population demography and dynamics

28
Population Demography and Dynamics Adan, Fatima Ellese Jerusalem, Czar Alfeo Solisa, Valerie

Upload: mariel-marjes

Post on 27-Dec-2014

118 views

Category:

Education


5 download

DESCRIPTION

 

TRANSCRIPT

Page 1: Population demography and dynamics

Population Demography and

DynamicsAdan, Fatima Ellese

Jerusalem, Czar AlfeoSolisa, Valerie

Page 2: Population demography and dynamics

Demography • From the word “Demo” and “graphy”

• It includes the study of how a population changes over time.

Population Dynamics

• Population fluctuations from year to year or place to place

Page 3: Population demography and dynamics

Factors Affecting Population Demography

• Fertility •Mortality • Immigration • Emigration

Page 4: Population demography and dynamics

Population Growth

• Population growth is affected by:–sex ratio–Generation time

Page 5: Population demography and dynamics

Sex Ratio• In a study conducted by Joseph Elkinton,

J. H. Myers and G. Boettner• egg masses of forest caterpillars from

low-density sites produced significantly more females than those from high-density sites, for which the numbers of males and females were equal or slightly in favor of males.

Page 6: Population demography and dynamics

Sex Ratio• The female bias of the sex ratio of

low-density populations increases the potential rate of increase of the population and may arise from local mate competition when populations are sparse.

Page 7: Population demography and dynamics

Generation Time

• Short generation time results in the increase in population growth rate but can be diminish more rapidly if birth rates decrease suddenly.

Page 8: Population demography and dynamics

Age Structure

• Cohort or group of individuals w/in the same age.• Population with large number of

young individual tends to grow rapidly.

Page 9: Population demography and dynamics

Age Structure Pyramid

Page 10: Population demography and dynamics

Life Tables• Contains –fate of a cohort from birth until

death–number of offspring produced–individuals that died each year– number of individuals that

survived

Page 11: Population demography and dynamics

Life Table

Page 12: Population demography and dynamics

Survival Curve• a graphic method that shows some

of the data in life table

• It shows– survivorship of a population–percentage of the original population

that survive to a given age.

Page 13: Population demography and dynamics
Page 14: Population demography and dynamics
Page 15: Population demography and dynamics

• Standardized Survival Schedule (lx)

• Age-Specific Survivorship (gx)

Survival Curve

Page 16: Population demography and dynamics

• Life Expectancy (ex)

Survival Curve

Page 17: Population demography and dynamics

Pambasag!

1. What is demography?

Page 18: Population demography and dynamics

Pambasag!

2. What are the four factors affecting population demography?

Page 19: Population demography and dynamics

Pambasag!

3. The shorter the ______ the higher the population growth rate.

Page 20: Population demography and dynamics

Pambasag!

4. It is a type of a life table which is commonly used for organisms that are difficult to classify by age and the ecological role defend more on their size or stage of development.

Page 21: Population demography and dynamics

Pambasag!

5. It is a curve used to demonstrate the survivorship of the organisms in a certain population.

Page 22: Population demography and dynamics

Pambasag!

6. A population with a large number of young individuals tends _______ in growth rate.

Page 23: Population demography and dynamics

Pambasag!

7. What is the most commonly effect to a population with a large ratio of female individuals?

Page 24: Population demography and dynamics

Pambasag!

8. Age structure is defined by ________ in each cohort.

Page 25: Population demography and dynamics

Pambasag!

9. The sudden change in demography and structure of a population.

Page 26: Population demography and dynamics

Pambasag!

10. What is the possible effect of the increase in generation time together with the increase in number of males in a population?

Page 27: Population demography and dynamics

Pambasag!

11-20. Show your solutions.Age (year/s) Number of living individuals

0 300

1 267

2 222

3 197

4 156

5 130

6 95

7 50

8 25

Page 28: Population demography and dynamics

References

• Campbell,Neil. Reece