2. SPECIES DIVERSITY
- number or variety of species in a particular region.
Species diversity
- number of different species that are represented
in a given community (a dataset)
-incorporates both the number of species in a
community (species richness)and the
evenness of species‘ abundances.
3. Factors
• Speciation
-is the evolutionary process by which new biological
species arise.
• Extinction
-is defined as “the reduction of a species to such low
abundance that, although it is still present in the
community, it no longer interacts significantly with other
species.
• Migration
- is the moving of individuals of a species from one place
to another.
Species diversity
4. Factors
• Immigration
- is the migration seen as the settling in one region
(permanently or temporarily) of individuals coming from
another region.
• Emigration
is the migration seen as an exit of individuals from one
region (to another where they will settle permanently or
temporarily).
*Therefore individuals emigrate "from" and immigrate "to".
Species diversity
5. Influences
• Species Richness
-the number of species that live in a certain location.
- a count of species, and it does not take into account the
abundances of the species or their relative abundance
distributions.
• Relative abundance
-is the number of individuals of each species.
-refers to how common or rare a species is relative to
other species in a defined location
Species diversity
7. Hotspots for Species Diversity
Species diversity
• The hottest spots for species diversity
are tropical rainforests.
Tropical rainforests comprise of only 7% of
all land on Earth, yet are home to nearly 50% of
all the species on Earth!
