Whale Hunting ■ 209(^11) Which of the following is not an example of artificial selection?
(a) Your younger sibling got a hamster as a birthday present, and
it turned out to be pregnant. Several of the offspring had long,
silky hair, and your sibling put them together in an enclosure to
try to produce more baby hamsters with long, silky hair. Your
sibling continued to breed long- and silky-haired hamsters to
each other and now, several years later, your sibling’s bedroom
is full of cages containing long- and silky-haired hamsters.
(b) Your mother has been saving the best seeds from her lima bean
plants every summer and replanting them the next year. She
likes seeds that are plump and bright green and saves only
these each year. Within 10 years, almost all of her lima beans
have become plump and bright green.
(c) Farmer Brown has a duck that can type. He sets up an online
dating profile for his duck to find a female duck that can also
type. Seven years after the arranged wedding of the two typing
ducks, Farmer Brown has an entire flock of ducks, most of
which can type.
(d) Female fish in a natural pond have variable skill at depositing their
eggs near the murky shore, where the eggs are better hidden
from predators. Eggs that are not deposited near the murky shore
are quickly devoured by fish. Female hatchlings from the eggs
deposited near the murky shore grow up to be good at depositing
eggs near the shore and therefore have a survival advantage.
(^12) The fossil record shows that the first mammals evolved 220
million years ago. The supercontinent Pangaea began to break
apart 200 million years ago. On which continents would you predict
that fossils of the first mammals will be found?
Leveling Up
(^13) What do you think? The prerequisites for medical school
application always include courses in cell biology, genetics, and
biochemistry but rarely include a formal course in evolution. Do you
think medical schools should require a formal course in evolution
as a prerequisite for admission? Why or why not? Research the
issue and support your case using information you find from
credible sources.
(^14) Write Now biology: evidence for evolution This assignment is
designed to expand your knowledge of the evidence for evolution.
View the following videos, found at http://www.pbs.org/wgbh/
evolution/educators/teachstuds/svideos.html, and answer the
questions accompanying each one here.
Video 1: “Isn’t Evolution Just a Theory?”
Why is evolution not just a theory? Use specifics from the video
to defend your answer.
Video 2: “Who Was Charles Darwin?”
Why do you think Charles Darwin’s ideas and book On the Origin
of Species were so groundbreaking and “revolutionary”? Use
specifics from the video to defend your answer.
Video 3: “How Do We Know Evolution Happens?”
Describe how the video portrays whale evolution. Include
specific examples of transitional fossils described in the video,
and explain why the scientists at the time the video was made
considered the fossils to be whale ancestors.
Video 5: “Did Humans Evolve?”
DNA sequences of different species can be used to provide
evidence of common descent. Using examples from the video,
explain why DNA sequence similarity is the best evidence of
evolution on Earth.
Video 6: “Why Does Evolution Matter Now?”
Describe why the theory of evolution matters to the field
of medicine and to individual doctors. Use the example of
tuberculosis from the video to support your answer. How does
this video affect your answer to question 13?
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