population clock
TRANSCRIPT
Population ClockPopulation Clockhttp://www.poodwaddle.com/clocks/worldclock/
The Water Lily StoryThe Water Lily StoryThe Anchor Bay High School pond has one water lily leaf floating on the surface. The lily population will double in size every day if left unchecked. The water lilies will smother the pond in 30 days, effectively killing all other living things in the water.
At what point should you concern yourself with cutting back the lily plants? When the pond is 1/8th covered, one-fourth covered, or one-half covered?
Characteristics of PopulationsCharacteristics of Populations Geographic Geographic
DistributionDistribution
DensityDensity
Growth rateGrowth rate
Age structureAge structure
Area inhabited by a Area inhabited by a populationpopulation
The # of individuals The # of individuals per unit areaper unit area
Rate at which a Rate at which a population changes population changes sizesize
Different ages of the Different ages of the organisms in a organisms in a populationpopulation
Population DensityPopulation Density The number of individuals per unit areaThe number of individuals per unit area
Population GrowthPopulation GrowthFactors that affect population size:Factors that affect population size: Birth RateBirth Rate
Death RateDeath Rate
ImmigrationImmigration
EmigrationEmigration
• the amount of births the amount of births
• the amount of deathsthe amount of deaths
• moving into an areamoving into an area
• moving out of an areamoving out of an area
How is the Population Affected?How is the Population Affected?Increase or DecreaseIncrease or Decrease
birth rate & birth rate & death rate death rate
birth rate & birth rate & death rate death rate
immigrants & immigrants & emigrants emigrants
immigrants & immigrants & emigrants emigrants
DecreaseDecrease
IncreaseIncrease
DecreaseDecrease
IncreaseIncrease
Exponential GrowthExponential Growth Will occur under IDEAL Will occur under IDEAL
conditionsconditions1.1. unlimited resourcesunlimited resources2.2. no predatorsno predators3.3. no diseaseno disease4.4. plenty of spaceplenty of space
Produces a J – shaped CurveProduces a J – shaped Curve
Logistic CurveLogistic CurveS- CurveS- Curve
In ecosystems:In ecosystems:• Resources are limitedResources are limited• PredatorsPredators• DiseaseDisease
The growth of populations slows or stops The growth of populations slows or stops (actually averages out to a steady size)(actually averages out to a steady size)
• Birth rate = death rateBirth rate = death rate• Immigration = emigrationImmigration = emigration
Leveled-off population reached its Leveled-off population reached its carrying capacitycarrying capacity
Carrying CapacityCarrying Capacity The largest number of organisms The largest number of organisms
that a given ecosystem can supportthat a given ecosystem can support