Chapter 10 - Population Dynamics

What are some differences between a fundamental vs. realized niche? (Chapter 9 Review Question)

Fundamental Niches are possible locations while realizes niches are actual locations of where a species lives

What conditions might cause organisms to be regularly distributed across a landscape? (Chapter 9 Review Question)

Competition

Generally, population density increases with body size, True of False? (Chapter 9 Review Question)

False

Why might the distribution of organisms within their range exhibit clumped patterns? (Chapter 9 Review Question)

Resource distribution

What are three factors which would cause a species to be rare? (Chapter 9 Review Question)

1. Restricted Geographic Range

2. Narrow habitat tolerance

3. Small local population size

How do populations change over time?

They can expand, decline, or maintain stability

What is Dispersal?

The movement of organisms or their propagules

How does dispersal affect the distribution of a species?

Dispersal can increase or decrease local population densities.

How might we quanitify dispersal?

Measure the max distance travelled, average distances, rates of dispersal over time.

What do outliers signify when looking at a dispersal table?

Individuals that drive more population spread than normal

What's the difference between Immigration and Emigration when looking at dispersal?

Immigration refers to moving into a population while Emigration means to move out of a population

What are some techniques done in order to study historical dispersal?

Studying fossils and pollen records

What is a metapopulation and how does it differ from a community?

Metapopulations refer to groups of subpopulations that are connected via Immigration and Emigration, a community refers to multiple populations that interact with the environment.

What is Demography?

Study of births and deaths in a population

What are some tools used to study Demography?

Life Tables, Survivorship curves, and Age distributions

What is a Life Table? What do they plot?

A tool to study demography, summarizes survivorship and mortality (deaths). They plot survivorship curves

What is a Survivorship curve?

A table that shows the number of survivors for each age group, there are three types

Type 1 Survivorship Curve, what kinds of organisms exhibit this?

Young have a high survival that sharply declines as they get really old, exhibited by Humans and large mammals

Type 2 Survivorship Curve, what kinds of organisms exhibit this?

Linear survival decline as age increases, exhibited by birds and reptiles

Type 3 Survivorship Curve, what kinds of organisms exhibit this?

Young have low survival that decreases even further as age increases, exhibited by plants, fish, and invertebrates

Describe what a stable population looks like?

Many young and very few old

Describe what an unstable population looks like?

Very few young and many old

Net reproductive rate (R₀)

average number of offspring per female per lifetime.

Generation time (T)

average age of reproduction.

Per capita rate of increase (r)

rate of population growth, linked to R₀ and T.