220 likes | 322 Views
19.1 Understanding Populations. 1. Population Properties. Size (often hard to measure). 1. Population Properties. Size (often hard to measure) Density – amount of population per unit of area (population crowding) # of individuals = population density area (units 2 ).
E N D
1. Population Properties • Size (often hard to measure)
1. Population Properties • Size (often hard to measure) • Density– amount of population per unit of area (population crowding) # of individuals = population density area (units2)
1. Population Properties • Size (often hard to measure) • Density– amount of population per unit of area (population crowding) # of individuals = population density area (units2) • Dispersion – spatial organization of the population
1. Population Properties • Dispersion – spatial organization of the population
1. Population Properties • Dispersion – spatial organization of the population • Clumped – population is clustered together, usually around resources or from social behavior • ex/ school of fish
1. Population Properties • Dispersion – spatial organization of the population • Uniform – the population is evenly dispersed from each other usually from social interactions • ex/ bird nesting sites or solitary predators
1. Population Properties • Dispersion – spatial organization of the population • Random – the population is randomly scattered throughout the area • ex/ trees in a forest with seeds dispersed by wind or animals
2. Population Dynamics • Age Structure • the number of individuals of different ages within the population
2. Population Dynamics • Age Structure • the number of individuals of different ages within the population • different age groups may have different abilities such as birth/death rates
2. Population Dynamics • Survivorship Curve • probability of individuals surviving to a certain age
2. Population Dynamics • Survivorship Curve • probability of individuals surviving to a certain age • I – Low birth rate, low infant mortality, survives to old age (Humans & large mammals)
2. Population Dynamics • Survivorship Curve • probability of individuals surviving to a certain age I – Low birth rate, low infant mortality, survives to old age (Humans & large mammals)
2. Population Dynamics II – Survivorship rate equal at all ages (Birds & reptiles)
2. Population Dynamics II – Survivorship rate equal at all ages (Birds & reptiles)
2. Population Dynamics III – High birth rate, high infant mortality rate (Fish, Insects, Plants)
2. Population Dynamics III – High birth rate, high infant mortality rate (Fish, Insects, Plants)