APES Semester 1 in review

2014, The year everyone gets a 5!

Who Lives Where and Why?

Evolutionary response…

Resource Partitioning - Whenever there is competition for the same

resources, someone loses out!

Evolution

Speciation (Galapagos Finches)

Geological Context (space and time for evolution)

• Plate tectonics

• Geological time scale (fig. 5-21)

• Cambrian explosion

• Selective breeding• Artificial selection• Natural selection

Island biogeography…. Founder effec

The Green Revolution• To eliminate hunger by improving crop performance• Movement to increase yields by using:

– New crop cultivars– Irrigation– Fertilizers– Pesticides– Mechanization

Results:• Did not eliminate famine• Population still increasing• Increase cost of production• An increased negative environmental impact• Didn’t work for everyone

Coal-several (400) hundred years

Oil- Peak Oil passed

Natural Gas – at least a 50 year supply in the United States

Chapter 13: Fossil FuelsExxon Valdez, Drilling in ANWR

More Energy Facts

• We get 50% of our crude oil from foreign sources

• Alaska pipeline built to help increase production of domestic crude oil

• Types of coal:• Peat (not coal) Lignite (brown coal)

Bituminous coal (soft coal with high sulfur)

Anthracite (hard coal with low sulfur)

K- Selected Species populations of a roughly constant size have low reproductive rates. offspring require extensive postnatal care until they have sufficiently matured. They are very limited in resourses therefore they are a very competitive species.

Elephants, Rhinos and long lived plants are examples of a k-selected species.

R-Selected Species populations that experience rapid growth of the J-curve variety. offspring produced are numerous, mature quite rapidly, and require very little postnatal care. this population grows fast, reproduces quickly, and dies quickly.

Bacteria and mice are examples of r- selected species.

exponential

r-species

K-species

--------------------------------------------------Carrying Capacity-

Carrying capacity changes…

exponential

r-species

K-species

--------------------------------------------------Carrying Capacity

Chapter 6•World population trends•Calculations •Demographic transition•Age structure diagrams•Developed vs. developing countries

Chapter 7

•Fertility rates•World bank•1994 UN conference in Cairo- program of action

Ch 6 and 7: The Human Population

Population DensityPopulation Density

• Population Density (or ecological population density) is the amount of individuals in a population per unit habitat area– Some species exist in high densities - Mice– Some species exist in low densities - Mountain

lions

• Density depends upon– social/population structure– mating relationships– time of year

Population DispersionPopulation DispersionPopulation dispersion is the spatial pattern of distribution

There are three main classifications

Clumped: individuals are lumped into groups ex. Flocking birds or herbivore herds due to resources that are clumped or social interactions most common http://www.johndarm.clara.net/galleryphots/

Population Population DispersionDispersion

Uniform: Individuals are regularly spaced in the environment - ex. Creosote bush due to antagonism between individuals, or do to regular spacing of resources rare because resources are rarely evenly spaced

http://www.calflora.net/bloomingplants/creosotebush2.html

www.agry.purdue.edu/turf/ tips/2002/clover611.htm

Random: Individuals are randomly dispersed in the environment ex. Dandelions due to random distribution of resources in the environment, and neither positive nor negative interaction between individuals rare because these conditions are rarely met

Age StructureAge Structure• The age structure of a population is

usually shown graphically

• The population is usually divided up into prereproductives, reproductives and postreproductives

• The age structure of a population dictates whether is will grow, shrink, or stay the same size

Age Structure DiagramsAge Structure DiagramsPositive Growth Zero Growth Negative Growth (ZPG)Pyramid Shape Vertical Edges Inverted Pyramid

Population Dynamics Population Dynamics OutlineOutline

• Characteristics of a Population

• Population Dynamics and Population Dynamics and Carrying CapacityCarrying Capacity

• Reproductive Strategies

• Conservation Biology

• Human Impacts

• Working with Nature

• Biotic Potential–factors allow a population to increase

under ideal conditions, potentially leading to exponential growth

• Environmental Resistance –affect the young more than the

elderly in a population, thereby affecting recruitment (survival to reproductive age)

(b) crude birth rate= number birth per 1000 individuals(d) crude death rate= number death per 1000 individuals(r) growth rate = natural increase in population expressed as percent

per years (If this number is negative, the population is shrinking.) equation:

rate = birth – death

But other factors affect population growth in a certain area…

Population growth rates

increase population decrease population births deathsimmigration emigration (exit)

r = (birth - death)+ (immigration-emigration)

immigration = migration of individuals into a population from another area or country

emigration = migration of individuals from a population bound for another country

r = (birth - death)+ (immigration-emigration)

B D I E r=( 10/1000) – (5/1000) + (1/1000) – (10/1000) r=(0.01-0.005) + (0.001 – 0.01)r = 0.005 – 0.009 = -0.004 or –0.4% per year

example: population of 10,000 has 100 births (10 per 1000)50 deaths (5 per 1000)10 immigration (1 per 1000)100 emigration (10 per 1000)

You try.

Know Rule of 70

If the growth rate is 1% and the population size is 10,000, how many years will it take to get to a population of 40,000?

Population doubling:

In 140 years, the population will be 40,000 people.SHOW YOUR WORK!!!!!!!!!

(70 years)(2) =140 years 

2 D.T. 40,000

1 D.T. 20,000

In 70 years the population will be 20,00070/rate =70/1% =70 years to double

Bottom Line= as countries develop, first their death rate drops and then their birth rate drops

Reasons for the phases:

Phase II: medical care

nutrition (births still high)

technology

Phase III: birth control

education (of women)

lower mortality rate of infants

less child labor

Developed Countries Canada, U.S., Australia, Western Europe

(Denmark)

Developing Countries Latin America, China, Africa (Kenya)

1/5 of the world’s pop. Lives in absolute poverty, illiterate, lack clean H2O and don’t have enough food

80% of world’s pop. Lives in developing co. and growing

• Total fertility= avg. # of children born per woman

• For developed countries = 2.1• For developing countries = 2.6• Fertility of 2.0= replacement level

– Under 2.0 = shrinking population– Over 2.0 = growing pop.

• For developed countries = 2.1• For developing countries = 2.6(or higher)

• Special agency of the United Nations

• Receives $$ from developed co. and loans $$ to developing co.

– Sometimes this backfires by increasing debt

• Oversees all types of issues, not just environmental issues

– Ex. electricity, roads, new modern technology

Toxicology

• Extrapolation from animal to human• Usually physiology of other mammals is like

humans, so rats, mice, dogs, cats, etc. make good surrogates.

• But, CATS CAN NOT take Tylenol, Aspirin;• DOGS can not take chocolate.

• Then, what can experimental animals tolerate that humans can't ??

17 June 2010 EnvHealth&Tox.ppt 33

Toxicology

• Expense of laboratory studies– Drug approval by Food & Drug

Administration (FDA) takes years, $$.• Safety of medicines

• Effectiveness of medicines

– Studies of environmental chemicals, biological agents also takes time & money.

17 June 2010 EnvHealth&Tox.ppt 34

Toxicology

17 June 2010 EnvHealth&Tox.ppt 35

•Other factors:–Bioaccumulation: increased concentration in specific tissues over time.–Biomagnification: increased concentration up a food web.

Dose mg/kg (ppm)

Threshold Level

50 %

0.0001 0.001 0.1 1.0

Method:

Measure chemical’s median lethal dose (LD50); the amount received in one dose that kills 50% of the organisms (usually rats or mice) in a test population within a 14 day period.

How Much Exposure to a Particular Toxic Chemical Causes a Harmful Response?

Biomagnification Biomagnification-

the increase in a chemical concentration in animal tissues as the chemical moves up the food chain.

Persistence Persistence- how long a chemical remains in

the environment

Risk Analysis