marine biodiversity

Question 1

what is biodiversity

Answer 1

• the complete range of species and biological communities
• Genetic variation within species – all of species of a given area
• The range of ecosystem processes – all different biological communities + all processes involving the chemical and physical env

Question 2

what is a species

Answer 2

• Morphological species – group of individuals that are physiologically distinct from other groups in some key characteristic
• Biological species – group of individuals that can breed with each other in the wild but not with other groups of individuals

Question 3

what is a population

Answer 3

Group of interbreeding inds of a given species at a sight

Question 4

what is a Community / assmblage

Answer 4

Groups of pops, of multiple species at a given site

Question 5

2 main reasons biodiversity is important

Answer 5

• Intrinsic value – has its own worth regardless of worth
• Anthropocentric values

Question 6

5 Anthropocentric values biodiversity gives

Answer 6

• Vulnerability – removal of biodiversity weakens the system – yields further loss
• Renewable resources – food, fibre, medicines, natural products
• Ecosystem goods + services – a way to put monetary value on the natural world (Direct + indirect use values)
• Insurance – destroyed biodiversity might mean we lose something critical to our survival
• Ethical value – should not endanger our own environment – moral responsibility to protect the environment and other species

Question 7

8 taxonomy levels

Answer 7

3 Domains – eukarya, archaea, bacteria
6 Kingdoms
Phyla
Class
Order
Family
Genus
Species

Question 8

what makes up a scientific name

Answer 8

Genus (capital) + species (lower case)

Question 9

who came up with the taxonomic levels

Answer 9

Linnaeus 1758

Question 10

how many phyla are in the Marine environment

Answer 10

31

Question 11

phyla Porifera characteristics

Answer 11

e.g. sponges
- no symmetry
- filter feeders
- sessile
- few tissues
- marine + freshwater

Question 12

phyla Cnidaria characteristics

Answer 12

e.g. corals, sea fans, jellies, sea pansies, anemones
- radial symmetry
- nematocytes (sting)
- simple nervous systems
- primitive body systems
- mouth no anus

Question 13

phyla Bryozoans characteristics

Answer 13

e.g. sea moss, sea mats
- sessile
- colonial
- marine + freshwater
- U shaped gut
- filter feeders

Question 14

phyla Platyhelminthes characteristics

Answer 14

• parasitic / free living
• bilateral symmetry
• some organs
• mouth no anus

Question 15

phyla Nematoda characteristics

Answer 15

e.g. round worms + threadworms
- unsegmented
- meiofaunal
- complete gut
- parasitic/free living
- 1,000,000 species

Question 16

phyla Mollusca characteristics

Answer 16

e.g. gastropods, bivalves, cephlapods
- bilateral symmetry
- mantle (organs are kept)
- complete guts
- shell/shell plates/epidermal spicules

Question 17

phyla Arthropoda characteristics

Answer 17

e.g. decapods
- segmented bodies
- jointed limbs
- hard exoskeleton
- complete gut

Question 18

phyla Annelids characteristics

Answer 18

e.g. segmented worms
- bilateral symmetry
- can regenerate
- eye-like sensory organs
- complete gut
- hairs

Question 19

phyla Echinoderms characteristics

Answer 19

e.g. sea stars, urchins
- 5-ray radial symmetry
- no head
- subepidermal plates
- water vasular system
- exclusively marine

Question 20

phyla Chordata’s 2 groups

Answer 20

Tunicata + Vertebrata

Question 21

group Tunicata characteristics

Answer 21

e.g. sea squirts, ascidians, larvaceans, salps
- sack-like bodies
- filter feeders
- notochord (spine-like structure)

Question 22

group Vertebrata characteristics

Answer 22

e.g. fishes, birds, mammals
- backbone

Question 23

abundance meaning

Answer 23

number of individuals

Question 24

density meaning

Answer 24

number of individuals / unit area

Question 25

biomass meaning

Answer 25

mass of living organisms in an area

Question 26

what is the distribution of species on earth

Answer 26

25% of species marine 75% terrestrial - But more phyla in marine env than land – all but 3 phyla are marine + 1/3 of phyla are exclusively marine

Question 27

how are the majority of organisms distributed in the ocean

Answer 27

98% = benthic (associated with seafloor) 2% pelagic (water collumn)

Question 28

how do we describe benthic organisms and its 4 groups

Answer 28

by size not taxonomy - Megafauna – cm e.g. fish - Macrofauna – 250-500um e.g. polychaetes - Meiofauna – 32-62um e.g. nematodes - Microbiota - microns e.g. protists

Question 29

how does benthic organism abundance vary vertically (by depth)

Answer 29

- Slight decrease in abundance as depth increases - Bacteria (Microbiota) most abundant in all depths

Question 30

how does benthic organism biomass vary vertically (by depth)

Answer 30

- Benthic biomass has stronger decrease with depth - 0-2000m = macrofauna most biomass - >2000m = bacteria most biomass

Question 31

how does macrofaunal diversity vary vertically (by depth)

Answer 31

- increases until reaches Mid depth maximum in diversity - then decreases - Depth varies - 2000-3000m

Question 32

how do Benthic organisms vary horizontally (geographically)

Answer 32

- Equator = max richness – decreases at the poles - Hotspots in Indo-west pacific + Indian ocean

Question 33

what are the Challenges to assessing biodiversity

Answer 33

- underestimated the number of species living in the deep sea - modern estimates = 2.2 million species in the ocean

Question 34

3 biggest needs in marine biodiversity research

Answer 34

- Taxonomic training and expertise + jobs - New technologies + exploration research (funding) - Foster collaborations + communications internationally

Question 35

recent developments in marine biodiversity research

Answer 35

Dna sequencing pools: - dna barcoding (mito COI gene) - metabarcoding (species ID) / metagenomics (functional genes)