Chapter 5 Flashcards
What is Population Biology?
the science of modeling changes in species abundance
What are the factors that control population?
Morality
Reproductive rates
Resources
Competition
Disease
Accident
What are ways species get onto the islands?
Walking
Flying
Hitchhiking
rafting
Ballooning
Drifting in air
Swimming and floating
What are factors for population founders to exist on the island’s resources?
Habitat must be available and suitable
Mates present
Food present
Nursery habitat presents
(There are unique species that would have been remarkable, but did not have the right resources)
Predator?
Competitors?
Disease?
All individuals alive today are part of a continuum of success since the dawn of life!
What is the equation for N (Population size)?
N (population size) = Increase population size (birth + immigration) - decrease population size (death - emigration)
What are the changes of population for basic models of population growth under “closed” population (no immigration and emigration)?
Birth rate > death rate, N increases
Birth rate < death rate, N decreases
Birth rate = death rate, N stays the same
Many populations can be modeled by a ____________.
Sigmoid curve
What are the three phases of population growth?
Lag phase
- Slow (but positive_ growth at low N
- B > D
Exponential phase
- Population increases rapidly over short time steps as N gets larger
- B > D
Stationary Phase
- Population reaches the carrying capacity (K)
- B = D
What is carrying capacity?
Known as K
maximum number of individuals an environment can support
What is biotic potential?
The ability for a species to increase its population size if all offspring survive to reproduce in their parents’ turn
- Species that have high fecundity will have greater biotic potential than species with low fecundity
maximum reproductive rate of an organism, given unlimited resources and ideal environmental conditions
What is exponential growth rate?
a population can only grow at an exponential rate this fast if nothing limits its growth
What is fecundity?
high reproductive output
What is doubling time?
the time required for a population to double in number
- Larger populations will have generally have shorter doubling times than smaller population
Islands connected to a continent became populated by ___________________ that could fly, float, or hitchhike across the ocean barrier.
indigenous species
Species migration includes not only the travel to the island, but also…..
successful establishment of a population.
Population on islands are founded when…..
1+ individuals capable of reproducing establish successfully.