CHAPTER 2 POPULATION AND COMMUNITY DYNAMICS Flashcards
A group of interacting organisms of the SAME SPECIES living in a particular space
Population
Vary in size and character depending on the limits of space that they occupy
Population
Traits of Population?
- Particular gene flow as a result of inbreeding
- Has a life of its own, it establishes itself, grows, reaches a dynamic equilibrium, and declines
- Has a unique ways of allotting resources (eg. Food, space, mate)
- Able to regulate its own growth
- May have social behavior and cooperate for defense, nesting or hunting
A population can be characterized by its pattern of distribution or dispersion,dispersal, density and age structure.
True
The position or spacing of members of a population relative to their neighbors.
Dispersion
3 patterns of distribution?
Uniform distribution,
Random distribution
Clumped distribution
Occurs when individuals are more or less evenly distributed and happens when there is interspecific competition between individuals
Uniform distribution
Occurs when the presence of one individual does not influence others such as that the position of each individual is independent of the other and happen in a population where there is neither mutual attraction nor repulsion from territoriality
Random distribution
Aggregated, contagious, under dispersed and due to patchiness of environmental resources like food, moisture and habitat
Clumped distribution
Give an example of uniform distribution
Examples
Ø Birds are evenly distributed due to territorial habits
Ø Reptiles defend their exclusive territories
Ø Plants are evenly distributed to minimize competition of nutrients and sunlight
Give an example of random distribution
the randomly distribution of spiders and arthropods
in the forest floor
Give an example of clumped distribution
Examples: flock of birds, herd of cattle, school of fish, bed of flowers
When animal population increases, food resources become scarce resulting to intraspecific competition
Dispersal
Few individuals may evade such unfavorable condition by moving away and seeking better habitats called ?
Population dispersal
• The movement of individuals from a home site or birthplace to a new place
•It has a positive effect on the population as it decreases competition and eases pressure on feeding sites; inbreeding is also reduced
Dispersal
The movement of individuals from one place to another
Migration
The act of moving out from their original palce
Emigration
The movement of coming into or joining a population
Immigration
Migration has direct effect on population growth or
decline depending on the balance between emigration
and immigration
True
This are net increase in population
Greater immigration
This are net decrease in population
Greater emigration
The increase in number of individuals in a particular aggregation
Population growth
What are the three major factors of population growth?
Natality, mortality and survivorship
The growth is also facilitated by external factors like favorable climatic condition, elimination of natural enemies, nutritional quality
True