-8C4] to zona radiata ( Abpromise for all tested applications). Antigen: Purified eggshell proteins (zona radiata proteins and small amounts of zona pellucida proteins) from ...
CCNI Antibody...
...
Biology Products: