Download - STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

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Page 1: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

STAGES OF POPULATION GROWTH

Page 2: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

Population Growth can be…

• Exponential ORLimited(J curve) (S curve)

Page 3: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

STAGES OF POPULATION GROWTH

1) Lag Phase 2) Log Phase3) Stationary Phase 4) Decline/Death

Phase

Page 4: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

POPULATION GROWTH STAGES

• 1) LAG PHASE– Only a small

number of organisms are sexually mature and able to reproduce

– The organisms may be adjusting to their environment

Page 5: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

POPULATION GROWTH STAGES

• 2) LOG PHASE

– Exponential or Logarithmic acceleration

– Many organisms have reached sexual maturity

– They are able to reproduce

– The organisms have adjusted to the conditions around them (able to get food, shelter, water, etc for survival)

Page 6: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

POPULATION GROWTH STAGES

3) STATIONARY PHASE– Growth ceases (slows

down) and population remains relatively fixed in size

– The carrying capacity is reached

– The number of births and deaths balance each other out

– The immigration and emigration rate are roughly the same

Page 7: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)
Page 8: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

POPULATION GROWTH STAGES

• 4) DECLINE/DEATH PHASE– Population dies off–May return to lag

phase and the cycle may repeat

Page 9: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

PREDATOR PREY CURVES

Page 10: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

PREDATOR PREY CURVES

Page 11: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

PREDATOR/ PREY CURVES

• Show the rise and fall of predator and prey populations

• Developed by Italian mathematician Volterra from watching the rise and fall of Adriatic fishing fleets.

• Shows peaks and valleys when population levels rise and fall in response to the predator-prey feeding relationship

Page 12: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

PREDATOR/ PREY CURVES

• theory suggest that…• when prey are numerous their

predators increase in numbers• This reduces the prey population,

which in turn causes predator number to decline.

• The prey population eventually

recovers, starting a new cycle.

Page 13: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

HARE = prey, LYNX = predator

Page 14: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

YOUR TURN… Using the values on this graph, write 5

sentences to explain what is happening…

Page 15: STAGES OF POPULATION GROWTH. Population Growth can be… Exponential ORLimited (J curve)(S curve)

Credits

• Mrs K Casha