Feb 16, 2011 Bring up your Invasive Species Analysis questions 1. What characteristic is used to define a biome?

Q: What are some characteristics of populations? All populations share the following characteristics Population density: how many organisms are in the area Spatial distribution: aka dispersion, how is the population spaced out in the area

Spatial Distribution Patterns Uniform (Spread Evenly)

Spatial Distribution Patterns Clumped (random groups clumped together like herds)

Spatial Distribution Patterns Random (unpredictable) Often determined by availability of resources

Q: What are some characteristics of populations? Population ranges: where the population can be found (no species can live everywhere!)

Q: What are some characteristics of populations? Population Limiting Factors Density Independent Factors Limiting factor that doesn’t depend on how many members there are in the population Usually abiotic (floods, drought, tornado, extreme heat, extreme cold, human activities, etc)

Q: What are some characteristics of populations? Population Limiting Factors Density Dependent factor Limiting factor that depends on how many members there are in the population Often biotic (disease, predation, competition, parasites, etc)

Q: What are some characteristics of populations? Population Growth Rate Tells us how fast the population grows To be determined you must know: Natality (birth rate) Mortality (death rate) These are helpful, but usually balance each other out. Emigration (how many are moving away) Immigration (how many are moving in)

Q: What are some characteristics of populations? Different models of growth Exponential Slow at the beginning, then shoots up J curve

Q: What are some characteristics of populations? Logistic Slow at beginning, shoots up, levels off S curve Levels when it reaches carrying capacity Maximum the environment can hold based on resources At carrying capacity, competition is at it’s greatest Births approx = deaths

Brain Pop

Homework Parts 3 – 5 of pkt