Marine Bio- Day 3&4
 Drill: Compare and contrast the epipelagic and
mesopelagic zones.
 Outcome: Discuss the zones of the ocean by classifying
marine organisms
 Agenda:
 Review Ocean Zones
 Explain Marine Lifestyles
 Possible Brief intro into food chains and webs
Pelagic Zone
Marine Lifestyle
 Marine life is incredibly diverse. Scientists use groups and subgroups based on
common physical characteristics to discuss them. Three types of lifestyles
include:
1) Plankton are the group of organisms that exist adrift the ocean currents.
^ Neuston are those plankton that float at the surface, for example Portuguese
Man-of –War.
Plankton
Marine Lifestyle cont.
2) Nekton are the organisms that swim, from small invertebrates to large whales.
Most of the seas’ predators are Nekton. The majority of Nekton are vertebrates.
Marine Lifestyle cont.
3) Benthos are organisms that live on or in the bottom. They can move about
or be sessile. Sessile organisms are attached to the sea floor.
Marine Lifestyle cont.
 Benthos are divided into three categories:
1) Epiphauna – are those animals, such as crabs, that live on the sea floor.
2) Infauna – are organisms that are partially or completely buried in the sea
floor… such as clams, sand dollars, tubeworms, and sea pens.

Most Infauna are either “deposit feeders” or “suspension feeders.” (Deposit feeders feed off
detritus down from above. Suspension feeders filter particles (mostly plankton) suspended in
the water for food.)
Epiphauna, Epiflora, or Infauna?
Infauna – Sea Pens
Epifauna – Sea Star
Infauna – Sand Dollar
Epifauna – Crab