Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

DNA Study Sheds New Light on Horse Evolution

11.12.2009
Ancient DNA retrieved from extinct horse species from around the world has challenged one of the textbook examples of evolution – the fossil record of the horse family Equidae over the past 55 million years.

The study, published today in the Proceedings of the National Academy of Sciences, involved an international team of researchers and the Australian Centre for Ancient DNA (ACAD) based at the University of Adelaide.

Only the modern horse, zebras, wild asses and donkey survive today, but many other lineages have become extinct over the last 50,000 years.

ACAD Director Professor Alan Cooper says despite an excellent fossil record of the Equidae, there are still many gaps in our evolutionary knowledge. “Our results change both the basic picture of recent equid evolution, and ideas about the number and nature of extinct species.”

The study used bones from caves to identify new horse species in Eurasia and South America, and reveal that the Cape zebra, an extinct giant species from South Africa, were simply large variants of the modern Plains zebra. The Cape zebra weighed up to 400 kilograms and stood up to 150 centimetres at the shoulder blades.

“The Plains zebra group once included the famous extinct quagga, so our results confirm that this group was highly variable in both coat colour and size.”

Lead author of the paper, Dr Ludovic Orlando from Ecole Normale Supérieure of Lyon, says the group discovered a new species of the distinct, small hippidion horse in South America.

“Previous fossil records suggested this group was part of an ancient lineage from North America but the DNA showed these unusual forms were part of the modern radiation of equid species,” Dr Orlando says.

A new species of ass was also detected on the Russian Plains and appears to be related to European fossils dating back more than 1.5 million years. Carbon dates on the bones reveal that this species was alive as recently as 50,000 years ago.

“Overall, the new genetic results suggest that we have under-estimated how much a single species can vary over time and space, and mistakenly assumed more diversity among extinct species of megafauna,” Professor Cooper says.

“This has important implications for our understanding of human evolution, where a large number of species are currently recognised from a relatively fragmentary fossil record.

“It also implies that the loss of species diversity that occurred during the megafaunal extinctions at the end of the last Ice Age may not have been as extensive as previously thought.

In contrast, ancient DNA studies have revealed that the loss of genetic diversity in many surviving species appears to have been extremely severe,” Professor Cooper says. “This has serious implications for biodiversity and the future impacts of climate change.”

Professor Alan Cooper
Director
Australian Centre for Ancient DNA
University of Adelaide
Phone: +61 8 8303 5950
Mobile: +61 404 383 884

Professor Alan Cooper | Newswise Science News
Further information:
http://www.adelaide.edu

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>