Population Growth and Decline A PowerPoint Presentation by Mr. Jackson! BCHS
FACTORS OF POPULATIONS • Four factors determine the size of a population • at any given time. The factors are; • Death Rate • Migration • Birth Rate • Emigration Wow this sounds interesting!
Remember gang, population is the number of individuals living in the same space at the same time!
Death Rate The number of individuals that die within a specific time is known as the death rate.
Migration Migration of organisms that increase the population is known as immigration. Hey guys good to see you
Birth Rate Birthrate is the number of offspring produced by the population over a period of time. Birth rate can be affected by: • Nutrition • Environment • Density of population
Emigration These guys are all wet. I’m outa here! Departures of animals from the regular population is known a Emigration.
Limiting Factors Populations are limited by the the following influences: Abiotic Factors - Are the nonliving influences on populations such as Water, Matter and Weather. Biotic Factors - Are the ways living organisms might affect the size of a population, such as predators and parasites
Predation The relationship between predator and prey is know as predation. For a movie of a octopus eating a crab check here http://animalpicturesarchive.com/animal/AnimMovie/boct07tv.html For a close of Close up of a crocodile and a jaguar. http://animalpicturesarchive.com/animal/AnimMovie/clos00tv.html A cool animation of a great white shark swimming, http://animalpicturesarchive.com/animal/AnimMovie/sharks.html
Competition Animals naturally compete for limited biotic and abiotic resources. To find more information click on the button Reproduction Predators Next Human Impact Parasites
To Conclude To review the concepts click on the term Factors of populations Competition Limiting factors
Predators Predators consume other organisms for food energy
Parasites • These organisms live off others in different ways • Parasitism • Mutualisism • Commentialisim
Human Impact Humans are one of the few organisms that changes the environment to meet their needs. Can you list three ways we have done this?