Biogeographic zones

Marine mammals have adapted to an aquatic or semi-aquatic lifestyle with such features as reduced or eliminated limb structures, a blubber layer for thermoregulatory, nutritional, buoyancy and locomotory roles, and reproductive strategies conducive to fitness in a given biogeographic zone (habitat). The environmental challenges faced by newborn marine mammals at birth may explain there largely precocious nature and the apparent maturity of the immune system of newborn marine mammals [1],... 

Three biogeographic zones have been defined to describe the spatial trends in the... 

Studies of fossils recovered from ocean cores indicate that zones based on planktic organisms are limited to biogeographic provinces. These provinces appear to be reflective of latitudinal distributions of water temperatures, and, to some extent, water masses. 

Events of biogeographical convergence like those described for Mesozoic ammonites (Cecca, 2002) or for plant and animal taxa from the Mexican Transition Zone... 

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