[colorado tanker]

Well, there does appear to be a submerged ridge under the Yucatan Channel and Florida Straits.

http://images.google.com/imgres?imgurl=http://walrus.wr.usgs.gov/infobank/gazette/jpg/regions/fr_gm.jpg&imgrefurl=http://walrus.wr.usgs.gov/infobank/gazette/html/regions/gm.html&h=1832&w=2375&sz=1184&hl=en&start=9&tbnid=HcfnE04UTSP64M:&tbnh=116&tbnw=150&prev=/images%3Fq%3D%2Bsite:walrus.wr.usgs.gov%2Bgulf%2Bof%2Bmexico%2Bmap%26ndsp%3D20%26svnum%3D10%26hl%3Den%26lr%3D%26safe%3Doff%26rls%3DGGLG,GGLG:2005-45,GGLG:en

[blam]

This is a map of the world's oceans with the water level lowered by about 330 feet. Some say the water level was lowered by 500 feet during the Ice Age.