Marine Adaptations

Marine animals that are warm-blooded have adapted to the cold and pressure in different ways. For example, some marine mammals (whales, dolphins, seals, and sea lions) have a blubber layer that protects them from the cold water. Other marine mammals such as sea otters have thick fur that creates a layer of air between the water and the animal's skin to keep them from getting cold. Marine birds also have this adaptation.

Marine animals that dive deep have adapted to the pressure by having very compressable gas spaces and a flexible skeleton that can collapse easily at depth. Scientists are still baffled by the dive patterns of the elephant seal - can repeatedly dive to 4000 ft. for hours at a time, without staying at the surface much. We are unsure how the animal can withstand such frequent changes in pressure and not get "the bends" like scuba divers do when nitrogen from depth accumulates in the blood stream.

Adaptations for Survival in the Sea

Camouflage - Many marine animals have colors that allow them to blend in with their environments. Some animals, such as a flounder, octopus, or grouper, can undergo color changes when they move to different surroundings or when they are angry or afraid. Camouflage coloring is also called crytic coloration.

Countershading - Open ocean or pelagic fish are often lighter on the bottom and darker on the top. This makes them harder to see in the water from either direction. A predator swimming under a fish looks up and sees the light-colored bottom which blends in with the sunlit water. Birds flying in the sky have trouble seeing the fish, too. Their dark tops blend in well with the water.