Chapter 2 Principles of Ecology

 List 2 ways a population can decrease.  List 4 limiting factors.  Are humans r-selected or k-selected?  Differentiate between biotic potential and carrying capacity.  What are the levels of organization in an ecosystem?  List the 3 types and give examples of symbiosis.

 The total number of individuals living in a specific area  Example person/km2

 Randomly ex. Deer in the woods  Clumps ex. Elk on Highway 52  Uniformly ex. Birds on a wire

 Immigration- Organisms that move into a population  Emigration- Organisms that move out of a population  Mortality-similar to death rate; the number of organisms that have died  Natality- birth of organisms

 Growth that occurs very rapidly  Amount of time it takes for a population to double in size  Bacterial Growth.notebook Bacterial Growth.notebook

 R –selected – many babies for chance of survival  K –selected – few babies because have stronger habitats  Three types of Graphs  Type 1 – Few babies with long life  Type 2 – Normal Birth/Death rate (equal)  Type 3 – Many babies short lifespan

 The rate at which a population could grow if nothing was holding it back, no limits  No limiting factors (space, light,water, nutrients, and shelter)

 Carrying Capacity – maximum # of individuals of a special (population) that a given environment can sustain.  Population Growth – Maximum growth rate x number x Proportion of resources left  Density Dependent Control – factors that come into effect with population size.  Populations will grow to their capacity but they are dependent on outside factors (food, water, space, sunlight)

I. Organisms and Their Environment A. What is Ecology 1. Ecology - Scientific study of Interactions among organisms and their environments. *reveals relationships among living/non-living

B. Aspects of Ecological Study 1. Biosphere- portion of Earth that supports life

2. Abiotic factors- non-living parts of an organisms environment. *Often determine which species survive in a particular environment. Ex: Drought 3. Biotic factors- living organisms that inhabit an environment.

C. Levels of Organization in Ecology 1. Organism - individual 2. Population - Group of organisms of one species in the same place at a given time

3. Communities - group of interacting populations 4. Ecosystems - Communities and surrounding abiotic factors 1) Terrestrial - land 2) Aquatic - a) Freshwater b) Saltwater 5. Biosphere - all ecosystems

D. Organisms in Ecosystems 1. Habitat - place where an organism lives out its life 2. Niche - role a species plays in its environment *food it eats, shelter it uses, how it survives and reproduces

Symbiosis - Living Together 1. Commensalism - One species benefit, other is neither harmed or benefited 2. Mutualism - Both species benefit 3. Parasitism - One organism derives benefits at the expense of the other.

The living together of two different organisms

Not taking part or giving assistance when it comes to organisms living together. Gets along with other organisms, but do not give assistance to life in any way

A symbiotic relationship between two organisms of different species in which one benefits while the other is unaffected. Remora’s attaching to a shark

Barnacles on a whale Birds on a cow

An interaction between two or more species in which both species benefit from the other.

Acacia Tree – Ants live in the horns and bring nutrients to the tree while the tree gives them protection off the ground.

Introduction: Interspecific competition refers to the competition between two or more species for some limiting resource. This limiting resource can be food or nutrients, space, mates, nesting sites-- anything for which demand is greater than supply. A lion fending off a hyena for food.

A predator is an animal or other organism that hunts and kills other organisms, called prey, for food in an act called predation. Battle at Kruger

OUCH!!!! Snake vs Kangaroo

A symbiotic relationship in which one organism lives off of the other organism, but does not kill it. Parasites (mosquitoes & Head Lice) parasites

 List 2 ways a population can decrease.  List 4 limiting factors.  Are humans r-selected or k-selected?  Differentiate between biotic potential and carrying capacity.  What are the levels of organization in an ecosystem?  List the 3 types and give examples of symbiosis.