EQ: How is population size affected by limiting factors? Population Dynamics EQ: How is population size affected by limiting factors? ****Add predation, mutualism, paratism, commensulism
Population Dynamics KEY CONCEPT #1 Each population has a density and a dispersion strategy.
Population Density Population Density: the number of individuals that live in a defined area
Population Dispersion Population dispersion: How individuals in a population are spaced Clumped Random Uniform
Population Dispersion Draw an example of each type in your notes Clumped dispersion Uniform Random
KEY CONCEPT #2 Populations grow in predictable patterns. Population Dynamics KEY CONCEPT #2 Populations grow in predictable patterns.
Population Dynamics The size of a population is always changing. Four factors affect the size of a population Births Deaths Immigration emigration
Population Growth: Birth and Death Deaths- the number of individuals that die OUT of a population Birth- the number of individuals born INTO a population
Population growth: Immigration and Emigration- Emigration- the movement of individuals OUT of a population Emigration Exits Immigration-the movement of individuals INTO a population Immigration goes In E E I I
Population Growth: Stop and Think What do you think might cause rapid growth? Abundance of resources Teacher asks: What do you think might cause the rapid population growth? Answer: abundance of resources
Ecological factors limit population growth A limiting factor is something that keeps the size of a population down.
Density-Dependent Limiting Factors Factors are affected by the number of individuals in a given area. DEPENDS on the population size These are biotic or living factors
Density-dependent factors Competition: members of a population compete with one another for resources (food & shelter) Predation: the population of a predator can be limited by available prey (prey can be limited being caught) Parasitism and disease: can spread more quickly through dense populations eventually causing a decrease
Density Independent Limiting Factors Factors limit a population’s growth regardless of the density. INDEPENDENT of population size These are Abiotic or nonliving factors unusual weather natural disasters human activities
Carrying Capacity Carrying capacity: is the maximum number of individuals in a population that the environment can support. Occurs when the births/immigration are relatively equal to deaths/emigration A population crash is a dramatic decline in the size of a population over a short period of time. When a carrying capacity suddenly changes
Djibouti Activity C- level 2 voice with your table H- ask three before me A- Complete the Djibouti Activity and analysis questions Paste on left side of your notebook M- remain seated (butt on stool, stool on ground) P- work with your table group to complete lab SUCCESS Use bigger graph paper- easier to see the rice in each box
Exit Ticket Which of the following is a limiting factor in a population of organisms. A. reproductive replacement B. life spans of the members C. fluctuations in atmospheric temperature D. availability of food D. availability of food The availability of food is a limiting factor in a population of organisms. If there is not enough food, some of the organisms will die and the population will decrease in number
Exit Ticket How does the predator-prey relationship affect a population? A. The predators and prey are in competition with each other. B. Usually either the predator or the prey will become extinct. C. The predator species usually has exponential growth. D. The relationship controls the population size of both species. D.
Exit Ticket When an environment has reached its carrying capacity for a certain population, which of the following is true? A. Growth and immigration rate is equal to death and emigration rate. B. Growth and immigration rate is greater than death and emigration rate. C. Growth and immigration rate is less than death and emigration rate. D. Growth rate is exponential. A. Growth and immigration rate is equal to death and emigration rate. Carrying capacity is the maximum population size of a species that can exist in a given environment given the resources.
Exit Ticket The pH of the water in several lakes in Norway and Sweden had decreased to below 5.0 due to an increase in acid rain. Which of the following is most likely to happen in these lakes? A. the decline of several fish populations. B. an increase in numbers of fish C. an increase in the amount of primary producers D. increased predator-prey relationships A.