Conservation biology

Question 1

What is conservation biology?

Answer 1

Multidisciplinary science developed to deal with alarming loss in biodiversity

Question 2

What are the 2 major goals of conservation biology?

Answer 2

> Investigate human impacts on biodiversity

>Develop approaches to prevent biodiversity loss

Question 3

What are the 3 levels of biodiversity loss?

Answer 3

> loss in genetic diversity
loss in species diversity
ecosystem loss

(loss in levels affects one another)

Question 4

What are the 2 patterns of extinction in the geological record?

Answer 4

Background extinction
= long pattern of ecosystem change that leads to some species going extinct
= normal extinction rate

Mass extinction
= catastrophic spikes of extinction with sudden widespread ecosystem change

Question 5

What is the opposing argument to us being in the 6th mass extinction?

Answer 5

No. of genera increasing over time

BUT this is due to finding new orgs and making a new genera to describe them

Question 6

What is the current extinction rate?

Answer 6

1 species an hr
27000 species a yr
100-10,000x background rate

Question 7

How is genetic diversity within species lost?

Answer 7

Reduction in effective population sizes
-> smaller no. of alleles in population
= higher chance of going extinct

Question 8

What are the 4 major threats to species loss?

Answer 8

> Habitat loss/degradation (incl. pollution)

> Introduced species (incl. disease)

> Overexploitation (harvesting/hunting)

> Climate change

Question 9

Which is the biggest threat to species?

Answer 9

Habitat loss + degradation

98% of land suitable for agri has been transformed

Question 10

What affect does fragmentation have?

Answer 10

Causes reduction in population sizes + genetic diversity
-> increases likelihood of local extinction
+ eventually global extinction

Question 11

What are the 3 types of pollution?

Answer 11

Land
- release of chemicals leaves areas unusable by orgs

Air

Water
- eutrophication + dead zones

Question 12

Why are introduced specie a problem?

Answer 12

>Displace native species
>Have fewer predators/pathogens
>Disrupt ecosystem function
>Reduce overall diversity 
>Transmit disease

Question 13

What is overexploitation?

Answer 13

Humans taking wild plants + animals at rate that exceeds system’s ability to replace them

Question 14

Which orgs are most susceptible to overexploitation?

Answer 14

Large orgs with slow reproductive rates

Question 15

What limits a species’ distribution?

Answer 15

Energetic costs
Resource availability
Fitness higher under optimal conditions

Question 16

What are the possible outcomes if climate conditions change?

Answer 16

> Range shifts = ranges where species are present
Plastic responses = change response to environment w/out changing genetic make-up
Adaptation = change eugenic make-up
Extinction

Question 17

What are the 3 mechanisms of extinction categories for single populations?

Answer 17

Demographic uncertainty
Environmental uncertainty
Loss of genetic diversity

Question 18

What is a metapopulation?

Who introduced this concept?

Answer 18

a group of populations that are separated by space but consist of the same species

Levins

Question 19

What is the source/sink model of metapopulations?

What is the landscape model?

Answer 19

Source populations provide excess individuals which emigrate to + colonise subpopulations

Matrix varies in permeability

Question 20

What does metapopulation survival depend on?

Answer 20

Local population survival
-> increases w/ patch size

Unoccupied sutabale habitat at suitable distances

Sufficient migration for colonisation of unoccupied habitat to occur
-> increases w/ small distances + corridors

Question 21

What are the 4 genetic factors affecting small populations?

Answer 21

Genetic drift
Founder effects
Bottleneck effects
Inbreeding depression

Question 22

What is genetic drift?

Answer 22

Change in freq of an allele in a population due to random sampling

• increases chance of alleles being lost
• significant in small populations

Question 23

What is the equation for effective population size?

Answer 23

Ne = (4Nf x Nm) / (Nf + Nm)

Question 24

What is the founder effect?

Answer 24

When few individuals become isolated from the larger population to form new one

-> allelic diversity

Question 25

What is the bottleneck effect?

Answer 25

Sudden reduction in population size due to change in environment

Question 26

What is inbreeding depression?

Answer 26

Relative reduction in fitness of inbred progeny in comparison to an equivalent outbred progeny