Absolutely, Positively, TRUE I have personally found mastadon teeth in 130 feet of water 45 miles offshore Jacksonville, Florida. Average seal level rise 4' per century http://climatedepot.com/a/1245/Wash-Post-reporting-makes-progress-Article-concedes-sea-level-computer-model-predictions-could-be-flawed-or-flat-wrong http://www.fws.gov/slamm/Changes%20in%20Sea%20Level_expanded%20version_template.pdf http://www.texasbeyondhistory.net/coast/prehistory/images/sea-level.html