A increase population size
could not be caused by a population bottleneck.
What is true about the amoeba population?
It is more vulnerable to extinction due to lack of genetic variation. The amoebas might not have the variation necessary to adapt to future changes in the environment.
True or False?
In the example described in the tutorial, the red amoebas survived the catastrophic event, and all future generations of amoebas were red because the red amoebas had a higher reproductive rate than the blue ones. FALSE.
Genetic Drift
A change in the allele frequency of a small population purely by chance.
Bottleneck Affect
A large reduction in the size of a population as a result of a catastrophe or other event. A population bottleneck often results in a change in the allele frequency of the population (genetic drift).
Environmental Change
A drought causes a habitat to turn dry and brown.
Selective Pressure
Green beetles are more visible to birds than brown beetles, so birds eat more green beetles.
Change in Population
Brown beetles survive to reproduce more than green beetles do. The brown allele increases in frequency.
A single, small population that only exists in one place on the planet is considered_______to that area.
In England, dogs with large, floppy ears called hounds came into existence. These dogs were favored for hunting because of their excellent sense of smell. Which statement most accurately represents the process that produce such dog breeds from the wild-type (feral) dog?
Humans noticed dogs with large, floppy ears and a great sense of smell and wanted more like them. They then bred with similar dogs over many generations. This is called ARTIFICIAL SELECTION and is one of Darwin's points of evidence for evolution by natural selection.
human-induced events
The sixth mass extinction event is likely being caused by___________.
Two organisms live in the same geographical area, are very similar genetically, and can breed with each other successfully. Which of the following statements is correct?
These organisms are members of the same species.
a single fish living in the lake's shallow water near the shoreline.
a group of fish of the same species inhabiting the shallow water near the shoreline.
fishes, invertebrates, plants, and microbes inhabiting the shallow water near the shoreline.
the fishes, invertebrates, plants, microbes, rocks, sediments, and water in the lake, and the interactions between them.
several interacting species living in the same area.
____________typically have a mortality rate that remains fairly constant over an individual's life span.
Oyster populations are primarily, if not exclusively, composed of ____________.
Which of these organisms has a survivorship curve similar to that of oysters?
Which of these organisms has a survivorship curve similar to that of humans?
Which of the following statements are true of logistic growth?
-As the population approaches carrying capacity, it grows more slowly. -When the population reaches carrying capacity, it stops growing.
Which of the following are true of a population at carrying capacity?
-The population growth rate equals zero. -The birth rate equals the death rate. -The rate at which resources are used is equal to the rate at which they are supplied.
As a population approaches carrying capacity, environmental resistance__________.
The factors that do contribute to environmental resistance are:
competition for food, environmental toxins, weather conditions, and competition for space. Birth rate does not contribute to environmental resistance.
exponential growth
An ideal habitat with unlimited resources is associated with______________.
carrying capacity
The maximum population a habitat can support is its ___________________.
Logistic growth involves...
...Population growth slowing down as the population approaches carrying capacity.
In exponential growth...
...Population size grows faster and faster as the population gets bigger.
Which of following would NOT cause population size to decrease?
Increased birth rate
biotic potential
The innate reproductive capacity of a species is its __________________. If a parasitic worm makes a very large number of eggs, it has a high biotic potential. These animals are called r-strategists. Elephants have a low biotic potential by comparison, and are called K-strategists.
density-dependent factor
Food availability decreases as population increases.
density-independent factor
An oil spill's effect on population does not depend on population size.
density-dependent factor
Space limitations cause birth rate to decline as population size increases.
density-dependent factor
Predation becomes more intense as population size increases.
parental care of young
Which of the following is a typical K-selected species' adaptation?
Which of these best matches with a type III survivorship curve?
an organism that produces huge numbers of offspring, most of which die quickly, with the few survivors not dying until old age. -Many amphibians produce hundreds or thousands of eggs, but only a few survive until adulthood. This a type III survivorship.
When looking at the distribution of a population, we might find a uniform distribution when_____________
individuals are competing for an evenly distributed resource such as space.
An insect species is an agricultural pest. It is small, extremely mobile, and reproduces rapidly.
The inspect species is r-selected.
Why are island species particularly vulnerable to introduced species?
Island species evolved in isolation and lack defenses against introduced species.
Which of the following is a major reason that Hawaii has been able to prevent some species from going extinct?
People are protecting public and private land.
loss of habitat
is the biggest factor in the declining pheasant population in Iowa?
You are an Iowa farmer and you'd like to set aside some of your highly erodible land and plant it with native plant species. What should you enroll in?
Conservation Reserve Program
As ____ prices increase, land values increase.
In ____, as pheasant numbers have decreased, the number of pheasant hunters has also decreased.
You wish to go pheasant hunting in Iowa. Why will you likely have to find a private land owner willing to allow you to hunt?
There is very little public land in Iowa.
Farm bill
The future of the pheasant in Iowa is strongly tied to this piece of federal legislation.
Gene flow
is the migration of individuals or gametes.
change in the allele frequencies in a population is the definition of microevolution.
may or may not have played a role, in flight, courtship, gliding, and extended hops.
Adaptive Radiation
is rapid, branching speciation under conditions in which there is little competition.
Adaptive Radiation
Mass extinctions create conditions that promote______________.
Adaptive Radiation
The appearance of an evolutionary novelty often promotes________________.
Adaptive Radiation
The different finch species found on the Galapagos Islands probably arose as a result of ______________.
formation of oxygen
Which of these events occurred earliest in the history of Earth?
first humans
Which of these events occurred most recently in the history of the Earth?
colonization of land by plants
Which of these events occurred during the Paleozoic?
in the South Pacific
Where are the Solomon Islands located?
white-eye bird
Scientists studying evolution on the Solomon Islands described which animal as the 'poster child' for the biological species concept?
Based on the video, what can you infer about speciation--the process by which one species splits into two or more species?
Physical separation of populations is often part of the speciation process.
Its call was unique.
Why did the biologists consider a frog that they found to be a new species?
When Darwin wrote On the Origin of Species, he knew very little about the subject of_____________, an essential component of evolutionary theory today.
In order for two organisms to belong to the same species, individuals of their species MUST____________.
be able to reproduce and have fertile offspring.
Which of the following is NOT a way that two populations of the same species can be geographically isolated?
Individuals in one population mate during a different month than individual in another population.
An excellent example of selective or artificial breeding by human is____________.
The diversity of dog breeds in the world today.
natural, rate
Extinction is a ____________ process; human activity can affect the __________ at which extinction occurs.
a mutation
The only process that can change a gene's DNA and therefore give rise to new genetic variations in a species.
Which statement below most accurately describes a phylogenetic tree?
A phylogenetic tree is a branching diagram used to illustrate a scientist's hypothesis about how divergence took place among evolutionary lines.
Convergent Evolution
Bats and birds are unrelated animals, yet they both evolved wings. By acquiring similar traits (i.e., wings) as they adapted to similar environments, these species exhibit____________?
a small, endemic population
Which of the following populations would be MOST vulnerable to extinction?
mass extinction events
Which of the following would explain the extinction of upwards of 90% of species in existence over a short period of time?
According to the figure, which of the following is true?
Snakes are more closely related to crocodiles than they are to turtles.
According to the figure, crocodiles are most closely related to____________.
A speciation event
Each branch in the figure results from______________.
is a natural process.
An ecosystem...
...encompasses all the organisms and the physical and chemical environment within an area.
...on Earth today are but a fraction of all species that ever lived.
Biodiversity is...
...the variety of life in all its forms and combinations and at all levels of organization.
A population is....
...a group of individuals of a single species that live and interact in one area.
Endemic species_____________.
are found only in one place on the planet.
sexual reproduction
What is the key mechanism maintaining genetic variation in most populations?
Heavy rains and mudslides cause a river to change course, isolating two groups of lizards from one another. If they remain isolated for a long period of time, ____________________.
The groups will probably diverge genetically, and speciation may occur.
Which of the following would be most vulnerable to extinction?
An orchid endemic to a forest where logging is occurring.
One example of artificial selection is__________________.
the generation of broccoli and brussels sprouts from a single ancestral species.
phylogenetic trees
Scientists often depict their understanding of an organism's evolutionary ancestry in diagrams called________________.
A species has evolved an asexual mode of reproduction by having offspring develop from unfertilized eggs. Which of the following will be true of this species' response to natural selection?
There will be less genetic variation from recombination and a risk of not adapting quickly to environmental change.
the biosphere
Which of the following in the broadest (most all-encompassing) level of ecological organization?
A_____________is defined as the living and nonliving elements around an organism.
The living and nonliving components of systems in operating in conjunction with each other.
What does an ecosystem ecologist study?
population, community, ecosystem, biosphere
Starting with the smallest level of ecological organization and moving towards the highest, the order should go organism,_______________.
ecosystem ecologist
If a scientist spends his time studying communities and the nonliving materials that they interact with, he or she would be called an__________________.
Many interacting species that live in the same area
Communities and the abiotic material which their members interact.
specific environment in which an organism lives.
Population Density
Number of individuals within a population per unit area.
Convergent Evolution
The process by which unrelated species acquire similar traits.
Species occurring in only one area.
The functional role of a species in its community is its___________________.
a generalist, able to be flexible
A coyote can alter its diet to match seasonal abundance of plants, fruits, or small animals, and would therefore be considered___________________.
You are doing a mark-recapture experiment to determine the population size of the MendAliens living on an island in my back yard. Initially, you catch and mark 130 MendAliens, which you then release. Next, you capture 90 MendAliens, of which 20 are marked. What is your estimate of the population size of MendAliens living on the island in my back yard?
To get the population size N, multiply the number marked in the first catch, M1, by the total number caught in the second catch, C, and divide that by the number of marked recaptures in the second catch, M2: N = (M1 x C) / M2 Or: (130 x 90) / 20 = 585.
Assume there are 200 MendAliens living on an island in my back yard. If my island has an area of 20 hectares, what is the population density of MendAliens in terms of MendAliens per hectare?
Population density is calculated as population size divided by area: 200 MendAliens / 20 hectares = 10 MendAliens per hectare.
The mark-recapture method would be best for sampling a population of______________.
Population Density
What describes the number of individuals in a population per unti area?
sex ratio
When a scientist looks at the ________________of a population, he or she is examining the proportion of males to females in the population.
What expression is used to determine the overall growth rate of a population?
(crude birth rate-crude death rate) + (immigration rate-emigration rate)
Carrying Capacity
The maximum population size that a given environment can sustain.
Density-dependent factors
have a greater impact at higher population densities.
natural rate of population growth
If we are not concerned about the effect of migration on population growth, the measure we could calculate is the _________________.
dissolved oxygen levels
Consider a population of fish in the ocean. Which of the following would be a limiting factor for such a population?
2,000 individuals
Assuming a population grows by a fixed percentage each year, which of the following starting populations would experience the biggest increase in its population from one year to the next?
High population density can________________.
Increase the incidence of disease transmission.
Population distribution describes_____________________.
the spatial arrangement of individuals of a single species within a particular area or ecosystem.
exponential growth
Unregulated populations tend to increase by ___________________________.
Density-dependent factors
include the effects of disease, predators, and food on a single species within a community.
Groups of organisms with low biotic potential, such as gray whales, _______________.
are K-selected.
type II survivorship
Population in which the probability of dying is constant at every age exemplify _______________.
logistic growth
An S-shaped population growth curve best describes________________.
Which of the following would best represent a clumped population distribution pattern?
a pod of 40 migrating gray whales in the Bering Sea