Global Patterns Of Diversity

is an integrated, multidisciplinary scientific field that has developed in response to the challenge of preserving species and ecosystems

the variety of life, in all of its many manifestations… encompassing all forms, levels, and combinations of natural variation, at all levels of biological organization, this includes: - diversity within species -between species - and ecosystems

• ecological diversity • genetic diversity • organismal diversity

• biogeographic realms • biomes • provinces • ecoregion • ecosystems • habitats • populations

• populations -individuals • chromosomes • genes • nucleotides

• domains / kingdoms • phyla • families • genera • species • subspecies • populations • individuals

• encompasses the components of genetic coding that structure organisms • variability allows species to potentially adapt to changing. envr

• a group of individuals that can potentially breed and don’t breed with individuals of other groups • limits : fossil species + hybrids

a group of individuals that appear different from others, that is, are morphologically distinct - can be referred to as ‘morphospecies’

a group of individuals that share unique similarities in their DNA & their evolutionary past

the number of unique species in a collection or set of observations - difficult to measure, strongly influenced by sampling effort

number of species found per sampling effort (e.g. # of transects sampled, or # of days of sampling)

can be fit from a species accumulation curve to estimate how many species there might be (asymptotic richness)

species are weighted by some measure of their importance e.g. shannon- wiener index • when a community is dominated by only one or a few species, it may be that rare or uncommon species are at risk

• inventories are incomplete • described species tend to be larger bodied, more abundant, and more widespread • distributions are best known for temperate regions

ecological units based on dominant vegetation in terrestrial systems, and in the sea, on ocean currents and patterns of primary productivity

useful for assessing global biodiversity and ecosystem services

• locations with exceptional concentrations of endemic species that are undergoing exceptional loss of habitat • also consider ecosystem services provided + level of primary productivity

1 - contain at least 1,500 species of vascular plants found nowhere else on earth 2 - have lost at least 70% of its primary native vegetation

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• population dense • home to some of the world’s poorest communities • mostly rely directly on healthy ecosystems for their livelihood and well-being

• species richness of many taxonomic groups peak near the equator

including - historical perturbation - environmental stability - habitat heterogeneity - productivity - interspecific interactions

the amount of available energy in an area affects level of diversity –> energy availability generates and maintains richness gradients