APES Unit 3 Pt. 1 Vocab

Population

Population refers to the total amount of individuals in a species in a particular region. Understanding populations is essential for studying various aspects of life, society, and ecosystems.

Exponential Growth (J)

A J shaped curve that describes the comparison between time & population size (N_t = N₀e^rt)

Resource partitioning

Resource partitioning is when resources are divided to avoid competition for a limited resource.

Community 

A community consists of the various interacting populations within an ecosystem. A community can be exemplified by all of the living organisms existing within a deciduous forest – animals such as hawks, snakes, deer, & rabbits, deciduous trees & other plants, as well as bacteria and fungi – which all interact within their environment.

Predation

A biological interaction where one organism, the predator, kills and eats another organism, its prey.

Population Ecology

Population ecology is a subfield of ecology that deals with the dynamics of species populations and how these populations interact with the environment, such as birth and death rates, and by immigration and emigration.

Logistic Growth (S)

When a population's growth rate decreases as population size approaches a maximum imposed by limited resources or the carrying capacity. 

Population size

The total number of individuals within a defined area at a given time.

Population Density

the number of individuals per unit area at a given time.

Overshoot

When a population becomes larger in numbers and exceeds its carrying capacity.

Population Distribution 

From an environmental standpoint, population distribution refers to the spatial arrangement of populations within a specific geographical region and its impact on the natural environment. It examines how  resource utilization affect ecosystems, biodiversity, and the overall sustainability of the environment in a given area.

Die-Off 

A rapid decline in population size when carrying capacity is exceeded and resources are limited. 

Sex Ratio

The ratio between the number of males and females, expressed as the number of males per 100 females.

K-selected species

K-selected species is the population of a species thats grows slowly until it reaches the carrying capacity.

Age structure

The proportionate numbers of people in different age categories in a given population for a defined time.

R-Selected Species 

R-selected species are recognized by high growth rates, typically exploit less-crowded ecological niches, and produce many offspring. 

Predator-mediated competition

The competition between between different species that is influenced by the presence of predators. It occurs when predators target and consume certain species more than others, leading to a decrease in the population of the prey species. 

 Density-dependent factors

The population size will influence an individual’s probability of survival. 

Survivorship Curves

A survivorship curve is a graph that shows the number or proportion of individuals surviving to each age for a given species or group.

Ecosystem Engineers

Keystone species that create habitats for other species.

Carrying Capacity

Largest number of individuals of a population that an environment can support.