3.0 Unit 3 Overview: Populations

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• What are the major characteristics of populations? 
• How do populations react to environmental conditions changing? 
• What are the differences in species’ reproductive patterns? 
• How can a population change be calculated using a formula? 

⚡ Key Terms 

3.1 Generalist and Specialist Species 

• Generalist Species 
• Specialist species 

3.2 K Selected and r selected species 

• K selected species 
• R selected species 
• Biotic potential 

3.3  Survivorship curves 

• Survivorship curve

3.4 Carrying Capacity

• Carrying Capacity 
• Population Overshoot  
• Environmental resistance 

3.5 Population Growth and Resource Availability 

• Population Growth 
• Logistic growth 
• Exponential growth 

3.6 Age Structure Diagrams 

• Age structure diagram 
• Top heavy age structure 
• Stationary age structure diagram 
• Inverted pyramid age structure diagram 
• Constrictive age structure diagram 
• Expansive pyramid age structure diagram 

3.7 Total fertility rate 

• Total fertility rate 
• Crude Birth rate 
• Crude death rate 
• Family planning 
• Infant mortality rate 
• Life expectancy 
• Replacement level fertility 

3.8 Human Population Dynamics 

• Population density 
• Immigration and Emigration 

• Density dependent factor 
• Density independent factor 
• Rule of 70 

3.9 Demographic Transition 

• Demographic Transition 
• Pre industrial demographic transition 
• Transitional demographic transition 
• Industrial demographic transition
• Post Industrial demographic transition

⚡ Quick Study - Key Terms 

• Age structure diagrams: An age structure diagram shows the distribution of population for a country. If a population is stable then there will be an equal distribution amongst the age groups. If a population is predicted to decline then there will be a large group of elders. 

• Biotic potential ➪ Refers to the maximum reproductive rate of a population in ideal conditions 
  • how many times an organism can reproduce 
  • r is much higher than K 
  • exponential growth without limited

• Carrying capacity ➪  The maximum population size of the species that the environment can sustain, given the food, habitat, water and other necessities available in the environment  
• Density-dependent Factors ➪  The size of the population will affect survival ➪ access to clean water and air, food availability ,disease, territory size  
• Density-independent Factors ➪ Affect population regardless of population density (size) ➪ weather, climate, storms fires, heatwaves, droughts 
• Survivorship curve ➪  A line that displays the relative survival rates of a cohort - a group of individuals of the same age- in a population, from birth to the maximum age reached by any one cohort member. Type 1,2,3 curves 
• The Rule of 70 ➪ The rule of 70 states that dividing the number of 70 by the percentage population growth rate approximates the populations doubling it