Class Test 1 Flashcards
Describe the Allee Effect
It occurs in small or sparse populations and is characterized as a positive correlation between population size and mean individual fitness of the population.
A strong Allee effect can cause critical population sizes.
Allee effects can be caused by a variety of mechanisms which affect reproduction and survival. E.g mate limitation
Who was dubbed “The father of conservation”?
Aldo Leopold
What three aspects make up the ‘Conservation Triangle’?
Politics and society (Ethics); Management (Physical) and Conservation Biology (Science)
Define ‘Biodiversity’
The variety among living organisms from all sources, including diversity within a species, between species and in an ecosystem.
What are the three levels of biodiversity?
- Genetic diversity
- Species diversity
- Community diversity
What are three consequences of the loss of biodiversity?
- Interbreeding depression
- Loss of individual populations
- Reduced potential to evolve
What are the three concepts for the definition of a species? And what is their general statement?
- The Biological Species Concept - Species are defined by reproductive isolation
- Phenetic Species Concept - Species are defined by mophological similarities
- Phylogenetic Species Concept - Species are defined by the smallest visible monophyletic group
What are the three types of species diversity? And what do they each measure?
- Alpha diversity - measure species richness at one site
- Beta diversity - measure of diversity gradient between sites
- Gamma diversity - measure of the rate of diversity change in the whole ecosystem
What are three consequences of population growth?
- Increased need for space
- Increased need for resources
- Increased waste
When was the 6th mass extinction? And what were the two possible causes?
During the Pleistocene and the beginning of the Holocene.
Two possible causes were - human activity and environmental change
What was the cause of island extinctions?
Humans
What were two of the environmental changes which could have caused ancient continental extinctions?
Glacial retreat and the Younger Dryas event
Name four types of human activity which is affecting the environment, ecosystems and diversity
- Agriculture
- Industrialisation
- Urbinisation and sprawl
- International traffic and trade
Define ‘over-exploitation’
The non-sustainable use of a resource to the point of deminishable return
Explain the concept of ‘economic drive’
A market is established and begins to make profit…
increased interest in the market due to profit….
increased exploitation of the resource….
stocks collapse…..
move on to new resource.
What are three examples of over-exploitation?
- Whaling
- Over-fishing
- Trade in wildlife products
What does CITES stand for?
Convention on international trade in endangered species
What are the three appendices of the CITES and what do they entail?
Appendix I: trade in these products is not permitted
Appendix II: trade in these products is strictly limited
Appendix III: trade in these products is monitered
Define ‘Autogenic engineers’
Vegetation or some animals which create habitats for other species
Define ‘Allogenic ecosystem engineers’
Animals which drastically change a habitat
Define ‘Deterministic extinction’
When the entire habitat is destroyed and no species or communities remain (rare)
Define ‘Stochastic extinction’
When the habitat is only partially destroyed and increases chance of extinction
What are the three patterns of habitat fragmentation? Name an example for each.
- Patches (e.g logging in Bolivia)
- Waves (e.g agricultural clearing in the Amazon)
- Dissection (e.g motorways in Britain)
Name at least 3 effects of habitat fragmentation on populations
More isolation Demographic stochasticity Reduced fitness (Allee effect) Genetic stochasticity (genetic drift and loss of diversity) Metapopulation dynamics
What is the BDFFP and what did it discover?
Biological Dynamics of Forest Fragments Project
They discovered the Edge Effect
What is the ‘Edge Effect’?
Edges are different to interior habitats, there is increased invasion, altered climate and increased passive emigration. Increased edges leads to changes in species community.
Define ‘Biomagnification’
The accumulation of a substance during a lifetime and within a food chain
Define two chemicals which demonstrated biomagnification and state where they came from
DDT - in pesticides
PCB - in fridges and freezers
What are three traits of an invasive species?
- High reproduction rate
- Good dispersal
- Low specialisation
What are five traits of a community which makes is more likely to be invaded?
- In early stages of succession with empty niches
- Low diversity
- Low stability
- Remote
- Naive to predators
Name some examples of invasion in nature
Harlequin Ladybirds Ruddy ducks Crayfish Lampreys Zebra Muscles
Describe what a ‘protected area’ is
An area which is specially dedicated to the protection and management of biological diversity
What is the WCPA?
The World Commission on Protected Areas
What is the IUCN?
The International Union for the Conservation of Nature
What does IUCN protected area category Ia stand for?
Strict nature reserve - for science only
What does IUCN protected area category Ib stand for?
Wilderness area
What does IUCN protected area category II stand for?
National Park
What does IUCN protected area category III stand for?
Natural monument
What does IUCN protected area category IV stand for?
Habitat/species management area
What does IUCN protected area category V stand for?
Protected Landscape/seascape
What does IUCN protected area category VI stand for?
Managed resource protected area
Give an example of an Ia protected area
Aldabra Atoll, Seychelles
Give an examples of an II protected area
Kaziranga National Park, India
Give an example of a V protected area
Snowdonia National Park, Wales