BSC 2011 Exam 3

At the beginning of May, 259 butterflies are found in a certain locality. During the month, 45 butterflies emigrate, 10 die, and 67 immigrate into the area. There are no butterfly births. What is the population size at the end of the month? -249 -271 -281 -346 -192

-271

A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Calculate an estimate of the number of individuals added to (or lost from) a population of 1,000 individuals in one year. -120 individuals added -40 individuals added -20 individuals added -400 individuals added -20 individuals lost

-40 individuals added

Which statement about the human intestine is false? -It can act as an ecosystem for bacteria. -It is densely populated with bacteria. -It receives a steady supply of nutrients. -Its environment is regulated within narrow physiological limits. -All of the above are true; none is false

-All of the above are true; none is false

A cow ingests 100 kilojoules of energy from eating the grass of which 60 kilojoules are egested. An additional 30 kilojoules of energy are lost through respiration. The assimilation efficiency of the grass the cow ate: -Can be calculated by subtracting the energy egested from the energy ingested -Is 10%. -Can be calculated by dividing the assimilated energy by the ingested energy -Can be calculated by dividing the assimilated energy by the egested energy. -Is 40%.

-Can be calculated by dividing the assimilated energy by the ingested energy.

An organism living in the climate depicted in the below Walter Climate diagram would most likely have the following adaptation(s) EXCEPT: (high precipitation, frowny face temperature) -C3 photosynthetic pathway -Produce antifreeze proteins -Endothermic -Concentrated urine

-Concentrated urine

Which process does not occur in ecosystems? -Energy flows through the system. -Carbon is cycled between biotic and abiotic forms. -Producers convert light energy into chemical energy. -Consumers directly use the energy source that powers the system.

-Consumers directly use the energy source that powers the system.

Which statement best describes the interaction of energy and materials, or the process of ecosystem function, within an ecosystem? -Both energy and materials cycle through biotic, but not abiotic, components. -Energy and materials both travel throughout ecosystems, but they follow separate, disconnected routes. -Energy and materials enter biotic components through primary producers; energy flows one way and materials cycle. -Materials travel through ecosystems in one direction and are constantly replenished; energy cycles are used over and over. -Energy cycles through biotic components; materials cycle through abiotic components.

-Energy and materials enter biotic components through primary producers; energy flows one way and materials cycle.

Which example best describes both an elemental pool where an element accumulates and an elemental sink where it is removed from circulation and locked up for long periods? -Fossil fuel deposits in which carbon is stored for hundreds of millions of years -Calcium in bones, which remains fairly stable throughout an animal's life -Sulfur compounds, which react with water to produce acid precipitation -Atmospheric oxygen levels, which are maintained stable by photosynthesis -Nitrogen that is made available to plants from their bacterial endosymbionts

-Fossil fuel deposits in which carbon is stored for hundreds of millions of years

Which of the following would be considered a biotic factor in the environment of an aquatic mammal? -Gut flora -pH -Salinity -Temperature -Oxygen concentration

-Gut flora

Which of the following species has the highest assimilation efficiency? -Herbivorous insect -Insectivorous bird -Deer -Lion

-Herbivorous insect

Which statement best describes an important distinction between the BD model and the BIDE model? -In the BD model, death rates can never be less than zero. In the BIDE model, the death rate can be less than zero. -In the BIDE model, birth rates can never be less than zero. In the BD model, the birth rate can be less than zero. -In the BIDE model, once the density equals zero, it remains at zero. -In the BD model, density can go from zero to non-zero. -In the BD model, once the density equals zero, it remains at zero. In the BIDE model, density can go from zero to non-zero. -In the BD model, birth rates can never be less than zero. In the BIDE model, the birth rate can be less than zero.

-In the BD model, once the density equals zero, it remains at zero. In the BIDE model, density can go from zero to non-zero.

Which is a major assumption of the BD model of population change? -Populations always grow. -Populations are limited by a fixed carrying capacity. -Once an organism has acquired a unit of some resource, this resource can be used for only one function at a time. -Individuals do not move into or out of the population. -Population growth is density dependent.

-Individuals do not move into or out of the population.

Which statement about ecological interactions is false? -Intraspecific competition has no effect on carrying capacity. -Interspecific competition can lead to evolution. -In mutualisms, each species acts in its own self-interest. -Resource partitioning can lead to the coexistence of two competing species. -Intraspecific competition can lead to evolution.

-Intraspecific competition has no effect on carrying capacity.

Which of the following is a likely explanation for why invasive species take over communities into which they have been introduced? -Invasive species are less efficient than native species in competing for the limited resources of the environment. -Invasive species are not held in check by the predators and agents of disease that have always been in place for native species. -Invasive species have a higher reproductive potential than native species. -Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive.

-Invasive species are not held in check by the predators and agents of disease that have always been in place for native species.

What is one application of the metapopulation concept? -It provides a framework for species conservation when those species live in a network of habitat fragments and reserves. -It demonstrates how the many populations of different species can coexist within a community. -It predicts the carrying capacity of populations that exhibit limited growth. -It explains why some populations have a clumped dispersion pattern.

-It provides a framework for species conservation when those species live in a network of habitat fragments and reserves.

Under the conditions known as El Niño, the inorganic nutrient content of the seawater off the coast of Peru declines to very low levels. What effect will this likely have on marine life in the area? -The lower the levels of minerals, the less polluted the water; hence, most populations will increase. -It will result in toxic red tides, which will reduce the populations of many species. -It will reduce the abundance of phytoplankton and, consequently, the abundance of other organisms. -It will increase the productivity of phytoplankton and, therefore, the productivity of other organisms by allowing sunlight to penetrate deeper into the ocean.

-It will reduce the abundance of phytoplankton and, consequently, the abundance of other organisms.

Why do some invertebrates, such as lobsters, show a "stair-step" survivorship curve? -Many invertebrates mate and produce offspring on multiyear cycles. -Within a species of invertebrates, younger individuals have a higher survivorship than older individuals. -Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage. -Many invertebrate species have population cycles that go up and down according to the frequency of sunspots. -The number of fertilized eggs that mature to become females in many species of invertebrates is based on the ambient temperature.

-Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage.

Which of the following statements best describes the interaction between fire and ecosystems? -Fires maintain the low, widely scattered vegetation found in deserts. -Many kinds of plants and plant communities have adapted to frequent fires. -Unlike northern coniferous forests, temperate broadleaf forests contain many species that depend on fire to regenerate. -Chaparral communities have evolved to the extent that they rarely burn. -Fire is unnatural in ecosystems and should be prevented.

-Many kinds of plants and plant communities have adapted to frequent fires.

Which statement about movement corridors is true? -Movement corridors can connect otherwise isolated habitat patches. -Movement corridors can promote inbreeding in declining populations. -Movement corridors are detrimental to species that migrate between habitats seasonally. -Movement corridors can prevent the spread of disease.

-Movement corridors can connect otherwise isolated habitat patches.

Which of the following statements best describes the effect of climate on biome distribution? -Average annual temperature and precipitation are sufficient to predict which biome will be found in an area. -Seasonal fluctuation of temperature is not a limiting factor in biome distribution if areas have the same annual temperature and precipitation means. -Not only is the average climate important in determining biome distribution but so is the pattern of climatic variation. -Temperate forests and grasslands are different biomes because they receive a different quality and quantity of sunlight, even though they have essentially the same annual temperature and precipitation. -Correlation of climate with biome distribution is sufficient to determine the cause of biome patterns.

-Not only is the average climate important in determining biome distribution but so is the pattern of climatic variation.

If an overlap develops between the ranges of two closely related species, and if the species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap? -A new species will arise by hybridization. -Both species will coexist, provided the environment in the zone of overlap is different from that in either individual range. -Both species will coexist, provided the environment in the zone of overlap is similar to that of one of the individual ranges. -One species will take over most or all of the zone of overlap.

-One species will take over most or all of the zone of overlap.

An organism living in the climate depicted in the below Walter Climate diagram would most likely have the following adaptation(s) EXCEPT: (frowny face temperature, low precipitation) -CAM photosynthetic pathway -Outer body covering highly permeable to water -Concentrated urine -Ectothermic

-Outer body covering highly permeable to water

Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada, where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe? -Labrador does not get enough rainfall to support the subtropical flora found in Land's End. -Regions such as Labrador are actually colder than England because colder Arctic water flows down to eastern North America and warm water from the equator flows to England. -Rainfall fluctuates greatly in England; rainfall is consistently high in Labrador. -Labrador is too windy to support tall plants, such as palm trees. -Labrador receives sunlight of lower duration and intensity than does Land's End.

-Regions such as Labrador are actually colder than England because colder Arctic water flows down to eastern North America and warm water from the equator flows to England.

The flux that is responsible for transferring carbon from the land to the atmosphere is called: -Dissolution -Assimilation -Photosynthesis -Outgassing -Respiration

-Respiration

A biology student takes fish, algae, pond plants, invertebrates, and bottom sediment from a local pond and establishes them in an aquarium. When the system is stable, the student seals it into a large, airtight glass box and leaves the box in a sunny location. After 3 months, the organisms in the aquarium appear alive and healthy. Which statement about the experiment is true? -No energy has entered or left the glass box during the 3 months. -Some of the energy in the system has moved from one organism to another during the 3 months. -The air in the glass box contains no carbon dioxide. -During the 3 months, the biomass of animal life was greater than the biomass of plant life.

-Some of the energy in the system has moved from one organism to another during the 3 months.

The notion of species diversity incorporates which factor(s)? -Species richness only -Species evenness only -Total number of individuals only -Species richness and species evenness -Species richness and total number of individuals

-Species richness and species evenness

Which statement about the nitrogen cycle is true? -The nitrogen cycle requires different types of bacteria. -Nitrogen gas is converted to nitrates in plant leaves. -Nitrogen cannot be cycled through living organisms. -When plants and animals die, nitrogen is removed from the nitrogen cycle.

-The nitrogen cycle requires different types of bacteria.

You are reading the journal of an amateur naturalist who visited the Sonoran Desert in the last century. Which of his descriptions of desert plants would you question? -a plant whose seeds will not germinate unless soaked -a perennial that flowers only after years of vegetative growth and produces a large number of seeds -a late winter hillside covered with wildflowers -a common annual that produces one large seed per plant

-a common annual that produces one large seed per plant

Which of the following describes a Type II survivorship curve? -flat at the start, reflecting low death rates during early and middle life, then dropping steeply as death rates increase among older age groups -dropping sharply at the start, reflecting very high death rates for the young, then flattening out as death rates decline for those few that survive -a constant death rate over the organism's life span -flat at the start, reflecting low death rates during early and middle life, then rising steeply as death rates decrease among older age groups

-a constant death rate over the organism's life span

Which of the following best defines a cohort? -a group of individuals that inhabits a small isolated region within the range for the species -all of the individuals that are annually added to a population by birth and immigration -the reproductive males and females within the population -a group of individuals from the same age group, from birth until they are all dead -the number of individuals that annually die or emigrate out of a population

-a group of individuals from the same age group, from birth until they are all dead

Small areas that are home to a large number of threatened species and an exceptional concentration of species found nowhere else on Earth are called: -biomes. -movement corridors. -biodiversity hot spots. -local populations.

-biodiversity hot spots.

All of these factors reduce the efficiency of energy transfer between trophic levels except: -heat loss due to maintaining homeostasis. -heat loss due to metabolism. -indigestibility of some biomass. -biomass stored as fat or starch. -lack of availability of some biomass

-biomass stored as fat or starch.

All of Earth that is inhabited by life is called the: -atmosphere. -ecosystem. -biosphere. -biome.

-biosphere.

In an average ecosystem, about how much energy is present in the organisms at a given trophic level compared to the organisms at the next higher trophic level? -a tenth as much -half as much -twice as much -ten times as much

-ten times as much

A hypothetical community on a barren mid-Atlantic island consists of two fish-eating seabirds (the booby and the noddy), the fungi and microorganisms that live on the birds' dung, a tick that feeds on these two birds, a cactus, a moth that feeds on cast-off feathers, a beetle that lives on dung organisms, and spiders that eat the other arthropods. There are no other plants and no lichens. Which pair of organism and trophic structure is incorrect? -fungi—detritivores -booby—primary consumer -moth—detritivore -cactus—producer

-booby—primary consumer

Artificially constructed movement corridors: -increase inbreeding. -reduce dispersal. -can be harmful because they allow for the spread of disease. -can be harmful because they create isolated habitats.

-can be harmful because they allow for the spread of disease.

Carbon mainly cycles between the biotic and abiotic worlds through the processes of: -cellular respiration and transpiration. -transpiration and photosynthesis. -evaporation and photosynthesis. -cellular respiration and photosynthesis.

-cellular respiration and photosynthesis.

Net primary productivity (NPP) of a community is approximately equivalent to: -gross primary productivity (GPP). -energy used in respiration per unit time. -change in the biomass of primary producers per unit time. -energy captured by plants from sunlight per unit time. -gross primary productivity (GPP) plus respiration (R).

-change in the biomass of primary producers per unit time.

During ecological succession, the species composition of a plant community generally: -changes from a diverse community in which many plants are common to one in which a few species are numerically dominant. -remains stable as long as climate and human interference remain constant. -changes gradually because each species responds differently to the changing environment. -changes until the forest is established and a single species of plant remains.

-changes gradually because each species responds differently to the changing environment.

The pattern of distribution for a certain species of kelp is clumped. The pattern of distribution for a population of snails that live on the kelp would be: -clumped. -random. -uniform.

-clumped.

GPP and NPP are most closely associated with: -community function. -community structure. -species composition. -species richness. -island biogeography.

-community function.

Uniform spacing patterns in plants such as the creosote bush are most often associated with: -chance. -patterns of high humidity. -the random distribution of seeds. -competitive interaction between individuals of the same population. -the concentration of nutrients within the population's range.

-competitive interaction between individuals of the same population.

Deserts typically occur in a band around 30 degrees north and 30 degrees south latitude because: -descending air masses originating from the tropics tend to be dry. -trade winds have little moisture. -moisture-laden air is heavier than dry air and is not carried to these latitudes. -these locations get the most intense solar radiation of any location on Earth.

-descending air masses originating from the tropics tend to be dry.

Studying species transplants is a way that ecologists: -determine the abundance of a species in a specified area. -determine the distribution of a species in a specified area. -develop mathematical models for distribution and abundance of organisms. -determine if dispersal is a key factor in limiting the distribution of organisms. -consolidate a landscape region into a single ecosystem.

-determine if dispersal is a key factor in limiting the distribution of organisms.

The questions of how chemicals flow and energy cycles between organisms and their surroundings are addressed in the study of which level of ecological organization? -community -ecosystem -population -species

-ecosystem

Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive? -community, ecosystem, individual, population -ecosystem, community, population, individual -population, ecosystem, individual, community -individual, population, community, ecosystem -individual, community, population, ecosystem

-ecosystem, community, population, individual

Which of the following terms is used by ecologists to describe the community interaction in which one organism makes the environment more suitable for another organism? -parasitism -herbivory -inhibition -facilitation -commensalism

-facilitation

Factors that help to limit the growth of woody plants in temperate grasslands include: -nutrient-poor soil and high insect diversity. -fires and grazing by large mammals. -large numbers of cacti and small numbers of grazing mammals. -mild winters and low annual precipitation.

-fires and grazing by large mammals.

While on a walk through a forest, you notice birds in trees, earthworms in the soil, and fungi on plant litter on the forest floor. Based on your observations, you conclude that each of these organisms occupies a different: -habitat. -ecosystem. -biosphere. -biome.

-habitat.

An r-selected species typically: -offers considerable parental care to a small number of offspring. -has an advantage in habitats that experience unpredictable disturbances. -is large-bodied, long-lived, and limited by density-dependent factors. -has an advantage in habitats that experience stable climates.

-has an advantage in habitats that experience unpredictable disturbances.

Most plants lack symbiotic nitrogen-fixing microorganisms. An addition of nitrogen gas to these plants would: -increase growth rate by providing additional nutrients. -decrease growth rate by interfering with photosynthesis. -accelerate the metabolic rate by stimulating oxygen uptake. -have no effect, because plants cannot use nitrogen gas. -have no effect, because plants do not require nitrogen.

-have no effect, because plants cannot use nitrogen gas.

Which ecological problem might result from fertilizing a golf course with phosphorus-rich fertilizer? -poisoning of the grass caused by excess phosphorus -heavy growth of algae and cyanobacteria in lakes and rivers caused by phosphorus runoff -accumulation of toxic levels of phosphorus in animals in the vicinity, especially those higher on the food chain -a slowdown in the weathering of rock that releases phosphates into the soil under natural conditions

-heavy growth of algae and cyanobacteria in lakes and rivers caused by phosphorus runoff

A certain species of pine tree survives only in scattered locations at elevations above 2,800 m in the western United States. To understand why this tree grows only in these specific places, an ecologist should: -conclude that lower elevations are limiting to the survival of this species. -study the anatomy and physiology of this species. -investigate the various biotic and abiotic factors that are unique to high altitude. -analyze the soils found in the vicinity of these trees, looking for unique chemicals that may support their growth. -collect data on temperature, wind, and precipitation at several of these locations for a year.

-investigate the various biotic and abiotic factors that are unique to high altitude.

The relationship between ecosystem type and net primary productivity (NPP) in Earth's ecosystems: -decreases as the ecosystem ages. -shows little variability with latitude. -shows little variability with ecosystem type. -is directly proportional to the geographic area the ecosystem covers. -is variable, with some ecosystems responsible for disproportionately more NPP.

-is variable, with some ecosystems responsible for disproportionately more NPP.

Ecological systems are _______ over space and time. -static -unidentifiable -difficult to identify -known to vary -known to stay the same

-known to vary

Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction? -mutualism -commensalism -parasitism -competition -predation

-mutualism

Based on our knowledge of the factors influencing primary productivity, the lowest level of net primary production would most likely be found in forests located in: -Vietnam. -the Amazon. -northern Canada. -the United States. -the African Congo

-northern Canada.

The growing season would generally be shortest in which of the following biomes? -savanna -temperate broadleaf forest -temperate grassland -tropical rain forest -northern coniferous forest

-northern coniferous forest

In addition to abiotic factors, the community composition of plants can be severely compromised by: -parasites and pathogens. -mutualistic birds. -rapid coevolution.

-parasites and pathogens.

The freshwater leech is an organism that feeds off of the blood of other organisms such as frogs and turtles. Which interaction describes the relationship between freshwater leeches and frogs or turtles? -herbivory -predation -mutualism -parasitism

-parasitism

Trees are not usually found in the tundra biome because of -insufficient annual precipitation. -acidic soils. -extreme winter temperatures. -overbrowsing by musk ox and caribou. -permafrost.

-permafrost.

In an ecosystem, you would expect to find interspecific competition between: -males and females of a species in which both sexes occupy the same niche. -populations of two species that occupy the same niche. -a prey species and its predator. -two wasp species that mimic each other's appearance.

-populations of two species that occupy the same niche.

What is a metapopulation? -all of the populations of different species within a community -family units within a single population -populations that are linked by immigration and emigration -the exponential growth in a population's numbers over time

-populations that are linked by immigration and emigration

Which of the following are important biotic factors that can affect the structure and organization of biological communities? -precipitation, wind -nutrient availability, soil pH -predation, competition -temperature, water -light intensity, seasonality

-predation, competition

In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the grasshoppers are: -primary consumers. -primary producers. -secondary consumers. -tertiary consumers.

-primary consumers.

Within an ecosystem, a tree is a: -secondary consumer. -detritivore. -primary consumer. -producer.

-producer.

As you study two closely related predatory insect species, the two-spot and the three-spot avenger beetles, you notice that each species seeks prey at dawn in areas without the other species. However, where their ranges overlap, the two-spot avenger beetle hunts at night and the three-spot hunts in the morning. When you bring them into the laboratory and isolate the two different species, you discover that the offspring of both species are nocturnal. You have discovered an example of: -mutualism. -Batesian mimicry. -commensalism. -resource partitioning.

-resource partitioning.

Many marine phytoplankton construct shells from calcium carbonate (CaCO3). In the carbon cycle, the shells: -are continually broken down, and their carbon is recycled within marine food webs. -are broken apart by waves, and the carbon is released to form carbon dioxide once more. -dissolve back into the water when the organisms die, and the carbon becomes available to new organisms. -sink to ocean sediments when the organisms die, and form limestone, locking up the carbon. -sink to ocean sediments when the organisms die, and because they contain carbon, eventually form fossil fuels.

-sink to ocean sediments when the organisms die, and form limestone, locking up the carbon.

Which of the following is a physical factor that can limit the geographic distribution of species? -predation -disease -soil structure -nutrients -pH

-soil structure

What is an evolutionary factor that influences the species richness of a community? -amount of sunlight -amount of precipitation -speciation rate -geographic size -distance to other communities

-speciation rate

The relative abundance of any one species within a community of many species is known as: -species richness. -species diversity. -species evenness. -specialization. -spatial heterogeneity.

-species evenness.

Resource partitioning would be most likely to occur between: -sympatric populations of a predator and its prey. -sympatric populations of species with similar ecological niches. -sympatric populations of a flowering plant and its specialized insect pollinator. -allopatric populations of the same animal species. -allopatric populations of species with similar ecological niches.

-sympatric populations of species with similar ecological niches.

For conservation purposes, a continuous corridor of habitat would be least needed for a species: -with a metapopulation structure. -that can fly. -with a low birth rate. -with low dispersal ability. -that is wingless.

-that can fly.

A BIDE model of population growth is more applicable than a BD model for a population: -that is part of a metapopulation. -in which reproduction occurs at regular intervals. -that follows multiplicative growth. -in which reproduction occurs at irregular intervals -that is shrinking.

-that is part of a metapopulation.

Gross primary productivity (GPP) and net primary productivity (NPP) are both rates relating to energy use by producers. The key difference between them is that GPP represents: -the energy loss rate, while NPP represents the energy capture rate. -the photosynthetic rate, while NPP represents the respiration rate. -the energy capture rate, while NPP represents the respiration rate. -the energy capture rate, while NPP represents the energy conversion rate. -the photosynthetic rate, while NPP represents the rate of heat loss to the environment.

-the energy capture rate, while NPP represents the energy conversion rate.

Which could be a topic for a community-level study of a hydrothermal vent ecosystem? -the genetic relationships between crabs at the vent and other areas of the ocean -the evolution of a certain species of bacteria in response to the changing composition of the water emitted by the hydrothermal vents -the composition of the water emitted by hydrothermal vents -the interactions between crabs and other species near hydrothermal vents

-the interactions between crabs and other species near hydrothermal vents

What is population dispersion? -the number of individuals per unit area or volume -the pattern of spacing among individuals within the boundaries of the population -the influx of new individuals from other areas -the defense of a bounded physical space against encroachment by others

-the pattern of spacing among individuals within the boundaries of the population

If an ecologist wants to study a system with the least ecological complexity, she should examine one: -with an individual organism interacting with two other organisms of the same species in an isolated community. -consisting of several species of bacteria, yeast, and archaea in one person's gut. -consisting of one species of deer that has overpopulated several states in the Northeast and impacts the survival of other plants and animals in those areas. -in which three animal species feed on two species of plants in one biome in Asia. -with individual organisms of one population that have rapid and localized exchanges with one another and their environment in multiple ecosystems.

-with an individual organism interacting with two other organisms of the same species in an isolated community.

The pool of a phosphorus compartment is 645 units. Two fluxes enter the pool: one is 13 units per day; the other is 34 units per day. Two fluxes leave: one is 22 units per day; the other rate is unknown. If the pool of phosphorus is balanced, the size of the second outgoing flux is _______ units per day. 12 25 47 72 645

25

In an ecosystem, GPP was measured as 75 units of carbon per year and NPP was measured as 25 units per year. How many units of carbon per year was used for respiration? 50 35 75 0

50

If gross primary productivity (GPP) is 120 units per day, and the respiration rate (R) of primary producers is 30 units per day, net primary productivity (NPP) is _______ units per day. [Note: Use the formula NPP = GPP - R.] 4 30 90 120 150

90

multiplicative growth:

In ecology, population growth in which a multiple of the current population size is added to the population during each successive time interval. The multiple of growth may be a constant, or it may change.

geographic range:

The entire region in which a species occurs.

additive growth:

Population growth in which a constant number of individuals is added to the population during successive time intervals.

life history:

The sequence of key events, such as growth and development, reproduction, and death, that occur during the life of the average individual of a given species.

per capita death rate (d)

the average individual's chance of dying

BD Model

the number of individuals in a population at some time in the future = the number now + the number that are born-the number that die N(t+1) = N(t) + B - D *stuff in parentheses is NOT being multiplied, it is a subscript

per capita birth rate (b)

the number of offspring that the average individual produces