Biodiversity, Species Interactions, and Population Control

Secondary Ecological Succession

Series of communities or ecosystems with different species developing. (Usually

What are some examples of density independence?

Severe weather, fire and pollution.

Reproductive Time Lag

The period needed for birth rate to fall and for death rate to rise in response to overconsumption

Limiting Factor Principle

"Too much or too little of any physical or chemical factor can limit or prevent the growth of a population" (Even with other factors being in the optimal range of tolerance)

Mutualism

An interaction benefiting to both species by providing each with food, shelter or some other resource. (Nutrition and protection)

Commensalism

An interaction that benefits one species but has little to no effect on the other.

What are the four variables that govern changes in population size?

Births, deaths, immigration and emigration. (Population Change = (Births+Immigration)-(Deaths+Emigration)

What are three ways that members of a population are distributed?

Clumped, Uniform and Random.

Most common interaction between species.

Competition. Where niches overlap between diff. species.

Population

Group of interbreeding individuals of the same species.

Greater overlapping = Greater Competition

If one species ends up controlling most of the resources then the other must leave or develop new methods through adapting(natural selection), population decline or become extinct.

Whats are five basic types of interactions between species as they share limiting resources like food, shelter and space?

Interspecific Competition, Predation, Parasitism, Mutualism and Commensalism.

Primary Ecological Succession

Involves the gradual establishment of biotic communities in lifeless areas.

Population Density

Is the number of individuals in a population found in a particular area or volume.

Carrying Capicity

Maximum population of a given species that a particular habitat can sustain indefinitely.

Specialist (Narrow Niches)

Narrow niches and specialist species use less resources and are able to coexist with one another through resource partitioning.

Chemical Warfare

Other prey species use poison, thorns, gases or foul tastes to discourage predators.

What are some example of density dependent population control?

Parasitism, infectious disease and competition for resources.

Limiting Factor

Physical or chemical factor that can determine or regulate the population of a species.(Includes light, water, space, predators,temperature and nutrients)

How are age groups usually described?

Pre-reproductive age, reproductive age and the post-reproductive stage.

Carnivores

Pursuit,camouflage, chemical warfare or ambush mobile prey.

Clumps (Population Dispersion)

1: Resource availability varies from place to place. 2: groups have a better chance at encountering resources. 3: Clumps can provide protection from predators. 4: For predator species it is easier to hunt in a pack.

Age Structure

Distribution of individuals among various age groups.

Echolocation

Emission of high frequency pulses and high intensity sound which bounces off objects making it easier for certain species to navigate.

What are important physical limiting factors for aquatic life zones?

Temperature, sunlight, nutrient availability, salinity (amount of salts/minerals in water) and low levels of oxygen gas.

Environmental Resistance

The combination of all factors that act to limit the growth of a population.

Ecological Succession

The normally gradual change in species composition in a given area.

Range of Tolerance

The upper limit to which a species can tolerate a condition in the environment. (Temperature)

Prey Species

These types of species have developed a variety of ways to avoid predators including the ability to fly,swim, run, heightened sense of smell or sight, protective shells, thorns, camouflage or chemical warfare.

Herbivores

Walk,swim or fly to plants to feed on them.

What are some ways prey species can scare off predators?

Warning Coloration, Mimicry and Behavioral Strategies.

Predation

When a member of one species (Predator) feeds directly on all or part of a member of another species Prey)

Predation-Prey Relationship

When a member of one species preys on another. (Brown Bear and Salmon)

Overshoot

When a population exceeds the carrying capacity

Population Crash

When a population suffers a sharp decline.

Exponential Growth

When a population with little to no limitations on its resources begins to grow at a fixed rate.

Parasitism

When one organism (Parasite) feeds on another organism (Host), usually by living on or in the host.

Coevolution

When populations of two competing species interact for a long period of time giving way to changes in both their gene pools.

Resource Partitioning

When species competing for the same scarce resources develop specialized traits that allows them to coexist and share. By either using certain parts, using the resources at diff. times or using them in diff. ways.(Honeycreepers of Hawaii)

Interspecific Competition

When two or more members interact to gain access to the same limiting resources such as food, water , light and space.