The researchers, led by Dr Robin Allaby from the University of Warwick's plant research arm Warwick HRI, examined Archaeobotanical remains of ancient barley at Qasr Ibrim in Egypt's Upper Nile. This is a site that was occupied for over 3000 years by 5 successive cultures: Napatan, Roman, Meoitic, Christian and Islamic.
The first surprise for the researchers was that throughout that period every culture seemed to be growing a two rowed form of barley. While natural wild barley tends to be two rowed most farmers prefer to grow a much higher yield 6 row version which produces up to 3 times as many grains. That 6 row version has grown for over 8000 years and that was certainly grown in the lower Nile over the same period as Qasr Ibrim was occupied. It was thought that despite the fact that the rest of Egypt used 6 row barley that the farmers of Qasr Ibrim were perhaps deliberately choosing to import 2 rowed barley but the researchers could not understand why that would be so.
The plant scientists were pleased to find that the very dry conditions at Qasr Ibrim meant that they were able to extract a great deal of DNA information from barley samples from the site that dated back 2900 years. This was far better than would normally be expected from barley samples of that age. This led to the researchers to a second and much bigger surprise. They found that the DNA evidence showed that the two rowed barley at the site wasn't the normal wild two eared barley but a mutation of the more normally cultivated six rowed barley that had changed into a two ear form that had continued to be cultivated for around three millennia.
Dr Robin Allaby said:
"The consistency of the two-row phenotype throughout all the strata spanning three millennia indicates that the reason for the reappearance of the two row form is more likely to be genetic, not environmental. Consequently, the two-row condition has probably resulted from a gain of a function mutation at another point in the plants DNA that has also reasserted the two-row condition from a six-row ancestor"
"There may have been a natural selection pressure that strongly favoured the two-row condition. One such possible cause we are currently investigating is water stress. Qasr Ibrim is located in the upper Nile which is very arid relative to the lower Nile where six-row remains are found, and studies have shown that two-row can survive water stress better than six-row"
He concluded that:
"This finding has two important implications. Such strong selection pressure is likely to have affected many genes in terms of adaptation. Archaeogenetic study of the DNA of such previously lost ancient crops could confirm the nature of the selection pressure and be very valuable in the development of new varieties of crops to help with today's climate change challenges. Secondly this crop's rediscovery adds to our respect for the methods and thinking of ancient farmers. These ancient cultures utilized crops best suited to their environmental situation for centuries, rather than the much more popular six rowed barley they used a successful low grain number yield crop which could cope far better with water stress."
The research paper entitled "Archaeogenetic Evidence of Ancient Nubian Barley Evolution from Six to Two-Row Indicates Local Adaptation" has just been published in PLoS One. The papers authors are: by Dr Robin Allaby, Sarah A. Palmer and Jonathan D. Moore from the University of Warwick's plant research arm Warwick HRI; Alan J. Clapham from Worcestershire Historic Environment & Archaeology Service at the University of Worcester; and Pamela Rose fromThe McDonald Institute for Archaeological Research, University of Cambridge.For further information contact: Dr Sharon Hall, Communications Office
Sharon Hall | EurekAlert!
Oestrogen regulates pathological changes of bones via bone lining cells
28.07.2017 | Veterinärmedizinische Universität Wien
Programming cells with computer-like logic
27.07.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
Spectrally narrow x-ray pulses may be “sharpened” by purely mechanical means. This sounds surprisingly, but a team of theoretical and experimental physicists developed and realized such a method. It is based on fast motions, precisely synchronized with the pulses, of a target interacting with the x-ray light. Thereby, photons are redistributed within the x-ray pulse to the desired spectral region.
A team of theoretical physicists from the MPI for Nuclear Physics (MPIK) in Heidelberg has developed a novel method to intensify the spectrally broad x-ray...
Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.
Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
26.07.2017 | Event News
21.07.2017 | Event News
19.07.2017 | Event News
28.07.2017 | Health and Medicine
28.07.2017 | Power and Electrical Engineering
28.07.2017 | Life Sciences