Population Ecology

Question 1

The geographic distribution of a species is determined by a combination of _____________________, which together shape where a species can live, grow, and reproduce.

Answer 1

Abiotic and Biotic

Question 2

Individuals are aggregated in patches or clusters. This is the most common type of distribution and often results from the availability of resources or social behaviors.

Answer 2

Clumped Distribution

Question 3

An example of __________________ is in some species, individuals form groups for cooperative behaviors like hunting (e.g., wolves) or protection (e.g., schools of fish).

Answer 3

Clumped Distribution

Question 4

Individuals are evenly spaced throughout their environment. This distribution is typically observed when organisms are territorial or actively compete for limited resources.

Answer 4

Uniform (Even) Distribution

Question 5

Species that defend territories (e.g., birds, some mammals) will tend to space themselves evenly, with individuals occupying distinct areas. This is an example of ____________.

Answer 5

Uniform (Even Distribution)

Question 6

Individuals are dispersed without any apparent pattern. This occurs when resources are plentiful and there are no strong social or competitive interactions between individuals.

Answer 6

Random Distribution

Question 7

refers to the reproductive output of an individual, or more specifically, the number of offspring produced by an individual or group during a given period of time.

Answer 7

Fecundity

Question 8

are used to track survival and reproduction rates in populations and to understand how populations grow or shrink over time. They provide insights into survivorship, fecundity, and mortality at different life stages.

Answer 8

Life Tables

Question 9

In this type, most individuals live to old age, and mortality is concentrated in older age classes. Young individuals have a high probability of surviving, and most deaths occur later in life due to factors like disease, aging, or predation as they age. This pattern is typically seen in species with high parental investment in offspring, meaning that parents invest a lot of time and resources into raising their young, which increases their chances of survival to adulthood.

Answer 9

Type 1 Survivorship Curve

Question 10

In this type, the probability of surviving is constant throughout the life span, meaning that individuals have a roughly equal chance of dying at any age. Mortality is steady across all age groups, and the population faces consistent mortality risk throughout its life. This type of curve is often associated with species that are subject to constant environmental hazards or uniform predation risk throughout their life.

Answer 10

Type 2 Survivorship Curves

Question 11

In this type, there is high mortality in the early stages of life, with very few individuals surviving to adulthood. However, once the individuals reach a certain age or size, their chances of survival increase significantly. This pattern is characteristic of species that produce a large number of offspring but provide little to no parental care. The large number of offspring increases the likelihood that some will survive to adulthood, but most die young due to predation or other environmental factors.

Answer 11

Type 3 Survivorship Curves

Question 12

Examples of Type 1 Curve Organisms

Answer 12

Humans, Elephants, Large mammals

Question 13

Examples of Type 2 Curve Organisms

Answer 13

Songbirds, Some reptiles, Rodents

Question 14

Examples of Type 3 Curve Organisms

Answer 14

Oysters, Sea turtles, Dandelions

Question 15

Mortality Pattern of Type 1 Curve

Answer 15

Mortality concentrated in older age classes.

Question 16

Mortality Pattern of Type 2 Curve

Answer 16

Mortality is constant throughout life.

Question 17

Mortality Pattern of Type 3 Curve

Answer 17

High mortality in early life, low mortality in adulthood.

Question 18

Nt​ = N0 × 2 ^(t/g)

Answer 18

Bacterial Growth Formula

Question 19

Variable t in Bacterial Growth

Answer 19

the population size at time t (the number of bacteria after a given period of time).

Question 20

Variable 0 in Bacterial Growth

Answer 20

the initial population size (the number of bacteria at the start).

Question 21

Variable g in Bacterial Growth

Answer 21

the generation time (the time it takes for the population to double).

Question 22

describes the unrestricted growth of a population under ideal conditions where resources are abundant and there are no significant environmental constraints. It leads to unlimited growth and is represented by a J-shaped curve.

Answer 22

Exponential Growth

Question 23

occurs when a population’s growth is constrained by limiting factors, and it stabilizes as the population approaches the carrying capacity (K) of its environment. It is represented by an S-shaped curve.

Answer 23

Logistic Growth

Question 24

S Curve

Answer 24

Logistic Growth

Question 25

J Curve

Answer 25

Exponential Growth

Question 26

(denoted as K) is the maximum population size that an environment can sustain indefinitely given the available resources (such as food, water, shelter, and mates) and environmental conditions (like climate and predation). Beyond this point, the environment can no longer support additional individuals, and the population will stabilize, with growth slowing or even declining.

Answer 26

Carrying Capacity

Question 27

Bacteria are continuously supplied with nutrients, and waste products are continuously removed. This type of environment mimics natural conditions where resources are replenished over time, and bacteria can grow without the limiting factors typically present in closed systems.

Answer 27

Open Cultures