Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What...
Transcript of Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What...
![Page 1: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/1.jpg)
Populations Introduction to Population Dynamics
![Page 2: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/2.jpg)
I. Populations A. What is a population?
• The world is divided into millions of species.
• Within a species, a population is a group of individuals that are actually available to each other for mating. ��� • A species may be spread across the globe, while a���population tends to���cluster together.
![Page 3: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/3.jpg)
B. Examples
![Page 4: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/4.jpg)
C. Population Dynamics
1. Populations grow when birth rate + immigration rate (# of
organisms moving into a population) > death rate + emigration
rate (# of organisms moving out of a population)���
2. Populations decline when birth rate + immigration rate (# of
organisms moving into a population) < death rate + emigration
rate (# of organisms moving out of a population)
![Page 5: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/5.jpg)
A. Populations and Resources
• Resources determine how a given population will grow.
• In general, any population of organisms with plenty of resources and ideal conditions tends to grow fast.
II. Population Growth
• This type of growth is called exponential growth.
![Page 6: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/6.jpg)
B. Doubling Time
• Exponential growth has a fixed doubling time. There is a certain
number of days, or months, or years in which the population
doubles.
![Page 7: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/7.jpg)
C. Exponential Growth
• At first the population grows slowly, but at some point it takes
off.
![Page 8: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/8.jpg)
1. Resources, matter and energy in short supply limit how large a
population can grow, therefore resources can be ���
limiting factors.
A. No population can continue exponential growth forever
because resources are finite.
III. Limiting Factors
![Page 9: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/9.jpg)
1. Density-dependent limiting factors control population size when a population is large and crowded. a. examples: competition, predation, parasitism and crowding
2. Density-independent limiting factors control population size regardless of whether a population is large or small. a. examples: natural causes such as geothermal activity, extreme weather
B.
![Page 10: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/10.jpg)
IV. Carrying Capacity & Population Growth
A. Carrying Capacity
• Limiting factors determine the carrying capacity, or the number
of individuals in a population that can be sustained indefinitely in
a given ecosystem.
![Page 11: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/11.jpg)
• When a population is small compared to the carrying capacity, it
grows rapidly. What happens next depends on many factors.
![Page 12: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/12.jpg)
B. J Curve
• The population slows as it approaches the carrying capacity and
levels off, reaching a steady state.
![Page 13: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/13.jpg)
C. J Curve
• A period of rapid population increase followed by collapse.
• Population growth disrupts the ecosystem so badly that its
carrying capacity is reduced, and the species suffers a die-off
from which it never fully recovers.
![Page 14: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/14.jpg)
J Curve Example
![Page 15: Introduction to Population Dynamics · Introduction to Population Dynamics! I. Populations! A. What is a population? ! • The world is divided into millions of species.! • Within](https://reader034.fdocuments.us/reader034/viewer/2022042605/5f45ae75fc427e599151405b/html5/thumbnails/15.jpg)
gThe End