WASHINGTON — The Clovis people, known for their distinctive spear points, likely were not the first humans in the Americas, according to research placing their presence as more recent than previously believed. Using advanced radiocarbon dating techniques, researchers writing in Friday’s issue of the journal Science said the Clovis people, hunters of large Ice Age animals such as mammoths and mastodons, dated from about 13,100 to 12,900 years ago. That would make the Clovis culture, known from artifacts discovered at various sites including the town of Clovis, N.M., both younger and shorter-lived than previously thought. Previous estimates had dated the culture to about 13,600 years ago. These people long had been seen as the first humans in the New World, but the new dates suggest their culture thrived at about the same time or after others also in the Americas. Michael Waters, director of Texas A&M University’s Center for the Study of the First Americans, called the research the final nail in the coffin of the so-called ‘Clovis first’ theory of human origins in the New World. Waters said he thinks the first people probably arrived in the Americas between 15,000 and 25,000 years ago. […]