 a. When individuals produce more offspring at a time  B. Reproduce more often  C. Reproduce earlier in life  Reproducing earlier in life has greatest effect

 Smaller organisms like bacteria and insects usually have shorter generation times and can reproduce when they are only a few hours or days old.  As a result: These populations grow more quickly!  Larger organisms take longer to sexually mature and have a lower reproductive potential.

 Grow faster and faster  Large number of individuals are added to the population in each succeeding time period  For this to occur must have plenty of food, space, no competition/predators  “J” shaped curve

 IF ONE DOG HAS 6 PUPPIES: EACH PAIR OF DOGS IN THAT GENERATION HAS 6 PUPPIES THERE WILL BE 18 DOGS IN THE NEXT GENERATION. IF EACH OF THOSE 18 PUPPIES MATES AND HAS 6 PUPPIES, THE NEXT GENERATION WILL HAVE 54 DOGS, AND SO ON………………….

 Natural conditions not ideal or constant  Rarely grow at reproductive potential  Eventually reach Carrying Capacity  Resource Limits  Competition Within a Population

 Maximum population that the ecosystem can support indefinitely May increase beyond but cannot stay at that size Ex. Rabbits May be briefly exceeded But not sustained

 A. Originally no rabbits in Australia, introduced in 1859  B. Numbers increased rapidly  C. No predators, no competition, plenty of food (vegetation)  D. Eventually, disease and starvation caused crash  E. Over time, vegetation recovered  F. Rabbits increased again  G. Continued increases and decreases, but less dramatically

 Competition occurs in populations when members use the same resource in the same way  As fewer resources become available, competition among individuals increases and the population reaches carrying capacity.  Population density = number of individuals per unit area

 Population is limited dependent on the size of the population.  Characteristics: A. Death occurs more quickly in crowded populations B. Densely packed together C. Rapid growth Examples: limited resources, disease, predation

 Certain percentage of population dies regardless of population’s density.  Examples: Severe weather Natural disasters

 The unique ROLE of a species in an ecosystem.  It is NOT a PLACE (that would be a habitat)  An organism’s niche includes: A. Physical home B. Environmental factors necessary for survival C. All interactions with other organisms