#27 Diversity of marine fauna Flashcards
what makes marine communities unique
fluid medium
3 dimensional environment
vast spatial scales
what are unique characteristics of marine fauna
high fecundity - large numbers of offspring
large population sizes
dispersing individuals young and underdeveloped
high adult vagility
large range sizes
what is the hierarchy of biodiversity
- genetic diversity: diversity within genes of a species
- species diversity: how many marine species are there? this varies across marine environments
- community/ecosystem diversity: there will be varieties of ecosystems and diversity within them. different habitats within the community
where is lots of marine diversity in Aus.?
lots of marine diversity in northern Australia
lots of islands here
lots of islands give costal species places to live
what is the coral triangle
in the indo-pacific
area of high habitat diversity
lots of coral reefs for habitat
why are there so many species in the ocean
there is heterogeneity in the ocean - a range of habitats and niches for a species to occupy depending on what it needs
what are the primary drivers of heterogeneity
temperature
habitat availability - coastal
ocean basin age and history - coastal
what are the 3 hypothesis behind the indo-pacific diversity hotspot (coral triangle)
- centre of origin: speciation of species in this area has lead to species richness
- centre of accumulation: species have migrated here over time
- centre of overlap: Australia and Asia were once seperate regions. over time they overlapped, hence creating lots of diversity
what is the intermediate disturbance hypothesis
diversity is best at medium levels of disturbance
diversity is low at high disturbance and at low disturbance frequencies
what are poifera and what are their features
sponges few tissues, no organs skeleton of spicules sessile filter feeders form habitat and nutrient recyclers
what are cnidaria and their features
jellyfish, anemones
possess nematocysts - stinging cells
two body forms - medusa and polyp form
what are annelida and their features
segmented worms
segmented bodies
soft bodied
what are arthropoda and their features
crustacea - crabs, lobsters crayfish hard exoskeleton segmented bodies grow by moulting food source for humans
what are mollusca and their features
gastropods - bivavles such as snails, sea slugs
soft body with external shell
have mantle
radula tongue for prey or algae
cephalopods such as squid and octopus
have an internal shell
octopus dont have bony structures
hunters - predators
what are bryozoa and their features
lace corals
colonial animals
live in a calcified structure for their house
