Marine Ecology: Tropical Communities and Symbiotic Relationships

What are the two types of corals?

hermatypic and ahermatypic

What type of coral produce reefs?

hermatypic

What type of coral has a symbiotic relationship with zooxanthellae?

hematypic

What type of coral are found throughout the world?

ahermatypic

What type of corals do not produce reefs?

ahermatypic

What type of corals do not have a symbiotic relationship with zooxanthellae?

ahermatypic

What mineral do coral produce?

calcium carbonate (limestone)

Why does coral produce calcium carbonate?

to create a protective outer shell

Which marine ecosystem has the largest biodiversity in the world?

coral reefs

What are six major physical factors that limit coral reef development?

temperature, depth, light, salinity, sedimentation, emergence

What is the temperature coral reefs can withstand?

23-25 degrees Celsius

What is the depth coral reefs can withstand?

40m

What is the salinity that coral reefs can withstand?

>25ppt

What are the horseshoe shaped reefs that rise out of deep water, creating a lagoon?

atolls

Where do atolls frequently form?

around volcanic islands that have subsided

Barrier reefs are adjacent to what, separated by what?

landmasses, deep water channel

What are fringing reefs adjacent to?

landmasses

What is the difference between fringing and barrier reefs?

Fringing reefs are closer to landmasses and not separated by water channels

Almost all hermatypic corals are what?

colonial

What are the individual animals that make up corals?

polyps

What type of planktivores feed during the day?

diurnal

Diurnal planktivores have eyes close/far to the head.

close

Diurnal planktivores have small/large upturned mouths.

small

Diurnal planktivores have teeth-filled/toothless jaws

toothless

How do diurnal planktivores reduce predation?

show interspecific convergence and spines on their fins

Name an example of a Diurnal planktivore

damselfish (butterfly fish, surgeonfishes)

What kind of planktivores feed during night?

nocturnal

Nocturnal planktivores have larger/smaller eyes.

larger

Nocturnal planktivores have which two colorations?

red and silver

What are some examples of nocturnal planktivores?

squirrel fishes (big-eyes, cardinalfishes)

What do the herbivorous coral reef fishes consume?

plant material that grows on the reef

Why do herbivorous have a longer digestive tract?

plant matter is harder to digest

Herbivorous fish have small/large mouths?

small

Herbivorous fish have what kind of bodies?

laterally compressed

What are some examples of herbivorous fish?

parrotfish (triggerfishes, blennies)

What type of fish have the highest degree of feeding specialization?

carnivorous

What are the three categories of carnivorous fish?

pickers, crunchers, piscivores

What type of carnivorous fish feed on small benthic crustaceans?

pickers

What type of carnivorous fish includes the families damselfishes and butterfly fishes?

pickers

What type of carnivorous fish crush the shells of sponges and tunicates?

crunchers

What type of carnivorous fish include pufferfish and wrasses?

crunchers

What type of carnivorous fish feed on other fish?

piscivores

What are the inshore marine communities dominated by several species of halophytic trees and shrubs?

mangroves

Mangroves have shallow roots that spread widely and send up extensions called what?

pneumatophores

What allows mangrove trees to reach the surface to get to the oxygen in the anoxic substrate?

pneumatophores

What is the interrelationship between two different species which are generally either harmless to either member, or, more likely, beneficial to one or both?

symbiosis

What is an association that is clearly to the advantage of one member while not harming the other member?

commensalism

What is the form of symbiosis in which two species associate for their mutual benefit?

mutualism

All known symbiotic relationships in the sea between plants and animals are between what?

unicellular algae or their chloroplasts and a wide variety of marine invertebrate animals

The algal cell symbionts have been classified by what?

color

What color are zooxanthellae?

brown, golden, or brownish-yellow

What color are zoochlorellae?

green

What color are cyanellae?

blue or bluish-green

Marine commensals that live on other invertebrates are called what?

epizoites

What are the marine creatures that live inside other animals but are not parasitic called?

endozoites

The light produced by bacteria is normally continuous, so what do the marine animals do to counter this?

develop elaborate modifications to control the light (reflective surfaces, screens or shades)

are very common fish on coral reefs; particularly popular because it is very colorful. They feed primarily on sponges, but juveniles will act as a symbiont in cleaning parasites off other fish.

Queen Angelfish

are another very common family of reef fish. is easily identified by their long snout and distinct eye spot. Eye spots are an adaptation to confuse

predators.

Yellow Longnose Butterflyfish

tropical halophyllic tree that can be found as far north as

North Carolina, but are most common in the estuaries and coastlines of tropical Florida. They are well known for their stilt roots, also

called prop roots, which raise them up above the waterline.

Red Mangrove Tree

Every night, certain species of this fish envelope themselves in a transparent cocoon made of

mucous secreted from their head. Much of the sand on beaches is actually ground up, undigested coral that it excretes.

Parrotfish

is a common coral species found throughout the Caribbean and up the southeast

coast of the United States, including North Carolina. As with all corals, they need clear, warm waters to facilitate their symbiotic

relationship with zooxanthellae

Star Coral

are very vulnerable, slender fish that come out at night to feed on plankton. During the

day, they live inside invertebrate hosts. These include sea cucumbers, to whom they have a commensalistic relationship

Pearlfish

1. Although corals are sessile organisms, they engage in a behavior pattern that we usually associate with mobile organisms. This

behavior is

a. nesting b. sexual reproduction c. migration d. sleep

b

2. Coral reefs worldwide are experiencing rapid overgrowth by fleshy macroalgae. Which of the following are possible reasons for

this?

a. nutrients have been added to the water column

b. coral coverage has been reduced by disease and physical disturbance

c. reduction in algal herbivores

d. all of these answers

d

3. All of these statements are true of symbiotic luminescent bacteria except

a. the bacteria obtain food from their hosts

b. the bacteria inhabit mainly squid and fish of the mesopelagic zone

c. the bacteria are passed to the next generation through the egg

d. the bacteria produce light constantly

c

4. The physical structure of coral reefs is the result of a complex balance among which of the following processes?

a. climate and sea level change

b. calcification, compaction/cementing, and bioerosion

c. predation, competition and disturbance

d. calcification and dissolution

b