Populaiton growth and carrying capacity cer
carrying capacity and population growth with claims, evidence and reasoning
Published on: Mar 4, 2016
Transcripts - Populaiton growth and carrying capacity cer
Do Now• Define the different types of symbiosis and give anexample– Commensalism –• Example:– Mutualism –• Example:– Parasitism –• Example:
Do Now• Define the different types of symbiosis and give an example– Commensalism – a relationship in which one organism benefits andthe other is not affected• Example: Barnacles on a whale– Mutualism – a relationship in which both organisms benefit fromeach other• Example: Birds eating pest off a rhino’s back– Parasitism – A relationship in which one organism benefits and theother is harmed• Example: Ticks on a dog
Population Growth andCarrying Capacity
Principles of Population Growth• Population is a group of organisms, all ofthe samespecies, that live in a specificareaat the same time.• Population growth is defined as anincrease in size of a population over time…• However, populations growat different rates.
Linear Growth• If a population grew at a set amount eachyear, say by 10 organisms per year, then thepopulation has LINEAR GROWTH• However, populations normally do not havelinear growth. Linear growth looks like this(Please draw in your notes)
Question• Your parents give you two options for allowance1. 1,000 a month2. A penny on the first day of the month thatdoubles to two pennies on the second dayand so on until the last dayof the month• Which option do you choose?
.01 .02 .04 .08 .16 .32.64 1.28 2.56 5.12 10.24 20.48 40.9681.92 163.84 327.68 655.36 1310.72 2621.44 5242.8810,485.76 209711.52 41943.04 83886.08 167772.16 335544.32 671088.641342177.282684354.565368709.1210,737,418.24Over 10 million!!On 31 day months
Exponential Growth• If you graph the allowance we just saw on thegraph it will look like this: (Please draw in yournotes)02000400060008000100001200014000160001 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Exponential Growth• A population that is growing without any limits,would have exponential growth.• Meaning that as the population gets bigger, it alsowill grow faster• But, populations cannot keep exponential growthfor very long, because the environment wouldnot be able to support it.
Carrying Capacity• The environment has a CARRYINGCAPACITY for each population…• Maximum # of organisms in a populationsupported by an ecosystem’sresources/limiting factors– Effected by factors such as the amount of:• Food, water, space, etc…– Can change when these factors change• EX: more food = higher carrying capacity!
Limiting Factors• Definition?Any biotic or abiotic factor thatcauses population size todecrease and influences whatcan live where
Question• What are some examples of things that canlimit growth?
Question• What are some examples of things that canlimit growth?– Food, space, ability to reporduce
What can limit growth?• Limiting factors limit growth• Different sizes of populations will alsohave different factors affecting them.• When growth has been limited itsgraph will look like this:(please draw in your notes)02004006008001000120014001 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Claim• Human beings have exceeded their carrycapacity on Earth
Reasoning• What will cause the human population to godown?
Reasoning• What will cause the human population to godown?– Disease– Starvation– Weather events (hurricanes, tornados, globalwarming)– War/Crime– Lack of fresh water– Pollution
QUESTION: Interpreting Graphs andDataWhat happensduring the“transitionalstage”?a. Birth rates rise; death rates drop; population increasesb. Birth rates drop; death rates drop; population decreasesc. Death rates drop; birth rates are stable; populationincreasesFigure 7.18
QUESTION: ViewpointsDo you believe that national governments shouldimplement policies, subsidies, or other programs toreduce birth rates?a. No, not at allb. Yes, but only positive incentives for fewer childrenc. Yes—penalties for too many childrend. Yes, both incentives and penalties
Exit Ticket• What is population growth?• Describe the the difference between linearand exponential growth?• What is a carrying capacity?• Name 3 reasons that the human populationmay decline?
Centers• Bill Nye Center• Population Growth Center• Otter Game – Counts as 2 centers