URI BIO 102 Exam 3 Paim-Pinto Lopez

Example of mutualism

(+/+) bat and bees use the nectar from flowers as a food source and the flower uses the bees and bats as pollinators.

Commensalism

(+/0) least studied interaction because it is difficult to quantify the absence of a cost to the host. Orchids use trees to get closer to sun and rain, but tree isn't harmed. Not to be confused with parasitism in consumption

Net reproductive range

(R0) Indicates whether a population is increasing or decreasing (as long as immigration and emigration are insignificant).

Consumption

(including herbivory, predation, and parasitism) occurs when one organism eats or absorbs nutrients from another. The interaction increases the consumer's fitness but decreases the victim's fitness (+/ -)

The per-capita rate of increase or intrinsic rate of increase

(r) the difference between the birth rate and death rate per individual, r = b-d

2 Components of an ecosystem

1. Community of interacting species present in a region, 2. Abiotic components

Primary producers use this chemical energy in two ways

1. cellular respiration to produce ATP to fuel metabolic processes, 2. growth and reproduction- (NPP)

4 stages of secondary succession

1. pioneering species 2. early successional community 3. mid-successional community 4. climax community

3 stages of primary succession

1. solid rock —weather—> 2. gravel, sand, silt, and clay (also organisms enter this stage and contribute dead cells, tissues, and feces) —time—> 3. complex mixture of inorganic and organic particles and living organisms

Given that r = 0.22, how long will it take the population to double? Nt= N0e^rt

= 3.2 years Nt=2 No=1 r=0.22 t=3.15 2=1e^(0.22*t) --> ln2=0.22t

Natural selection involves energetic trade-offs between _____. A. high survival rates of offspring and the cost of parental care B. the emigration of individuals when they are no longer reproductively capable or committing suicide C. increasing the number of individuals produced during each reproductive episode and a corresponding decrease in parental care D. producing large numbers of gametes when employing internal fertilization versus fewer numbers of gametes when employing external fertilization E. choosing how many offspring to produce over the course of a lifetime and how long to live

A

In general, NPP in the oceans is greatest where? A. Open ocean B. Near coastlines C. Deep waters D. n the northern hemisphere oceans

B

Succesion in an ecological context refers to ____. A. The predictable series of changes in a community as species evolve and become extinct B. The sequence of changes in species composition over time within the community after a disturbance C. What happens to the evolution of species as a result of the co-evolutionary arms race D. The sequence of changes that a species goes through during its occupancy within a community

B

What makes species in late successional communities successful? A.They are short lived B. They are good competitors for resources C. They are able to disperse their seeds over long distances D. They are small

B

Processes that affect population size

Births Deaths Immigration Emigration

A population is growing exponentially and its instantaneous growth rate (r) is 0.02. Would the number of individuals added to the population (rN) be greatest at a population size (N) of 20, 500 or 1000? A. 20 B. All the populations would have the same number of individuals added to them since r is constant C. 1000 D. 500

C

What makes species in early successional communities successful? A. They are naturally selected for longevity B. They outcompete all other species C. They are able to disperse their seeds over long distances D. They are large

C

Which of the following disturbances would result in primary succession? A. Fire B. Hurricane C. Volcano D. Logging

C

Which two biomes is NPP the greatest in per unit area?

Coral reefs and tropical wet forests

If you are concerned about biomagnification, then what would be the worst choice to eat for lunch? A. garden salad B. veggie pizza C. shrimp cocktail D. yellow-fin tuna salad

D

The study of factors that determine the size and structure of populations through time is called _____. A. Community ecology B. Logistic growth C. Immigration biology D. Demography

D

When primary producers invest energy to build new tissue, this is _____________? A. Maintenance costs and the amount of energy available to consumers B. Net primary productivity C. Maintenance costs D. Net primary productivity and the amount of energy available to consumers E. The amount of energy available to consumers

D

Which of the following terms defines how the individual organism allocates resources to growth, reproduction, and activities or structures related to survival? A. Energy budget B. Demography C. Survivorship D. Life history

D

Which of these statements is true regarding biomagnification? A. Bioaccumulation is a concern for primary consumers but not secondary consumers. B. Primary producers have the highest concentrations of toxins. C. Bioaccumulation is not influenced by geography or eating habits. D. Bioaccumulation is a concern for secondary and tertiary consumers.

D

Why does net productivity diminish with increasing trophic levels? A. There are fewer plants at higher trophic levels. B. Energy is gained a each trophic level. C. Organisms at a higher trophic level have to work less to obtain food. D. There is poor trophic transfer efficiency at higher trophic levels.

D

Exponential growth is density dependent or independent

Density independent and occurs when per capita growth rate is constant

Logistic growth rate is density dependent or independent

Diversity dependent and occurs when the population size approaches the carrying capacity and growth rate decreases

5 Levels of Ecological Study

Global Community Population Ecosytem Organismal

Life History Fitness Trade-Offs. High/low fecundity vs high/low survivorship

High fecundity- low survivorship (small plant) Low fecundity- high survivorship (palm tree)

Graphing Exponential growth high r vs low r steepness

High r: steep Low r: not steep

Population

How and why does population size change over space and time

Organismal

How do individuals interact with each other and their physical environment

Community

How do species interact, and what are the consequences

Ecosystem level

How does energy flow and how do nutrients cycle through the local environment

Global level

How is the biosphere affected by global changes in nutrient and climate

Exponential growth curve shape

J

Primary productivity equation

NPP = GPP - CR

R₀

Net reproductive rate- indicates whether a population is increasing or decreasing (as long as immigration/emigration are insignificant)

Change in NPP for each hemisphere and why

Northern: increased in NPP (more CO2, higher temperature), Southern: decreased in NPP

How many years will it take the coral population to reach 20 individuals? (t)

Nt = 20 N0 = 2 r = 0.69 20 = 2e (0.69)(t) 10 = e (0.69)(t) ln10= 0.69(t) t =3.38

A pair of corals was introduces to new habitat in 2014. Assume these corals only breed once per year. In 2015 there were two pairs. What is the intrinsic rate of increase? (r)

Nt = 4 4 = 2 e r(1) 2 = e r(1) ln 2 = r(1) r = 0.69

Continuous growth equation

Nt = N₀e∧rt

Which two biomes have the highest % of the earth's NPP per unit area?

Oceans and tropical wet forest

Survivorship (Ix)

Proportion of the offspring produced that survive

Logistic growth curve shape

S

Three ways that niches change in response to competition between specie, Outcome 3

Species coexist when one or more changes its niche

Wolf and moose shows that

Species interactions can affect the distribution and abundance of a particular species

Three ways that niches change in response to competition between species, Outcome 1

The competitive exclusion principle states that it is not possible for species within the same niche to coexist

Three general types of survivorship curves

Type I Type II Type III

When does r reach a maximum value, rmax

When birthrates per individual are as high as possible and death rates per individual are low as possible

Three ways that niches change in response to competition between species, Outcome 2

When one species is more competitive and niches do not overlap completely, weaker competitors use non-overlapping resources

Does r have max?

Yes, r has a max

Quanitfying Population Growth

a populations growth rate is the change in the number of individuals in the population (delta N) per unit of time (delta t).

Niche differentiation or resource partitioning

an evolutionary change in resource use that occurs when species compete for many resources

Niche differentiation

an evolutionary change in resource use, caused by competition over generations

Density dependent

any characteristic that varies depending on population density or affects carrying capacity. Ex. colonization of a new habitat, recovery after disaster, predation, competition, toxic waste, disease, social behavior

b

birth rate per individual

Blue carbon

carbon stored by coastal and marine ecosystems

K stands for

carrying capacity- the maximum number of individuals in a population that can be supported in a particular habitat over a sustained period of time

Character displacement vs. disruptive selection differences

character displacement occurs as a result of interactions between 2 different species when disruptive selection occurs among only 1 species that form into 2

Defenses to consumption

constitutive and inducible

Herbivory

costuming plant and algal tissues

Why is change in NPP in the oceans potentially harmful

currents are less likely to bring nutrient-rich water to surface against the steep density gradient when water is much warmer

A population of animals in a specific environment with a carrying capacity of 2500 has an r of 1.0 per individual per year and exhibits logistic growth. Considering a population size of 750 individuals, by how many individuals is the population increasing per year?

dN= 525 K=2500 r=1 N=750 dN = ? dN/dt = 1*750 (2500-750)/2500 dN/dt = 525

Exponential growth equation

dN÷dt = rN

Logistic growth rate

dN÷dt= rN(k-N/K)

d

death rate per individual

Productivity declines/increases at higher trophic levels

declines

How does energy flow through ecosystems

decomposer <—> (sunlight~~>) primary producer —> primary consumer —> secondary consumer —> tertiary consumer (~~> heat)

NPP is increasing or decreasing on land? ; in the oceans?

decreasing; decreasing

Continuous Growth equations

delta N - ——— = rN delta t -N(subscript t) = N(subscript 0)e^rt

Population growth equation

delta n ------- = (b-d)N delta t

Logistic growth is density independent/dependent; which means its growth rate is

dependent; growth rate slows at high density, early growth is rapid, growth begins to slow, the growth falls to zero

Secondary succession

disturbance removes some or all of the organisms but leaves the soil intact. ex.- fire and logging

Primary succession

disturbance removes the soil and organisms. ex.- glaciers and volcanic eruptions

The outcome of interactions among species is _____

dynamic and conditional, interactions can change from mutualism to consumption or to other types

Net Primary Productivity (NPP)

energy invested in new tissue or offspring is called net primary productivity (45% of GPP, other 55% goes out in cellular respiration)

These two components are linked by the flow of ______ and the cycling of ______ needed to sustain life

energy; materials

Density independent

factors such as variation in weather or catastrophic events. Ex. hurricanes, tornados, wildfire

g stands for

generation time

dN/dt

growth rate of the population in a given instant

Is biomagnification beneficial or harmful to humans

harmful

Three types of consumption

herbivory, predation (can be herbivores that eat an entire plant or a seed, parastism

Type 3 curve

high death rates for larvae or seedlings but high survival rates later in life; insects and plants, sea turtles

For biomagnification, is there an increase or decrease in concentration of pollutants at higher levels in the food chain

increase

Inducible defense, def, pros, and cons

induced in the presence of a consumer. Pro- saves energy, Con- takes time to induce, ex.- mussels develop thicker shells in the presence of crabs

Late successional communities: adult size, growing speed, offspring size, dispersal, competitiveness

large adults, slow, few large offspring, low dispersal, are competitive

Does r ever reach maximum

most likely no, environment is not perfect. Hypothetical

N stands for

number of individuals

N₀ stands for

number of individuals at time 0 or initial generation size

Competition

occurs when individuals use the same resources— resulting in lower fitness for both (—/ —) Ex. lion and hyena

Commensalism

occurs when one species benefits but the other species is unaffected. (+/0) Ex. epiphytic orchids and their host trees

Mutualism

occurs when two species interact in a way that benefits both (+/+). Ex: bees and flowers

Which biome has the highest % of the earth's NPP?

open ocean

r stands for

per capita rate of increase- the difference between birthrate and death rate per individual

R0 < 1

population is decreasing

R0 > 1

population is increasing

R0 = 1

population is stable

N↓t stands for

population size at the end of time

Realized niche

portion of the fundamental niche that a species actually occupies, given limiting factors such as competition with other species (seats left after others are sitting

Constitutive defense, def, pros, and cons

present even in the absence of consumers. Pro- defense is always present, Con- costs a lot of energy, ex.- grasshopper resembles leaf

Which is slower to occur, primary or secondary succession

primary

An alternate way to calculate r

r= lnR(subscript 0) / generation time *g*

Which equation to calculate population growth

r=lnR₀/g

Community dynamics, Succession

recovery that follows a severe disturbance (natural disasters)

Type 2 curve

same probability of dying in each year of life; songbirds, lizards

Early successional communities: adult size, growing speed, offspring size, dispersal, competitiveness

small adults, fast growing, many small offspring, high dispersal, not competitive.

What does the life table do?

summarizes the probability that an individual will survive and reproduce in any given time interval over the course of its lifetime

Type 1 curve

survivorship is high throughout life then drops in old age; humans, big mammals

Life Table, --> survivorship, fecundity, average births per year per female

survivorship: % that survived out of the original number (lx) fecundity: The number of female offspring produced by each female in the population (mx) average births per year per female = lxmx

Autotrophs

synthesize their own food from inorganic sources. ex. sunlight= photosythesis (not creating energy, just converting from solar to chemical)

Which marine ecosystems have the greatest NPP and why?

the coastlines because the rivers and upwellings carry nutrients to the ecosystems on the coastlines so there are more nutrients for primary producers

Character displacement

the evolutionary tendency for the traits of similar species that occupy overlapping ranges to change in a way that reduces interspecific competition

Is NPP higher on land or in the sea and why?

the land because there are primary producers because there is more light available on land than in the water

N

the number of individuals

Number of Survivors (Nx)

the number of individuals that survived to reach each age class

Niche

the range of resources that the species is able to use, or the range of conditions it can tolerate.

Demography

the study of factors that determine the size and structure of populations through time

Gross Primary Productivity (GPP)

the total amount of chemical energy produced in a given area and time period

Biomass

the total amount of chemical potential energy that is stored in organic material

How does energy enter an ecosystem

through primary producers

t stands for

time

Character displacement vs. disruptive selection, similarities

two bell shaped curves are moving away from each other

Where on land is NPP the greatest and why?

wet tropics because they get the highest availability of sunlight, increase in temperature, abundance of water

Parasitism

when a parasite consumes relatively small amount of tissue or nutrients from a host.

Predation

when a predator kills and consumes all or most of another individual. The consumed is the prey

Nectar cheaters

when a showy bright flower doesn't have nectar, becomes (+/—)

Exponential Growth (r doesn't change) axis labels

x axis: generations y axis: population size (N)