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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