marine ecology unit 4

Porifera

sponges

Cnidaria

coral, sea anemones, siphonophores

Platyhelminthes

• flatworms, flukes, tapeworms

Nematoda

roundworms

annelida

segmented worms

Mollusca

chitons,snails, bivalves

Arthropoda

crabs, shrimp, barnacles

Echinodermata

sea stars, sea urchins, sea cucumbers

Chordata

 fish, tunicates

statoc’s

The major adaptation of most meiofauna is the____which is an organ that detects gravity and helps the organism differentiate up and down.

• Other adaptations include:

  • reduction in cell number, simpler anatomy

  • vermiform shape (elongated, wormlike)

  • neoteny - retention of larval form

  • haptic - ability to cling to grains by an adhesive material or hooks and claws

efficient reproduction - short life cycle, few gametes

limiting factors

temp-  the most extreme range occurs in intertidal beaches and minimally in subtidal sediments

salinity- particularly in intertidal areas where freshwater runoff occurs

wave action -  the most extreme range occurs in intertidal beaches and minimally in subtidal sediments

The most important factor determining the presence, absence, and types of meiofauna is______ .the coarser the grain size, the greater the volume of interstitial space, and therefore the greater the size and number of meiofauna.

grain size

Meiofauna, or interstitial organisms

are organisms that occupy the microspaces between particles or live on the individual particles.

seagrasses

flowering plants that adapted to live submerged in seawater. Seagrass beds are depositional environments, often with high organic content that can make the sediment under the bed anaerobic.

how are keels attached to the ocean

through a holdfast

kelp is in what type of regions

cold

what community has a hard substrate with low growing encrusting plants and animals

rocky subtidal

surface predators

•  are exposed at the surface and take organisms at or near the surface without disrupting the sediment structure

burrowing predators

•  move down various tubes or channels provided by the deep-dwelling prey and attack them

digging predators

• excavate holes to get food

infaunal predators

burrow through sediment and live in it at all times

a community that has a sandy, unstable substrate.  Benthic organisms in the sedimentary subtidal zone may be classified

sedimentary

what includes both motile and sedentary organisms that cause sediment to move and become resuspended

sediment destabilizers, or bioturbators,

• include various seagrasses whose roots bind sediments and frequently restrict burrowing animals (competitive interference)

sediment stabilizers

The health of freshwater and estuarine systems is often determined by analyzing the

benthic macro invertebrate

what is a benthic macro invertebrate

• A stream index can be calculated based on the relative abundance of different species

what is the largest phylum of life

arthropod

second biggest phylum

mollusk

Organisms that live on or above the substrate are called

• epifauna.

Organisms that live in the substrate are called

infauna,

macrofauna

• are greater than 0.5 mm

meiofauna

are 0.5 to 0.062 mm

microfauna

are smaller than 0.062 mm