Cenozoic Oceans. Early Cenozoic animals include massive creatures like the Megalodon Shark. Whales and marine mammals diversify in this era. All modern organisms in todays oceans are present.
Benthos:organisms that live at the bottom of oceans or bodies of fresh water. (Sea urchins, Sea stars, sea cucumbers, sand dollars, crabs, lobsters, shrimp, most bivalves).
Intertidal and Sublittoral Zone: zones where most life is found. Why?
Bathyl Zone: Not much life can survive here but squid, octopus, and whales can flourish.
Both abyssal and hadal zones have very few life forms but some life does exist.