1. Populations

2. Population  Population is a group of organisms of the same species in an area.  To define a population you need to know  Type of individual  The time  The place  Population is a group of organisms of the same species in an area.  To define a population you need to know  Type of individual  The time  The place

3. Features of Population  Migration; movement of organisms into and out of the population.  Population Distribution and Abundance; density, distribution and total abundance.  Population Dynamics; population growth rate, Natality, mortility  Population composition; sex ratio, population fertility, age structure.  Migration; movement of organisms into and out of the population.  Population Distribution and Abundance; density, distribution and total abundance.  Population Dynamics; population growth rate, Natality, mortility  Population composition; sex ratio, population fertility, age structure.

4. Population Distribution And abundence Density Distribution Total abundance Population Composition Sex ratios Population fertility Age structure Migration Movement of individuals into and out of the population Population Dynamics Population growth rate, natality, mortility

5. Population Distribution and Abundance  Density; the number of organisms per unit area.  Distribution; the locations of individuals within an area.  Total Abundance; the total number of organisms.  Density; the number of organisms per unit area.  Distribution; the locations of individuals within an area.  Total Abundance; the total number of organisms.

6. Population Composition  Sex ratios; the number of organisms of each sex.  Population fertility; the reproductive capacity of the females.  Age structure; the number of organisms of different ages  Sex ratios; the number of organisms of each sex.  Population fertility; the reproductive capacity of the females.  Age structure; the number of organisms of different ages

8. Population Dynamics;  Natality (Birth Rate)  Mortility (Death rate)  Natality (Birth Rate)  Mortility (Death rate)

9. Natality  Natality is the number of birth per 1000 people per year.  Crude birth rate = # of births per yr X1000 total population  Natality is the number of birth per 1000 people per year.  Crude birth rate = # of births per yr X1000 total population

10. Mortility Rate  Mortility rate is the number of deaths per 1000 people a year  In humans this is; Crude death rate= Number of death per yr x1000 total population  Mortility rate is the number of deaths per 1000 people a year  In humans this is; Crude death rate= Number of death per yr x1000 total population

11. Population Growth Rate Births - Death + Immigration- Emigration

12. Population Regulation  Often populations are not able to continually increase in size.  Population sizes are regulated by many different factors  Often populations are not able to continually increase in size.  Population sizes are regulated by many different factors

13. Population regulation  Density dependent  Food supply  Disease  Competition  Predation  Density dependent  Food supply  Disease  Competition  Predation  Density independent  Rainfall  Temperature  Salinity  Catatrophic events  Density independent  Rainfall  Temperature  Salinity  Catatrophic events