the northern land bridge, summarize and cast doubts

the reading passage and the lecture are both about the time period of migration of people. the reading firmly arose some evidence that support the hypothesis. however the lecture repudiated of what stated in the reading passage with fallacious, premises and cast three counter claims as stated below. at first the reading passage claims that people might have migrated slowly across the grassy tundra of beringia, feeding on herds of animals or coastal marine life. in contrast, the lecturer acknowledged that several archaeological evidence found appears to be much older. that is the evidence was around 19000 years old which was long before the tools were made. as it took centuries for people to travel that far south it was around 15000 years old. by dating techniques it was found that the dates did not tally. additionally, the reading claims that the ending of ice age also caused ocean levels to rise thus submerging beringia and isolating new migrants from people on Asian side. the lecturer however argues that the oldest remains found was not of the native american's but were from northern islands and japan which resulted that there was diversity. although the diversity reduced at some time due to migration of course. on top of this, the reading claims that during the later centuries many subsequent finds of clovis tools demonstrate this culture's extensive penetration throughout the continent. the lecture however highlights that the syberian people migrated to america around 40000 years ago which is long before the clovis theory was even came to existence. these differences in the evidence found from different places contradicts the lecture from the theory in the reading.