by Staff Writers
Washington DC (SPX) May 22, 2017
Research published this week in Proceedings of the Royal Society B: Biological Sciences solves a mystery that has long shrouded our understanding of white oaks: where did they come from?
The approximately 125 white oak species in the Americas and 25 in Eurasia - including the massive bur oak of American prairies and savannas, the valley oak of California and the eponymous white oak of eastern North American forests - are important in forests and savannas throughout much of the northern hemisphere. Yet, despite their economic and ecological importance, not much was known about the evolutionary history of the white oak group until now.
This paper, co-authored by Andrew Hipp of The Morton Arboretum and Paul Manos and John McVay of Duke University, reveals for the first time that Europe and east Asia have eastern North America to thank for their white oaks.
Coupling genomic data with fossil records and novel analytical methods, the research suggests that the Eurasian white oaks arose from a North American ancestor that migrated to Europe, perhaps by way of the North Atlantic land bridge. This is a story that has long been hidden by ancient hybridization among the Eurasian white oaks. The research implements new analytical tools to tease apart hybridization from evolutionary history to tell the full white oak story.
The study, funded by a collaborative four-year National Science Foundation grant to five institutions led by The Morton Arboretum, also shows that two oak species found on opposite ends of the globe, the Armenian oak (Quercus pontica) found in the Caucasus mountains and Sadler's oak (Quercus sadleriana) of California and Oregon, are each other's closest relatives.
These species, the authors argue, are the last remnants of a widespread white oak lineage that stretched at least from Europe to the Pacific Northwest, of which all are extinct except for these two species.
"Understanding even the most basic questions - how many oak species are there? Where do they live? - rests on our understanding of oak evolution," said study co-author Andrew Hipp of The Morton Arboretum.
"This is the first paper to conclusively separate the role of gene flow and divergence to recover a holistic portrait of the white oak tree of life. It is a crucial step toward understanding why white oaks became so important to the ecology of temperate forests and savannas in the northern hemisphere."
Berkeley CA (SPX) May 16, 2017
A study led by ecologists at UC Berkeley has found significant flaws in the research used to challenge the U.S. Forest Service plan to restore Sierra Nevada forests to less dense, and less fire-prone, environments. Until recently, the consensus among forest ecologists was that before European settlers arrived in the Sierra, the forests were mostly open conifer forests dominated by big tree ... read more
The Morton Arboretum
Forestry News - Global and Local News, Science and Application
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|