Population

Growth Rate Formula

(BR-DR) + (I-e)/total pop

Life in US has changed...

-Increased life expectancy -Increased women working outside home -Increased indoor pluming -Increased minimum wage -Increased homicides

List 3 factors that affect birth or death rates. Will they cause birth rates or death rates to increase/decrease?

1) Health care (low=high birth and death rates, high=low birth and death rates) 2) Women's education (low=high birth rate, high=low birth rate) 3) Access to food (low=high death rate, high=low death rate)

Explain the 3 types of Population Distribution.

1) Random: if the position of each individual is independent of others (ex: SPIDERS, clams) 2) Uniform: resource availability, intraspecific competition (ex: compete for H2O, autotoxicity), TREES 3) Clumped: individuals clustered together (habitat differences, seasonal changes in weather, reproductive patterns, social behavior), MAMMALS

3 most populous countries now

1. China 2. India 3. USA

3 most populous countries in 50 years

1. India 2. China 3. Pakistan

Current US population

320 million

Current world population

7 billion

Doubling Time Formula

70/GR%

Plant Parasites

A plant that depends on host plant for nutrition and cannot photosynthesize (cancer root) or entirely parasitic (mistletoe)

Exploitation

A relationship between to organisms in which one benefits and the other is killed (ex: predation, herbivory, parasitism)

Commensalism

A relationship between two organisms in which one organism benefits and the other is unaffected (ex: clownfish and anemone)

Parasitism

A relationship between two organisms of different species where one benefits and the other is harmed

Mutualism

A relationship between two species in which both species benefit (ex: buffalo and oxpecker)

What typically happens to birth rates when a family moves from a rural to urban setting?

Birth rates drop because the cost of living is way more expensive and the parents are typically too busy (usually working) to start a family.

Define the term carrying capacity.

Carrying capacity is the maximum number of individuals that a habitat can sustain for a long period of time.

Identify characteristics of the above countries based upon the age structre diagrams.

Country X population is increasing rapidly. Life expectancy is relatively low, while total fertility rate for females is high. This is a developing country. Population momentum will cause this country to continue its growth for several years even if fertility rate drops. Country Y population is stable. Life expectancy is high, while total fertility rate for females is low. This country is close to the magical 2 child number per family. This is a developed country. Country Z population is increasing but is on its way to becoming stable. Fertility rate is dropping while life expectancy is increasing. This country is transitioning to a developed country.

Give an example of a density dependent and density independent factor.

Dependent: Disease spreads more with a higher population and not as much with a smaller one. (food, shelter, parasites, predators) Independent: Catastrophic events are not affected by population size.

If a population that has been growing rapidly suddenly drops their fertility rate to replacement level, what would you expect to see in the future generations? What is this called?

Future generations: population momentum

Give two examples of how carrying capacity can impose limits on a population. What are some factors that will limit population growth?

If a population exceeds the carrying capacity there are not enough resources (nutrients, light, dissolved oxygen, water) and there will be a die off of individuals until the population dips below the carrying capacity. If the population is lower than the carrying capacity then the population will increase. Factors that will limit population growth physical abiotic factors (temperature, nutrients, amount of light, dissolved oxygen, pH) and biotic factors (parasites, predators, competitors)

Describe two ways human activity can raise a habitats carrying capacity for humans.

Irrigation to deliver water to grow more crops. Fertilizers and pesticides to increase crop yield. Turning the natural biome into farmland to grow more crops. Medicines to kill parasites.

What happens to fertility in a country as you progress through the demographic transition stages?

It slowly declines then plummets to zero.

Explain the role of keystone species in ecosystems. Give examples.

Keystone species play a role in its community that is far more important than its relative abundance might suggest. Loss of a keystone species would have a large detrimental effect on the ENTIRE community. They are called "keystone" species because they hold together then community they live in and if they are removed, then the entire community will collapse. Examples of these species include starfish, beavers, sea otters, and any other apex predators.

Why might it be easier to to reduce birth rates than to raise them?

More expensive, quality of life is lower, no free time (lifestyle change)

Urbanization

Movement of people from rural areas to cities -smaller families than rural (cost of living)

Explain how a population's consumption of natural resources might be controlled. Give two examples of how nature slows down the consumption of natural resoures by a population.

One example of how nature controls consumption is between two populations for the same habitat. If two populations of predators are competing for the same prey, eventually their will not be enought prey to support both populations of predator and one of the populations would die out, leave the area, or switch to another food source. Examples include eagles and falcons competing for mice and fish, cheetahs and lions competing for grazing animals, or 2 species of birds competing for insects. Humans can find alternative energy sources.

Explain what will happen to a country as it progresses through the demographic transition model

Preindustrial Slow population growth because birth rate and death rate are both high. Harsh living condition, poor medicinal care. Transitional Birth rates are high, but due to better food, water, and medicinal care death rates are lower. This causes rapid population growth. Birth rates remain high due to cultural or religous traditions and lack of education for women. Industrial Population growth is still high, but birth rate drops close to death rate. Most developed countries are in this phase. Postindustrial Population approaches and reaches zero growth rate. Population may drop below zero growth rate and start declining in population *TOTAL FERTILITY RATE WILL DECREASE ***MAJORITY OF GROWTH HAPPENS WHEN DEATH RATE DROPS BUT BIRTH RATE REMAINS HIGH

Explain the differences between Primary and Secondary Succession

Primary: colonization of a region where there is no pre-existing community (after volcanic eruption--no soil) Secondary: colonization where therer was an existing community that was cleared by a disturbance (forest fire--soil with nutrients, seeds, root structure)

As a population grows, what impact would you expect to see upon the environment?

There would be a strain on food sources, expecially for the herbivores. Plants wouldn't be able to reproduce fast enough, so they would decrease as the herbivores eat all of them. Without any food, the herbivores would die-off, causing the rest of the food chain to be without food and die-off as well.

r-selected species

a species that has a high intrinsic growth rate, which often leads to population overshoots and die-offs; opportunists (ex: bacteria, rodents, insects)

K-selected species

a species with a low intrinsic growth rate that causes the population to increase slowly until it reaches carrying capacity (ex: mammals)

Factors affecting fertility

changes in women's roles; national & international population control efforts; increasing age of 1st marriage; access to women's education; quality of health care

population momentum

continued growth of a population even after replacement level fertility

Poverty can affect population in all of the following ways EXCEPT

decreasing total fertility (no access or education to birth control)

Cairo Conference 1994

developed ideas to push out to world -universal access to family-planning -improve health care of infants, children, and mothers -improve women's and girls' education -increase men's involvement in child-rearing responsibilities -eradicate poverty

A country with a large population that is relatively affluent and is technologically advanced will

have a low emigration rate

What are the two reasons for the rapid growth of the human population over the past 8,000 years?

increased medical and technolgical advances

The maximum rate at which a population increases is known as its

intrinsic growth rate

Indicators of good nation

life expectancy and infant mortality rate

Growing developing nations

lots of resource use because they are trying to increase standard of living

What levels of complexity make up the biosphere? (smallest to largest)

organism, population, community, ecosystem, biome, biosphere

Endoparasite

parasite living on the inside of its host (ex: tapeworm)

Ectoparasites

parasites that live on the external surface of a host (ex: lice, fleas, ticks)

China's One Child Policy

penalized couples with more than one or two children by: -raising taxes -charging other fees -eliminating income tax deductions -loss of health care benefits, free education, food allotments, and job options For having one child: -paid leave to women for fertility operations -monthly subsidy -job priorities -additional food -housing preferences Consequences: -gender imbalance -increase in orphans -punishments **SUCCESSFUL IN CUTTING POPULATION GROWTH

GDP

potential economic success of a country (the higher the better)

Replacement level fertility

the total fertility rate required to offset the average number of deaths in a population in order to maintain the current population size (2 kids/family)