Esa Unit3

Population

• Geographic Distribution

• Density

• Growth Rate

Geographic Distribution

Population Density

Population Density

Plant Broadcasting

Dandelion

Biogeography

• Geographical Distribution of Species

• Endemic species

Range Expansion

• Africanized bees

Range Expansion

• West Nile encephalitis virus

Species Transplants

• European Starling, 1890

FRANKLIN, N.J. —  The black carcasses of dead starlings still pepper the snowy roads and lawns of central New Jersey’s rural Griggstown community three days after federal officials used a pesticide to kill as many as 5,000 of the birds.Many residents Monday were still getting over their shock from the sudden spate of deaths. Some were unaware that the deaths resulted from an intentional culling and that the pesticide used was harmless to people and pets.“It was raining birds,” said Franklin Township Mayor Brian Levine. “It got people a little anxious.”The U.S. Department of Agriculture called local police last week and the Somerset County Health Department to warn them that a culling program was under way, but there was no notice that dead birds could fall from the sky, Levine said.“A lot of us are concerned because it’s so odd,” said Chris Jiamboi, 49, as his vehicle idled along a stretch of road in Griggstown marked with the flattened remains of dead starlings. “There were a lot of them dead in the roads and no one drives fast enough around here to kill a bird. Then they started showing up dead in people’s backyards.”

Resource Partitioning

Character Displacement

Population Change

Factors: BirthsDeaths

Migration Flux

Arithmetic vs. Exponential

Bacterial Growth

Bacterial Growth Curve

Reproductive Rates

• Breeding Age

• Litter Size

• Gestation Period

• Longevity

• Gender Ratio/Mating System

Mating Schemes

• PolyandrousAfrican hunting dogs

• Polygynous

Courtship

Growth StrategiesR-select K-selectShort life Long life

Rapid GrowthMany small offspringLittle parental investmentPopulation fluctuationUsually preyEnvironmentally adaptable

Slower growthFewer, larger offspringHigher parental carePopulation size stablePredator or highly competitiveAdapted to stable environment

Limits to Growth

In Real Life . . .

Population Cycles

Isle Royale

Human Population

Since 1800

Malthus1797: Essay on Population

As population rises . . . . .

Labor Glut ----> Unemployment

Prices Rise ------> Hunger, Food Shortages

Voluntary Limit on Families

Falling Birth Rates

Drop in Death Rate

Due to:

Vaccines

Antibiotics

Better diet

Lifestyle choices

Safety considerations

Population Dynamics• Growth Rate = Birth Rate – Death Rate

% x/1000 – y/1000

• For example,

Birth Rate = 43/1000, Death Rate = 11/1000Growth Rate = 32/1000 = 3.2/100 = 3.2 %

World Population

• http://www.ibiblio.org/lunarbin/worldpop

• 7 Billion in April 2010???

Doubling Time

• Amount of timeelapsed until the population will have doubled

National Growth Rates

Population Profiles

Demographic Transition

US population

US population

Distribution

One Child One Family

India

Sustainability

• Issues– Resources: Food, water, air, energy

– Waste treatment

– Space allocation

– Standard of living