1. Population
    a group of organisms that belong to the same species and live in a particular space
  2. Size estimation
    by sampling a small area and multiplying by the whole
  3. Density
    • How crowded it is
    • *individuals/ km^2
    • Japan- high density
  4. Dispersion
    Spatial distribution
  5. Clumped
    • groups are clustered due to:
    • food, living spaces
  6. Uniform
    consistent space between each organism
  7. random
    no real pattern
  8. United States
    • Birth rate: 4 million/year
    • Death Rate: 2.6 million/year
    • Life expectancy: male-24 years, female- 80 years
  9. Age structure of a country
    High % of young people= high potential for growth (vise versa)
  10. Survivor ship
    3 types of curves
    • Type 1- small chance of dying until very old- human, elephants
    • type 2- equal chance of dying at any time in life- robins, sparrow
    • type 3- good chance of dying young, but live long if make it- salmon
  11. Add to a population
    Birth and immigartion
  12. Subtract from a population
    Death and emigration
  13. Exponential model of population growth
    • population grows slowly at first then pop. will add a larger # of individuals with each generation
    • It is realistic
    • Because only under certain conditions and for limited periods of time
  14. The Logistic model
    accounts for the influence of limiting factors
  15. carrying capacity
    • # of individuals the enviornment can support over a long period of time
    • Death rate= birth rate when pop. size is at carying capacity
    • fluctuates with number of prey- predators
  16. Density Independent Limiting Factors
    weather, flood, fire
  17. Density Dependent Limiting Factors
    shortages of food, shortages of nesting sites
  18. Population Fluctuations
    • all populations fluctuate in size
    • ex. lynx and snowshoe hare
  19. Small Populations
    vulnerable to extinction, increased liklihood of imbreeding, decrease in genetic variation
  20. Original human population
    small nomadic groups, hunter gatherer lifestyle, low growth rate, high mortality rate
  21. Agriculture Revolution
    (10,000- 20,000 years ago)
    • domesticated animals, cultivated plants
    • result: stabilized food supplies, human population grew
  22. Population Explosion
    • After 1650
    • better sanitation
    • control of disease
    • more food
    • drop in growth rate can be decieving because it doesnt mean the population will stop growing
  23. Developed Country
    better educated, healthier, live longer
  24. Developing Countries
    poorer, populations growing faster
  25. predator
    • eats all parts of another species
    • adaptations: sticky web, flesh cutting teeth, speed
  26. prey
    adaptations: deceptive markings, chemical defenses, mimicry
  27. herbavores
    form of predation
    adaptations: same as predator
  28. Batesian mimicry
    harmless animal trying to look like harmful one
  29. Mullerian mimicry
    when two or more dangerous or distasteful species look alike
  30. plants
    adaptations: sharp thorns, spines, sticky hairs, tough leaves
  31. Secondary compounds
    • chemical defenses of plants (poisonous, irritating)
    • ex, strychnine, nicotine
  32. interspecific competition
    2 species struggle for same limited resource
  33. Competitive Exclusion
    one species eliminated from a community because competition for same limited resource
  34. character displacement
    • evolution of differences in characteristics due to competition
    • ex. beaks of galapagos finches
  35. resource partitioning
    • species avoid competition by dividing up the resource
    • ex. 5 species of warbler divide up diff. parts of tree
  36. symbiosis
    close long term relationship between two organisms
  37. Parasitism
    the parasite benefits and host is harmed
  38. ectoparasite
    • outside
    • ex. aphid, lice, ticks, mosquitoes, leeches
  39. endoparasite
    • inside
    • ex. tapeworm, heartworm
  40. mutualism
    • both species benefit
    • ex. ants and acacia tree
  41. commensialism
    • one species benefits, other is not affected
    • ex. cape buffalo and cattle egret
  42. ecological succession
    gradual, sequantial regrowth of a species in an area
  43. pioneer species
    • species of organisms that predominate early in succesion
    • characteristics: small, grow quickly, reproduce quickly
  44. climax community
    • community that reached a stable end point
    • stability does not last forever
Card Set
chapter 19 and 20