Download B 262, F 2005 – KEY Name

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BIOLOGY 262, FALL 2005 – KEY
EXAMINATION #2 (PART 1)
Date
MULTIPLE CHOICE.For the following multiple choice questions circle the letter in front of the
response that best answers the question or completes the sentence. (20%, 2% each)
6. Which of the following traditional
1. Which of the following is an assumption
Linnean taxonomic ranks is just “above”
of scientific philosophy?
Class (the next most inclusive taxon)?
a. Different events cannot have the
a. Genus
same cause.
b. Kingdom
b. Only experimental observations can
c. Order
prove hypotheses to be true.
d. Phylum
c. Senses never reflect reality.
e. Species
d. The universe is ordered.
e. None of the above. (None are assumptions)
7. Which of the following is when a
bacterium takes in DNA from the
2. In a population at Hardy-Weinberg
environment around the bacterium?
equilibrium, if the frequency of AA is
a. binary fission
0.09, then what is the frequency of Aa?
b. conjugation
a. 0.03
c. transcription
b. 0.21
c. 0.33
d. transformation
d. 0.49
e. None of the above
e. None of the above = 0.42
8. If a population of 1,000 is undergoing
exponential growth with a yearly
3. As described in The Evolution Explosion
intrinsic rate of increase of 0.50 then what
Alexander Flemming Discovered the
is the size of the population after 2 years?
antibiotic penicillin by…
a. 500
a. conducting clinical trials.
b. 750
b. examining competition among soil
c. 1500
bacteria.
d. 2000
c. inadvertently curing a skin infection
e. None of the above. = 2250
when working with penicillin.
d. observing a mold inhibiting growth
in a bacterium on a Petri dish.
4. Death of small and large sparrows during
storms as described in The Evolution
Explosion is an example of…
a. artificial selection.
b. directional selection.
c. disruptive selection.
d. sexual selection.
e. stabilizing selection.
5. Which of the following is an assumption
of the Hardy-Weinberg theorem?
a. genetic drift occurs
b. gene flow occurs
c. mutation occurs
d. natural selection occurs
e. random mating occurs
9. If a population of 2,000 is undergoing
logistic growth with a yearly intrinsic rate
of increase of 0.10, and a carrying
capacity of 4000 then what is the size of
the population after 1 year?
a. 2000
b. 2100
c. 2200
= 2199.75
d. 4000
e. None of the above.
10. Which of the following is a correct
species name?
a. Staphylococcus aureus
b. Staphylococcus Aureus
c. Staphylococcus
d. aureus
e. None of the above
SHORT ANSWER.For the following briefly answer as appropriate. (10%)
1. Look at the real data below. Male
2. Identify three things that are “wrong” or
widowbirds have long tails. Males with
misleading about this illustration. (6%)
more nests in their territories have more
offspring. Nests are built by females who
select among males.
Mean number of nests in each territory
Normal males = 0.9
Males with lengthened tails = 1.9
Males with shortened tails = 0.3
Briefly explain what the data above
show and indicate which evolutionary
phenomenon this demonstrates. (4%)
(Hint, this example is from p. 473 in the textbook.)
a. Depicts evolution as linear.
This is sexual selection because
females are clearly selecting males
based on tail length. On average,
Longer Tail = More Nests
b. Depicts evolution as progressive.
c. Always male (and always a man
of European descent at the right)
DEFINITIONS.For the following BIOLOGICAL words or phrases define them as accurately and
concisely as possible. (20%, 4% each)
1. Biological Evolution:
Change in the intrinsic (genetic) qualities of life over time.
2. Biological Species Concept:
A species is the largest unit of population in which genetic exchange is possible and that
is genetically isolated from other such populations.
3. Evolutionary Species Concept:
A species is a lineage of ancestor-descendant populations that maintain their own
identity and has its own evolutionary fate.
4. Natural selection:
Differential survival based on differences in inherited characteristics (genes). (or any of
the other definitions)
5. Science:
A belief that natural phenomena have natural causes that can be revealed by empirical
evidence.
BIOLOGY 262, FALL 2005, EXAMINATION #2 (PART 2)
Date
Name
FREE RESPONSE QUESTIONS/PROBLEMS.For the following, address each in as concise and lucid a
manner as possible. Do NOT exceed the space provided. (50%)
1. Use the data below to construct a phylogenetic tree of the species in the left column. Show the derived traits
on your phylogenetic tree. OG = Outgroup
Antelope
Cow
Whale
Walrus
Wolf
Opossum OG
(14%)
horns
stomach
chambers
carnassial
teeth
pouch
hooves
present
present
absent
absent
absent
absent
4
4
4
1
1
1
absent
absent
absent
present
present
absent
absent
absent
absent
absent
absent
present
present
present
absent
absent
absent
absent
carnassial
teeth
Wolf
Seal
Whale
no
pouch
four
chambered
stomach
Cow
horns
hooves
Antelope
2. On August 27th 1883 the island Krakatau in Indonesia exploded in a volcanic eruption that destroyed all life on
the island. The species found on the island after the eruption were monitored by biologists. The land birds and
plants found on the island are presented during the 100 years after the eruption. The survey in 1933 found the
island to be covered in a rainforest similar to those found nearby islands. (12%)
Dates when surveys
occurred
# of land
bird species
# of plant
species
1883
1908
1919
1933
1951
1984
0
13
28
29
33
36
0
105
216
271
285
291
b) Name and BRIEFLY explain, in 1-2 sentences, the
process whereby an island of bare rock in 1883 became
an island covered by tropical rainforest 50 years later.
Krakatau Bird Species 1883-1984
#
a) Appropriately graph the number of species of birds and
plants on the island after the eruption. (Label axes.)
What pattern do both exhibit? Suggest an explanation
for this pattern.
Krakatau Plant Species 1883-1984
#
1883
1984
time
1883
1984
time
b) This is (primary) ecological succession, change in
community composition over time (often caused by intraspecific competition).
a) Rapid recolonization
(during early succession)
followed by a slowing of the
rate of increase in species
richness as the climax
community is approached
(could mention
competition). (NOT logistic
growth which is a
populational , not a species
richness phenomenon)
3. Answer the following based on this hypothetical scenario. The Regis
Regis Island
Island tortoise lives in two populations on Regis Island, one in the
northeastern lowlands and the other in the southwestern lowlands. Both
maintain an approximately constant population size. This tortoise cannot
survive for long at higher elevations in the mountains at the center of the
island. However, individuals occasionally move through a mountain pass in
the north and across a very narrow lowland area to the southeast. Breeding
Regisiba Island
the in this tortoise requires a warm moist breeding season, because of climate
North
is at the top of the map
in the northeast breeding never occurs in the northeast population.
a.) Briefly describe the subpopulation/interpopulational dynamics between the northeastern and southwestern
Regis Island populations. Indicate which Regis Island population would be most important to preserve if
people were going to destroy the tortoises’ natural habitat to build a hotel and why. (4%)
The southwestern population is clearly a source population that
provides individuals to offset the death rate in the northeastern
population (in which reproduction does not occur). Because of
this the southwestern population is more important for tortoise
conservation, because if it is destroyed or seriously negatively
affected, the northeastern population would disappear as well
In 1980 a few biologists discovered four Regis Island tortoises on Regisiba Island, an island that previously had
no tortoises. It was thought that they may have floated there on mats of vegetation from Regis Island after a very
very rare hurricane. Tortoises cannot swim. The population on Regisiba was counted every 5 years, 1980-4
tortoises, 1985-10 tortoises, 1990-250 tortoises, 1995-750 tortoises, 2000-900 tortoises, 2005-910 tortoises.
b.) Explain the pattern of population growth of the Regisiba tortoises below and briefly explain what caused it to
proceed in this way. (4%)
This is clearly an example of logistic growth in an environment with many resources
colonized by a few individuals. Eventually, the limits of the resources are reached
and the size of the population remains at the carrying capacity.
In 2005 people studied the population genetics of the “A” gene in 200 individuals each from each population.
southwestern Regis Island population – 32AA, 96Aa, 72aa.
Regisiba Population – 200AA, 0Aa, 0aa.
northeastern Regis Island population – 35AA, 146Aa, 19aa.
c.) Briefly provide the most plausible evolutionary explanation for why the Regisiba population has such different
allele and genotype frequencies than the Regis Island populations? (4%)
This is likely due to the genetic drift that is the result of the Founder effect. (It may
also have been or the founder effect may have been supplemented by the
homozygosity caused by inbreeding among the earlier generation.s.)
d.) Is each of the two Regis Island populations at Hardy-Weinberg equilibrium? Show calculations and indicate
what your results suggest about evolution with respect to the A gene in each population. (12%)
southwestern population – p = 160/400 = 0.40; q = (240/400 =) 0.60
p2 = (0.40)2 = 0.16,
2pq = 2 x 0.40 x 0.60 = 0.48,
q2 = (0.60) 2 = 0.36
(multiply by 200)
expected #s = 32AA, 96Aa, 72aa = observed – at Hardy-Weinberg = NOT evolving
northeastern population – p = 216/400 = 0.54; q = (184/400 =) 0.46
p2 = (0.54)2 = 0.29,
2pq = 2 x 0.54 x 0.46 = 0.50,
q2 = (0.46)2 = 0.21
(multiply by 200)
expected #s = 58AA, 100Aa, 42aa ≠ observed – NOT at Hardy-Weinberg = EVOLVING
(probably lower survival of aa homozygotes)