In early 2015, 68 Experiment backers pitched $6,100 to support the study of mysterious stands of isolated aspen trees in the Willamette Valley, whose origin was unknown. The original hypothesis was that the trees were carried from Montana by floods nearly 15,000 years ago during the last ice age.
Steven Strauss at Oregon State University used the funding to gather data and do some DNA sequencing to figure out where the "lost aspens" came from. Using the DNA sequences from 183 individual trees, they constructed phylogenomic lineages for the Populus tremuloides forests.
Last week, the results were released as a pre-print in PeerJ and is also undergoing peer-review in a scientific journal. The core results demonstrate that the Willamette Valley aspen is part of a distinctive Pacific variety, which was previously unknown to science.
Their conclusions suggest that the aspens likely weren't carried by melting glacial floodwaters, as originally theorized. The project has added valuable information to the story of Earth's last ice age, back 11,000 years ago when Alaska and Russia were connected by a land bridge.
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