Name:_________________________________________________ Ecology Unit, Chapter 14 Notes

14.1: Habitat and NicheKey Concept: Every organism has a habitat and a niche

What’s the difference between a habitat and a niche?

______________________: All of the biotic & abiotic factors in the area where an organism lives (i.e. grass, trees, watering hole)

______________________: Includes the same as the habitat. (All of the physical, chemical, and biological factors that a species needs to survive, stay healthy, and reproduce), ______________________________________________________________ (i.e. type of food species eats, temperature it can tolerate, time of day it is active, how it interacts with others)

Habitat is where a species ___________________ (“address”), niche is _______________ it lives there (“job”)

14.2: Community InteractionsKey concept: Organisms interact as individuals and as populations.

Competition & predation are two important ways in which species interact.1. Competition: Two organisms fight for the same limited resources.

Intraspecific: members of the __________________ species Interspecific: ____________________________ species

2. Predation: One organism captures and feeds upon another organism.

Symbiosis is a close ecological relationship between two or more organisms of different species that live in direct contact with one another. Three types of symbiosis:

_____________________________ : Both species benefit from one another. Example: bat & cactus Commensalism: One species benefits from the other, the other is neither ___________________________.

Example: Humans & demodicids _____________________________: One organism benefits while the other is harmed. Ex.: Tapeworms

_______________________________ : Live in the tissues and organs of the host Ectoparasite: Lives on the _________________________ of the host

14.4: Population Growth PatternsKey concept: Populations grow in predictable patterns

Population size changes. Why? Increased Population 1. __________________________: Movement of individuals into a population from another population

Ex: fruit flies and banana

2._____________________: increases the number of individuals in a population. Ex; additional flies born

Decreased Population

3. _______________________________: Movement of individuals out of a population and into another populationEx: some flies get out.

4. ___________________: the size of the population decreases when individuals die. Ex; fruit flies get squashed.

The rate of growth for a population is directly determined by _________________________________________.

Types of Population Growth Exponential Growth – occurs when individuals

reproduce at a __________________________________________________________________; population size increases dramatically over a period of time.

*J-curve, human population

Logistic Growth – population rises exponentially and then growth slows when it reaches its ______________________________________________.

*Carrying capacity: The maximum number of individuals of a particular species that the environment can

_______________________________________________________________.*S-shaped Curve

What affects the carrying capacity of a population? Factors that have the greatest effect at keeping down the size of a population are called

___________________________________________________. They can be ________________________________________or ____________________________________________________.Density-dependent limiting factors:

*Affected by the number of _____________________________ in a given area.

Fruit Fly Population Growth

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Rabbit Population Growth

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*Examples: Competition, __________________________, parasitism, ______________________

Density-independent limiting factors:*Aspects of the environment that limit population growth _____________________________________.

*Examples: Unusual weather, natural disasters, __________________________________.

14.5 Ecological SuccessionKey concept: Ecological succession is a process of change in the species that make up a community.

Succession occurs following a disturbance in an ecosystem. Succession: the sequence of biotic changes that regenerate a _______________________ community or

create a community in a previously ___________________________ area.*Primary succession:

The establishment and development of an ecosystem in an area that was previously __________________.

Can begin due to melting glaciers, ______________________________, or landslides. First organisms to live in a previously uninhabited area are called pioneer species.

Examples: lichens and mosses that can break rock down into smaller pieces.

*Secondary Succession: The reestablishment of a ____________________ ecosystem in an area where the soil was left intact. Plants and other organisms that remain start the process of regrowth. Small disturbances start the process ______________________________. Example: forest fire, tree falling