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Specialist species
Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food. EX: Panda
Generalist species
species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions. EX: cockroaches, raccoon, rats, humans
Exponential growth
Population growth that grows slowly at first, then more and more rapidly. It has an abundance of resources for an ever-increasing population. (J-shaped curve)
Logistic growth
Population growth in which a population begins with a period of slow growth followed by a brief period of exponential growth before leveling off at a stable size (S-shaped curve)
K-selected species (K-strategists)
Species that tend to be large, have few offspring, invest lots of time and energy caring for offspring, take a long time to mature, and have long lifespans. (most mammals)
r-selected species (r-strategists)
Species that tend to be relatively small, have many offspring, invest minimal energy and time caring for offspring, mature early, have short lifespans. (most reptiles, amphibians, and insects)
Biotic potential (r) (intrinsic growth rate)
The maximum rate at which a population could increase under ideal conditions (like unlimited food and space)
carrying capacity (K)
The limit of number of individuals of a population that a environment can support (due to limited resources such as food, water, etc)
Overshoot
when a population becomes larger than the environment's carrying capacity
density dependent factors
factors whose effects on the population vary with the number of individuals in a given area EX: disease
density independent factors
limiting factor that affects all populations in similar ways, regardless of population size EX: natural disasters
survivorship curve type 1
low death rates during early and middle life and an increase in death rates among older age groups
survivorship curve type II
the death rate is constant over the organism's life span
survivorship curve type III
high death rates for the young, then a slower death rate for survivors
Population density
Number of individuals per unit area
crude birth rate (CBR)
the number of live births yearly per 1000 people in a population
crude death rate (CDR)
The number of deaths per year per 1,000 people in a population
Immigration
Movement of individuals into a population
Emmigration
movement of individuals out of a population
Developed country
a modern, industrialized country in which people are generally better educated and healthier and live longer than people in developing countries do
Developing country
A country that has low industrial production and little modern technology. Typically has low GDP & low standard of living
Infant Mortality Rate (IMR)
The total number of deaths in a year among infants under one year old for every 1,000 live births. This is higher in developing countries with less access to healthcare and clean water
Replacement level fertility
the number of children a couple must have to replace themselves (Roughly 2.1 in developed contries, but higher in developing countries)
Total fertility rate (TFR)
The average number of children a woman will have throughout her childbearing years.
population momentum
continued population growth after growth reduction measures have been implemented (the lag time between enacting birth control policies and the effects of those policies on population growth)
age structure diagram (population pyramid)
a graph that breaks down the divisions of age into cohorts and according to sex
cohort
A group of individuals of the same age.
per capita
per person
demographic transition
Movement of a population from a high birth rate, high death rate to a low birth rate, low death rate. This occurs as a country m oves from a subsitence economy to industrialization and increased affluence
family planning
the practice of regulating the number or spacing of offspring through the use of birth control
die-off/dieback
rapid population decline usually experienced after the overshoot of the carrying capacity
doubling time
The time required for a population to double in size. Calculated by 70/growth rate(r)
mortality
death rate
sex ratio
The ratio of males to females in a population. If skewed, it can slow population growth.
Rule of 70
Doubling time = 70/(percentage growth rate).
Population distribution
a description of how individuals are distributed with respect to one another (clumped, random, or uniform)
