http://harvardscience.harvard.edu/topic/4167 Stories within a topic (RSS) en http://harvardscience.harvard.edu/animal-vegetable-mineral/articles/ants-are-surprisingly-ancient-arising-140-168-million-years-ago <!--paging_filter--><p>Ants are considerably older than previously believed, having originated 140 million to 168 million years ago, according to new Harvard University research published in the journal Science. But these resilient insects, now found in terrestrial ecosystems the world over, apparently only began to diversify about 100 million years ago in concert with the flowering plants, Harvard scientists say. <p>Led by Corrie S. Moreau and Naomi E. Pierce, the researchers reconstructed the ant family tree using DNA sequencing of six genes from 139 representative ant genera, encompassing 19 of 20 ant subfamilies around the world. <p>"Ants are a dominant feature of nearly all terrestrial ecosystems, and yet we know surprisingly little about their evolutionary history: the major groupings of ants, how they are related to each other, and when and how they arose," says Moreau, a graduate student in Harvard's Department of Organismic and Evolutionary Biology. "This work provides a clear picture of how this extraordinarily dominant - in ecological terms - and successful - in evolutionary terms - group of insects originated and diversified." <p>Moreau, Pierce, and colleagues used a "molecular clock" calibrated with 43 fossils distributed throughout the ant family tree to date key events in the evolution of ants, providing a well- supported estimate for the age of modern lineages. Their conclusion that modern-day ants arose 140 million to 168 million years ago pushes back the origin of ants at least 40 million years earlier than had previously been believed based on estimates from the fossil record.</p> Mon, 26 Mar 2007 06:26:16 -0400 70652986 3789 at http://harvardscience.harvard.edu