Name: ____ANSWER SHEET_____ Period: ________ Date: _____________
Evolution D.A. Study Guide
Test Date: __________________
Use this worksheet as a guideline to help you study for the upcoming Evolution District Assessment. Answers can
be found in your textbook, journal entries, directed readings, and notes we have done during this unit.
Part 1: Evolution and Geologic Time
1.
What is an adaptation? List some examples of animals and the adaptations that help them survive.
A characteristic that improves an individual’s ability to survive and reproduce in a particular environment
Examples- Long neck, striped fur
2.
Define evolution.
The process in which inherited characteristics within a population change over generations such that new
species sometimes arise.
3.
How can one population branch off into two different species over time?
Through the three steps of speciation-1. Isolation (separation) 2. Adaptation (through Natural Selection)
3. Divergence
4.
What is a fossil? How do fossils form? Why is the fossil record so incomplete?
The remains or physical evidence of an organism preserved by geological processes.
They are formed when a dead organism is covered by layer of sediment. Over time, more sediment settles
on top of the organism. Minerals in the sediment may seep into the organism and gradually replace the
organism with stone. If the organism rots away completely after being covered, it may leave an imprint of
itself in the rock.
The organism has to be “lucky.” The right conditions have to be met and then if it becomes a fossil, it must
be discovered.
5.
What is a homology? Give some examples.
The similarity of the body parts in animals that share a common ancestor (they have inherited the same
traits).
Example- Forelimbs of mammals/vertebrates
6.
What is an analogy? Give some examples.
Similar characteristics that evolved independently in different species (NOT inherited from the same
common ancestor).
Convergent evolution- When two unrelated species converge on the same adaptation for a similar
function.
7.
What is a vestigial structure? Give some examples.
A body part that no longer serves any function.
Human - Appendix, tailbone, wisdom teeth, goose bumps, ear muscles; Animal - pelvic bone in whales and
snakes
8.
How does the fossil record provide evidence for evolution?
Provides evidence about the order in which species have existed. Scientist observe that all living
organisms have characteristics in common and inherit characteristics in similar ways. Scientists think that
all living species descended from common ancestors. Evidence of these ancestors are found in the fossil
record.
9.
What do mutations in DNA have to do with evolution?
Mutation is a random change/mistake in the genetic code (DNA). A mutation could change the gene
enough to lead to a different trait that could be passed on to offspring.
10. Who is Charles Darwin? What did he do?
Charles Darwin was a naturalist who developed the theory of natural selection (which was the first correct
mechanism for evolution)
a. How did Thomas Malthus influence Darwin’s thinking?
Malthus pointed out that the human population over-reproduces and there were more people
than what their resources could support.
b. What type of evidence (that is available today) did Darwin lack that now help support his theory?
DNA (genetics)
11. What is Natural Selection?
a. What are the five parts of natural selection?
Overproduction – Inherited Variation – Struggle to Survive – Successful Reproduction - Adaptation
b. How did the Peppered moth display natural selection?
Individual moths cannot decide to change their color. The population had 2 varieties (light and
dark) because of a random mutation. The dark variety was able to survive on the dark trees while
the light ones were not.
12. What is selective breeding? Give some examples.
Human practice of breeding animals or plants that have certain desired characteristics.
Examples: Dogs, fruits/vegetables
13. Examples of natural selection (review pages 122 – 123)
a. How is the example of the tuskless elephants an example of natural selection?
People hunt elephants for their tusks (ivory is very valuable). As a result, fewer of the elephants
that have tusks survive to reproduce, and more of the tuskless elephants survive. When the
tuskless elephant go on and reproduce, they pass the tuskless trait to their offspring
b. Insecticide or antibiotic resistance
An insecticide will kill most insects, but a few may survive. These survivors have genes that make
them resistant to the insecticide. The survivors reproduce and pass the insecticide resistance
genes to their offspring. In time, the replacement population of insect is made up of mostly
individuals that have the insecticide resistance genes.
14. What is the difference between absolute and relative dating?
Absolute Dating- method of measuring the age of an object or event in years
Relative Dating- method of determining whether an event or object is older or younger than other events
or objects
a. Which type is more accurate?
Absolute Dating
b. What do scientists examine for each type of method?
Absolute Dating- radioactive decay of atoms (half-life)
Relative Dating- estimating the age of rocks and fossils based on its position in sedimentary rock
15. Precambrian Time
a. What type of gas did cyanobacteria put into Earth’s early atmosphere? ___oxygen__
b. How did this gas benefit the rest of life on earth? Some of the oxygen formed a new layer of gas
in the upper atmosphere. This gas, now called ozone, absorbs harmful radiation from the sun.
Before ozone formed, life existed only in the oceans and underground. The new ozone layer
reduced the radiation on Earth’s surface
16. Paleozoic Era
a. Greek meaning: “___ Ancient Life___”?
b. Age of the “Invertebrates, Fish and Amphibians”
c. Beginning of most of today’s modern phyla (mollusks, arthropods, vertebrates, echinoderms, etc.)
17. Mesozoic Era
a. Greek meaning: “_____Middle Life_____”?
b. Age of the ___Reptiles__?
18. Dinosaur extinction
a. What and where is the Chicxulub Meteorite impact crater? It is the crater that was created by a
meteor that hit the earth at the end of the Mesozoic era. It is located in modern day Mexico (in
the Gulf of Mexico).
b. What is the K-T boundary?
19. Cenozoic Era
a. Greek meaning: “___Recent Life____”?
b. Age of the ___mammals____?