Environmental Science Learning Objectives and Study Questions
Chapter 3: Withgott and Laposata, 5th ed.
1. Define a species and explain how natural selection can act within a population of organisms to produce a
new species.
2. List two sources of genetic diversity that can produce the adaptive traits upon which natural selection acts.
3. Sketch a phylogenetic tree (or a cladogram) for a group of organisms based on information about the traits
they share.
4. List three characteristics that might make a particular species particularly susceptible to extinction and
contrast the rates of environmental change during mass extinction events with those during times of
background extinction.
5. Define ecology and contrast what an ecologist would be studying if he or she were interested in learning
about a population, community, ecosystem, or landscape.
6. Contrast how organisms’ niches and their abilities to utilize a variety of habitats are likely to differ between
specialists and generalists.
7. List the five metrics used to describe a population of organisms and briefly describe what each tells us about
the character of that population.
8. Calculate the growth rate of a population using information on its birth, death, immigration, and emigration
rates.
9. Determine whether or not a population of organisms has likely reached its environment’s carrying capacity
by examining a graph of population size versus time.
1. The tendency of adaptive traits to become more widespread in a population over time because the
organisms that have them live longer or produce more offspring is known as _____.
A. convergent evolution
B. dumb luck
C. karma
D. mutation
E. natural selection
2. On a phylogenetic tree (or cladogram) organisms close to
one another _____.
A. always share a predator-prey relationship
B. appeared at the same time in Earth’s history
C. rarely coexist in the same ecosystem
D. share few common traits
E. share many common traits
3. All of the following are likely to make a species more vulnerable to extinction except _____.
A. being endemic to a specific region
B. being a generalist
C. being narrowly specialized to a specific resource or role
D. living in an isolated (e.g. island) environment
E. having a small population size
4. The study of living organisms, their non-living environment, and the interrelationships among them is known
as _____.
A.
B.
C.
D.
E.
demography
ecology
etymology
paleontology
taxonomy
5. If an organism’s niche is its “profession” its habitat is its “_____”.
A. address
B. annual income
C. hobby
D. social status
E. typical behavior
6. Organisms typically have a uniform spatial distribution if _____.
A. predators are a constant threat
B. resources are plentiful and do not strongly influence where they settle
C. resources or habitats are unevenly spaced
D. they cannot see or smell very well
E. they compete with one another for space
7. Suppose that a population has an annual: birth rate of 20/1000, death rate of 18/1000, immigration rate of
2/1000, and emigration rate of 5/1000. What is the growth rate of this population in percent?
A. - 0.1 %
B. 0.0 %
C. 0.1 %
D. 0.2 %
E. indeterminate, we cannot tell from what we know