FOURTEEN

Vocabulary flashcards covering ecological patterns of population growth, mathematical variables, and species examples from the Channel Lakes study.

Channel Lakes study

A six-year study conducted in New York State across 22 locations that examined the population abundances and growth patterns of 23 insect species inhabiting goldenrod inflorescences under similar environmental conditions.

Lace bug (Family Tingidae)

The most abundant insect species identified in the Channel Lakes study; despite having a median maximum abundance of less than one individual per 10 stems, localized extreme spikes drove it to the highest overall abundance.

Golden rod leaf beetle

The second most common insect species in the Channel Lakes study, exhibiting a median maximum abundance positioned squarely in the middle of a predictable, normal distribution.

Membracid

An insect species in the Channel Lakes study that was the seventh or eighth most commonly identified species, yet had a median maximum abundance of zero due to being absent most of the time except during rare, localized spikes.

Exponential growth

A population growth pattern characterized by a rate that increases or decreases in direct proportion to the current number of individuals; it cannot proceed indefinitely due to space and resource limitations.

Per capita rate of increase ($r$)

The growth rate metric representing population change that increases or decreases in proportion to the current number of individuals in that population.

Cattle egret

An African migratory bird that crossed the Atlantic and expanded into northern California (San Francisco), exhibiting exponential growth as it moves across regions and establishes new niches.

Whooping crane

A large migratory bird species whose numbers fell to just 22 individuals before conservation and restoration efforts allowed it to grow exponentially to over 500 individuals.

Logistic growth

A pattern of population growth in which population size stabilizes and fluctuates slightly above and below a carrying capacity ($K$) in the absence of major environmental changes.

Carrying capacity ($K$)

The stable population size around which a population exhibiting logistic growth can persist indefinitely under relatively constant environmental conditions.

$K$-selected species

Species characterized by logistic growth, slower reproductive rates, smaller numbers of offspring, parental care, and territoriality, which tend to stabilize near carrying capacity.

Harbor seal

A mammal species illustrating logistic growth, exhibiting rapid growth during population establishment followed by stabilization around its carrying capacity.

Four processes of population change

The four fundamental demographic events responsible for all changes in population size: births and immigration (which increase numbers) and deaths and emigration (which decrease numbers).

Population size ($N$)

The standard variable used in population growth formulas to denote the total number of individuals present in a population at a specific point in time ($t$).