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Flashcards in Conservation biology Deck (38)
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1
Q

What is conservation biology?

A

It seeks to integrate evolutionary theory with environmental reality to predict how an animal/population/species will react to future/current changes, usually human caused, in its environment/density/distribution. Most importantly, whether it will survive and what to do to prevent extinction.

2
Q

What are the two main goals in conservation biology?

A

Investigate human impacts on biodiversity and develop approaches to prevent biodiversity loss.

3
Q

What are the levels in which biodiversity loss can occur?

A

Genetic diversity, species diversity and ecosystem loss.

4
Q

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

A

Background extinction patterns and mass extinction.

5
Q

What is background extinction patterns ?

A

The long pattern of ecosystem change that leads to some species going extinct.

6
Q

What is mass extinction patterns?

A

Catastrophic spikes of extinction associated with sudden widespread ecosystem change.

7
Q

What are some of the current estimates for the rate of extinction?

A

1 species an hour, 27000 species a year.

8
Q

What are the 4 major threats to biodiversity?

A

Habitat loss or degradation, introduced species, overexploitation and climate change.

9
Q

What is the largest threat to biodiversity?

A

Habitat loss and degradation.

10
Q

What is fragmentation?

A

The process by which a large continuous area is reduced and divided into two or more isolated patches.

11
Q

What does fragmentation result in?

A

Reduction in population sizes and genetic diversity, increasing likelihood of local extinction and eventually global extinction.

12
Q

What are the three types of pollution?

A

Land pollution, air pollution and water pollution.

13
Q

What is land pollution?

A

The release of chemicals that leave vast areas unusable for most organisms.

14
Q

What is air pollution?

A

Large scale effects that lead to widespread complex ecosystem alteration.

15
Q

What is water pollution?

A

Eutrophication and dead zones.

16
Q

Why can introduced species be a problem?

A

They displace native species, they have fewer predators/pathogens, the disrupt the ecosystem function, the reduce the overall diversity, they transmit disease.

17
Q

What are some invasive characteristics?

A

The are weedy/adaptable, they are common and they have rapid dispersal.

18
Q

What are some common UK invasive species?

A

The japanese knotweed, the asian hornet, the american mink and many plant pathogens.

19
Q

What is overexploitation?

A

When humans take wild plants or animals at rates that exceed the systems ability to replace them.

20
Q

What organisms and systems are vulnerable to overexploitation?

A

Large organisms with slow reproductive rates and aquatic and terrestrial systems.

21
Q

What is bycatch?

A

The fish caught in fishing that are not needed and may die when returned to the sea.

22
Q

Why is species distribution limited?

A

There are energetic costs, limited resource availability and the fitness of organisms is higher under optimal conditions.

23
Q

What are some of the outcomes of changing climatic conditions?

A

Range shifts, plastic responses, adaptation and extinction.

24
Q

What are the levels in which strategies can be developed to preserve biodiversity?

A

Species level, community level and ecosystem level.

25
Q

What results in definite extinction of an organism?

A

If in the long term the mortality and/or emigration rates are higher than the birth and/or immigration rates.

26
Q

What are the three extinction mechanisms that affect migration, mortality and birth rates?

A

Demographic uncertainty, environmental uncertainty and loss of genetic diversity.

27
Q

What are meta populations?

A

They describe fragmented population occupying spatially separate habitat patches.

28
Q

What is source/sink modelling?

A

Source populations provide an excess of individuals which emigrate to and colonize sink subpopulations.

29
Q

What is landscape modelling?

A

When the matrix vary in permeability.

30
Q

What does metapopulation survival depend on?

A

Local population survival (affected by genetics, patch size and quality - population increases with patch size), unoccupied suitable habitat and suitable distances and sufficient migration for colonization of unoccupied habitat to occur - increase with small distances and corridors.

31
Q

What are genetic factors affecting small populations?

A

Genetic drift, founder effects, bottleneck effects and inbreeding depression.

32
Q

What is genetic drift?

A

The change in frequency of an allele in a population due to random sampling.

33
Q

When are the effects of genetic drift significant?

A

In small populations as the random sampling of poor alleles leads to a chance of extinction.

34
Q

What does genetic drift increase the likelihood of?

A

That alleles are lost, reducing genetic variation within a population.

35
Q

What are founder effects?

A

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

36
Q

What is the bottleneck effect?

A

When there is a sudden reduction in population size due to a change in the environment. The resulting gene pool may no longer be reflective of the original populations gene pool. If the population remains small, it may be further affected by genetic drift.

37
Q

What is inbreeding depression?

A

The relative reduction in fitness of inbred progeny in comparison to an equivalent outbred progeny.

38
Q

What does the reduction in mating individuals after drift or bottleneck events result in?

A

The increased likelihood of mating among relatives, increasing the expression of deleterious traits causing fitness reduction.