POPULATION_DYNAMICSsssssssssssssssssssss.pptx

POPULATION_DYNAMICS

1. POPULATION DYNAMICS & CARRYING CAPACITY

2. What two major events are actually happening every second to make that number go up? Let’s Think. Discuss Click to access world clock

3. BENCHMARK(S): SC.912.L.17.5 Analyze how population size is determined by births, deaths, immigration, emigration, and limiting factors (biotic and abiotic) that determine carrying capacity. OBJECTIVE(S): Students will use data and information about population dynamics, abiotic factors, and/or biotic factors to explain and/or analyze a change in carrying capacity and its effect on population size in an ecosystem. Identify limiting factors and other population dynamics. What are we learning today?

4. ESSENTIAL QUESTION? How are population size influenced and controlled within the natural environment?

5. Before we talk about population and its limiting factors, we will go over the levels of organization. Simply put, the levels of organization explain how living things are organized from the microscopic to the macroscopic. Let’s Engage

6. LEVELS OF ORGANIZATION smallest unit of living things group of similar cells organized to work together group of different kinds of tissues working together group of organs working together one individual living thing all organisms of the same species living in one area Different interacting populations in an ecosystem all living and nonliving things interacting within a certain area large region with typical plants and animals that includes several ecosystems CELL COMMUNITY POPULATION ORGANISM ORGAN SYSTEM ORGANS TISSUE BIOME ECOSYSTEM

7. POPULATION DENSITY: The number of individuals in each area . 3 Types of Population Distribution Which is the most common form or distribution among organism? Why? Organism will clump together and is the most common form of distribution because: Availability of resources ( ex. Water or food ) Need for Protections ( safety in numbers ) Need for Reproduction ( need to be near opposite sex )

8. Population Dynamics The study how populations change in size due to birth rate / immigration and death rate / emigration and limiting factors (abiotic and biotic ) Birth Rate: (Number of people being born) Death Rate: (number of people dying) Immigration: (movement into an area) Emigration: (movement out of an area) • Increase in population : through birth or immigration . • Decrease in population : through death or emigration . Change in Population Birth + Immigration - Death + Emigration =

9. Limiting Factors of a population Limiting factors are environmental factors that tends to limit population size. Example: 1. Resources (Food and water) Can you think of some more?

10. Density-dependent Limiting Factor and Density-independent Limiting Factor Two types of limiting factors:

11. Density - Dependent Density-dependent Limiting factors : Factors that affects a population depending on the number of organisms in an area. Disease (How is the spread of disease dependent on number or organism in an area?) Habitat / Space (How is the loss of habitat or space dependent on number of organism in an area?) Competition ( Predator vs. Prey ) (How is competition for food or territory dependent on number of organism in an area?) Food & water (Resources) (How is the availability of food and water dependent on the number of organism in an area?)

12. How is the disease in “the walking dead” a density dependent factor? ***Disease, for example, can spread more quickly in a population with members that live close together or in larger population groups.

13. Density - Independent Density-independent Limiting factors: Factors that affect all populations, regardless of their density. Most density-independent factors are abiotic factors, such as: Extreme Temperature Extreme Weather Floods or Drought Major habitat disruption

14. How is this picture an example of a density- independent factor?

15. What is the carrying capacity ?

16. Graphing Populations: Populations tend to grow in two ways: Exponential Growth Curve “J” Shaped Rapid growth because of unlimited (many) resources. Rapid growth at first because of ample resources, but as resources become limited , its growth rate slows and levels off . Logical Growth Curve “S” Shaped

17. As resources become limited, growth rate slows and levels off. It has reached its CARRYING CAPACITY (K) . Closer look at Logistic Growth (“S” Shaped Curve) After a population reaches the carrying capacity, it often enters a state of dynamic equilibrium. This means the population's size will not be static but will instead fluctuate slightly above and below the carrying capacity as it responds to short-term changes in resource availability.