Species diversity = the number of different species in a particular area at the particular time
Genetic diversity = variety of genes amongst all the individuals in a population of one species
Habitat diversity = range of different habitats
Species richness = the number of different species in a particular area at a particular time
What is an advantage to good genetic diversity ?
Lots of alleles for different genes, so the population has a better chance of being able to adapt to environmental changes
What are 3 causes of genetic diversity decreasing ?
Genetic bottle necks
Captive breeding
Founder effect
Founder effect = small number of individuals from a population colonise a new isolated area. This decreasing gene pool and increases chance of inbreeding
Captive breeding = small number of breeding individuals, same alleles will be passed on
Geneticbottlenecks = only a small number of population survive an event, gene pool is decreased as only survivors can pass o their alleles
How do you calculate genetic diversity ?
Examine the polymorphic genes within isolated population. The higher the proportion of polymorphic gene loci, the larger the genetic diversity.
Polymorphic gene = gene that has more than one allele
Monomorphic gene = gene with only one allele
What does simpson index measure ?
Species evenness and richness
When you have calculated Simpson index, what does a large value of D represent ?
The larger the value of D, the greater the species diversity
What must you consider when getting a representative sample ?
sample size is large enough
random sampling to avoid bias
Opportunistic sampling = sampling organisms that are conveniently available
What is an issue with opportunistic sampling ?
Bias, so unlikely to be representative of population
Stratfied sampling = population / habitats can be seperated into groups and then random sampling occurs
Systematic sampling = used when there is a change in distribution of species within the habitat
What can quadrants be used to sample ?
slow moving organisms and plants
name 4 methods of animal sampling ?
Pond dipping
sweeping nets
pitfall traps
pooters
species evenness = the relative amount of each species in a population
Name 3 factors that affect biodiversity ?
Human population increase
Agriculture
Climate change
Name 3 reasons to maintain biodiversity ?
ecological (all species are interdependant on each other )
asthetic
economical
in situ conservation = conservation that occurs within the natural habitat
Give an example of in situ conservation ?
wildlife reserve
What is a benefit to insitu conservation ?
maintains genetic diversity
Which is the preferred form of conservation ?
insitu
Ex situ conservation = removing organisms from their natural habitat to try and protect them
Give 3 examples of ex situ conservation ?
botanical gardens
seed banks
captive breeding
Botanical gardens = provide optimal growing conditions for plants
Seed banks = store seeds in water +temperature controlled environments. Back ups of genetic material incase of extinction or need for cross breeding
What is the Purpose of CITES ?
Regulates the trade of international animals, plants and their products, it prevents endangered species being transported
What 3 agreements were made at the Rio convention on bio diversity ?
countries must come up with strategies for sustainable development
stabilise greenhouse gas emissions
prevent destruction of fertile land into desert and reduce effect of drought
Why is the lack of genetic diversity between crops an issue for farmers ?
The crops are highly susceptible to disease.
There are fewer adaptation opportunities
The soil becomes depleted of nutrients.
What is a keystone species ?
A species that has a key role in maintaning the structure of a community.
name 2 aesthetic reasons to maintain biodiversity ?
Enrichment of lives and pleasure
Inspiration for artists
Name 3 advantages to insitu conservation ?
Maintains genetic diversity
Cheaper than exsitu
Preserves species relationship with other species.