To: average joe who wrote (96630 ) 11/18/2012 1:42:00 AM From: Cogito Ergo Sum 1 Recommendation Respond to Maybe Megalodon like species will come back if we don't have a carbon tax :o)extinction remains under investigation. [10] Several possible causes for its decline and eventual disappearance have been proposed.[55] This trend may have been accelerated by changes in global ocean circulation caused by the closure of Central American Seaway [5] [56] and/or other factors (see Pliocene climate ), setting the stage for glaciation in the northern hemisphere. [56] Consequently, during the late Pliocene and Pleistocene, there were ice ages , [57] [58] which cooled the oceans significantly. [5] Expansion of glaciation during the Pliocene tied up huge volumes of water in continental ice sheets, resulting in significant sea level drops . [37] The major reason cited is the decline in ocean temperatures at global scale during the Pliocene. [5] [23] [59] This cooling trend adversely impacted megalodon, as it preferred warmer waters, [8] [59] and as a result it may have declined in abundance until its ultimate extinction during the Pleistocene. [59] Fossil evidence confirms the absence of megalodon in regions around the world where water temperatures had significantly declined during the Pliocene. [8] Furthermore, these oceanographic changes may have restricted many of the suitable warm water nursery sites for megalodon, hindering reproduction. [5] Nursery areas are pivotal for the survival of viviparian species. [60] en.wikipedia.org
