New species evolving three times faster in Australia and South Africa<em>- News release</em>
See also...
Imperial College London news release
Strictly embargoed for
22.00 hours GMT
(17.00 hours US Eastern Time)
Monday 22 December 2008
New species of flowering plants called proteas are exploding onto the scene three times faster in parts of Australia and South Africa than anywhere else in the world, creating exceptional 'hotspots' of species richness, according to new research published today in Proceedings of the National Academy of Sciences (PNAS).
Proteas are best known as the national symbol of South Africa. The international team behind today's new study created an evolutionary 'family tree' of all 2,000 protea plant species on Earth – the majority of which are found in South Western Australia (SWA) and the Cape Floristic Region (CFR) of South Africa. This 'family tree' enabled the researchers to examine how these and other regions of the planet with Mediterranean-style climates have become so- called 'biodiversity hotspots'.
Until now, scientists have not known exactly why such large numbers of plant and animal species live in these Mediterranean hotspots. They are places of significant conservational importance which, like the rainforests, contain some of the richest and most threatened communities of plant and animal life on Earth.
The majority of protea species on Earth are found in the two regions studied by Dr Savolainen
The research published today provides the first conclusive proof that plant species in two of these hotspots are evolving approximately three times faster than elsewhere on the planet. The study dates this surge in protea speciation as occurring in the last 10-20 million years, following a period of climate change during which SWA and the CFR became hotter, drier, and more prone to vegetation fires.
Dr Vincent Savolainen, a biologist based at Imperial College London and the Royal Botanic Gardens, Kew, one of the authors of the new study, explains its significance, saying:
"Something special is happening in these regions: new species of proteas are appearing notably faster than elsewhere, and we suspect this could be the same case with other plant species too. This study proves that the abundance of different kinds of proteas in these two areas isn't simply due to normal rates of species diversification occurring over a long period of time.
"This is the first step towards understanding why some parts of the planet with a Mediterranean-style climate have become species-rich biodiversity hotspots."
Dr Savolainen and his colleagues believe that climatic changes millions of years ago could be one of the factors that prompted the protea plants' 'hyperdiversification' in SWA and the CFR. As these two regions became hotter, dryer, and prone to seasonal fires, proteas – which are drought-resistant and able to re-grow easily after a fire – would have survived, thrived and diversified into new species when faced with less competition for resources from less hardy plants.
Dr Savolainen concludes: "South Western Australia and the Cape Floristic Region of South Africa are areas of great interest to both evolutionary biologists and conservationists, because they contain such a rich profusion of life but are under threat from mankind's activities.
"Understanding more about the evolutionary history of these biodiversity 'hotspots' is important because it can help make conservation efforts more efficient."
Proteas live in the southern hemisphere and come in many different shapes and sizes, from 35-metre-tall trees to low growing shrubs. All proteas have leathery leaves and cup-shaped groupings of small, brightly coloured flowers that resemble thistles.
The Cape Floristic Region of South Africa and South Western Australia are two of five areas on Earth with a Mediterranean-style climate which have been designated 'biodiversity hotspots' by Conservation International. The others are: central Chile, California, and The Mediterranean basin.
For more information please contact:
Danielle Reeves, Imperial College London press office
Tel: +44 (0)20 7594 2198
Out-of-hours duty press office: +44 (0)7803 886248
Email: Danielle.reeves@imperial.ac.uk
Chloe Kembery, Royal Botanic Gardens press office
Tel: 020 8332 5607
Mobile: 07909 910 782
Email: c.kembery@kew.org
Notes to Editors:
1. 'Contrasted patterns of hyperdiversification in Mediterranean hot spots', Proceedings of the National Academy of Sciences, early online publication, 22 December 2008.
Herve Sauquet (a,b,c), Peter H. Weston (b), Cajsa Lisa Anderson (d), Nigel P. Barker (e), David J. Cantrillc(f), Austin R. Mast (g), and Vincent Savolainen (a, h).
(a) Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond TW9 3DS, United Kingdom;
(b) National Herbarium of New South Wales, Botanic Gardens Trust, Mrs Macquaries Road, Sydney NSW 2000, Australia;
(c) Department of Palaeobotany, Swedish Museum of Natural History, P.O. Box 50007, 104 05 Stockholm, Sweden;
(d) Department of Systematic Biology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, SE-752 36 Uppsala, Sweden;
(e) Department of Botany, Rhodes University, Grahamstown 6140, South Africa;
(f) National Herbarium of Victoria, Royal Botanic Gardens, Melbourne, Private Bag 2000, South Yarra, Victoria 3141, Australia;
(g) Department of Biological Science, Florida State University, Tallahassee, FL 32306;
(h) Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire SL5 7PY, United Kingdom.
2. About Imperial College London
Consistently rated amongst the world's best universities, Imperial College London is a science-based institution with a reputation for excellence in teaching and research that attracts 12,000 students and 6,000 staff of the highest international quality.
Innovative research at the College explores the interface between science, medicine, engineering and business, delivering practical solutions that improve quality of life and the environment - underpinned by a dynamic enterprise culture.
Since its foundation in 1907, Imperial's contributions to society have included the discovery of penicillin, the development of holography and the foundations of fibre optics. This commitment to the application of research for the benefit of all continues today, with current focuses including interdisciplinary collaborations to improve health in the UK and globally, tackle climate change and develop clean and sustainable sources of energy.
Website: www.imperial.ac.uk
3. About the Royal Botanic Gardens, Kew (RBG Kew)
Kew is a UNESCO-inscribed World Heritage Site and houses over 40 listed buildings and other structures including the Palm House, Temperate House, Orangery and Pagoda as well as two ancient monuments, Queen Charlotte's Cottage and Kew Palace. RBG Kew is a world famous scientific organisation, internationally respected for its outstanding living collection of plants and world-class herbarium as well as its scientific expertise in plant diversity, conservation and sustainable development in the UK and around the world. For more information visit www.kew.org
Article text (excluding photos or graphics) available under an Attribution-NonCommercial-ShareAlike Creative Commons license.
Photos and graphics subject to third party copyright used with permission or © Imperial College London.
