Biodiversity and Evolution Review

Biodiversity includes these components: – Functional diversity – Ecological diversity – Species diversity - Genetic diversity

Functional Diversity The variety of processes, including matter cycling and energy flow within ecosystems, that result from species interacting with one another in food webs

Ecological Diversity Variety of terrestrial and aquatic ecosystems found in an area or on the earth

Species Diversity The number and abundance of species present in different communities

Genetic Diversity The diversity that enables life on earth to adapt and survive environmental changes

Natural Selection Occurs when some individuals of a population have genetically based traits that enhance their ability to survive and produce offspring with the same traits.

Evolution A change in the genetic characteristics of a population from one generation to another

Mutations Random changes in the structure or number of DNA molecules in a cell that can be inherited by offspring.

Evolution by Natural Selection Review Genes mutate, individuals are selected, and populations evolve that are better adapted to survive and reproduce under existing environmental conditions.

Human Success Strong opposable thumbs Upright walking Complex brain

Survival of the Strongest Fitness – a measure of reproductive success

Geological Processes Volcanoes Earthquakes Mountains forming Fragmentation of forests Deforestation Construction Etc.

Extinction Entire species cease to exist Endemic species are found in only one area This makes them very vulnerable Mass extinction is a significant rise in extinction rates above the background level Large groups of species

Species Diversity Species richness – the number of different species vs… Species evenness - relative abundance of individuals within each species Higher the richness; the more sustainability

Ecological Niche The role a species plays in its ecosystem Don’t confuse with the species habitat Pattern of living

General vs. Specific Generalists have a broad niche Specialists have a narrow niche

Important Niche Roles Native species – thrive in a particular ecosystem; equilibrium Indicator species – provide early warning signs of damage Keystone species – large effect on types and abundance of other species Foundation species – shape and enhance habitats that benefit other species