1. LO’s - the meaning of ecology, population symbiotic relationships - can explain population demographics and ways in which population sizes are regulated. - can explain various types of symbiotic relationships. Ecology Population

2. Ecology Study of the interactions between organisms and the environment Study of the physical and biological variables governing the distribution & growth of living things

3. Population Individuals of a given species occurring at one place at one time Population ecology – Study of population growth & interactions

4. Population Is a groups of individual of the same species that live in the same area

5. 1.Population Density: 2.Spatial Distribution: Dispersion: The pattern of spacing a population within an area (Way that individuals are arranged 3 main types of dispersion Clumped Uniform Random Population Characteristics Number of organisms per unit area Density influences survival

6. Individuals evenly spaced Often results from territoriality Also plants with allelopathy Lacking definite order Individuals do not influence others growth Individuals form clusters Clumping due to interaction of individuals

7. Population Limiting Factors 3.Population growth rate – How fast a given population grows – Factors that influence this are: Natality Mortality Emigration - movement out of a population Immigration - movement into a population

8. Population Size (births + immigrants) – (deaths + emmigrants) = Population change Immigration – movement into a population Emigration – movement out of a population

9. Carrying Capacity Indefinite exponential growth is limited Shortages of growth factors will limit population growth Carrying capacity = maximum number that can be supported in a particular environment

10. Population size (births + immigrants) – (deaths + emigrants) = Population change

11. Boom & Bust Cycle Sometimes populations do not level off Exponential growth with a sudden die-off

12. Interactions Within Communities Community Grouping of populations living together in a particular area at a particular time

14. Abiotic Factors Nonliving factors within the environment – Air – Water – Rocks Abiotic factors affect living (biotic) factors

15. Biotic components are the living things that shape an ecosystem. Biotic factor - any living component that affects another organism - needs energy to do work and food for proper growth - Plants, animals, fungi, protiste and bacteria

16. Ecosystem Biotic & abiotic factors in a certain area Biotic and abiotic factors combine to create a system (ecosystem)

17. Habitat Space within an area where an organism lives Each organism plays a certain role

18. Niche Two ways of defining – An organism’s role in the environment – Organism’s use of biotic & abiotic resources

20. Density Dependent Factors Factors that affect a population only if its density changes Types of density dependent factors – Competition – Predation – Parasitism

21. Competition Interaction among organisms for the same resources – Food – Living space Regulates population size & is a driving force of evolutionary change

22. Competition Types Intraspecific – among the same species Interspecific – between species

23. Predation One species will kill & eat another Interactions maintain natural populations More prey results in more predators Less prey reduces predator numbers

24. Parasitism One species living at the expense of another Regulates populations by weakening or killing

25. Symbiosis is a close relationship between two or more different species. There are 3 types of symbiosis we will discover: Commensalism—A relationship where one species obtains food or shelter from the other species. Does not harm or help the other species. Mutualism—A relationship where both species benefit from the relationship Parasitism-- A relationship between two species in which one species (the parasite) nourishes itself to the disadvantage of the other species (the host).

26. Demography Statistical study of human population Human population is in exponential growth

27. Human Population Growth has Different Patterns Stable population – Remains the same – Same number entering reproductive age as at end of reproductive age Population pyramid – Graphic representation of population age – Shows patterns in population change

28. Biotic and abiotic factors are interrelated. If one factor is changed or removed, it impacts the availability of other resources within the system