Arthur J. Jelinek, an anthropologist who took note of similarities between Solutrean and Clovis styles in a 1971 study, observed that the great geographical and temporal separation of the two cultures made a direct connection unlikely, since the dates of the proposed transitional sites and the Solutrean period in Europe only overlap at the extremes. He also argued that crossing the Atlantic with the means available at the time would have been difficult, if not impossible. The opinion is shared by Lawrence G. Straus, who wrote that "there are no representations of boats and no evidence whatsoever either of seafaring or of the ability to make a living mainly or solely from the ocean during the Solutrean". Straus excavated Solutrean artifacts along what is now a coastline in Cantabria, which was some ways inland during the Solutrean epoch. He found seashells and estuarine fish at the sites, but no evidence that deep sea resources had been exploited. Advocates state that the historic coastlines of western Europe and eastern North America during the Last Glacial Maximum are now under water and thus, evidence of Solutrean-era seafaring may have been obliterated or submerged.