Tagged zooplankton


  — the research teased out these details by using 21,946 fossil specimens from areas of nevada in the us and the yukon in canada that were once ancient sea beds to paint a picture of graptolite evolution. the analysis found that as ocean circulation patterns began to shift hundreds of thousands of years before the ordovician extinction, graptolite communities that previously included a rich array of both shallow- and deep-sea species began to lose their diversity and complexity. read article : zooplankton warn us, extinction has a tipping point