Human population

Factors influencing
pop.size

density dependent factors:
food, water, shelter

density independent factors:
fire, floods, climatic events

Growth Rate

Sex Ratio

Age Structure

Growth Rate

Growth Models

Exponential Growth Rate

Logistic Growth Rate

Pop. Dynamics

r

Humans are not unique in their ability to alter their environment. The ability ro alter their environment to increase its carrying capacity, sometimes to the detriment of other species.Long-term exponential growth carries with it the potential risk of famine, disease, and large-scale death, as well as social consequences of crowding such as increased crime.

Survivorship curve
(as a function of age)

Type 1: live a long time
die of old age(human)

Type 2: does not really depend on age
(birds)

Type 3: lots of young die
(trees)

Rule of 70

r

finding the doubling time of a pop.doubling time (in years)= 70/growth rate

Pop. Control

China: one child policy

India: education of demals
access to family planning

Increased affluence=increased
environmental challenges