Download 7 th Grade Life Science Evolution Study Guide - Mrs. Nolan

7th Grade Life Science
Evolution Study Guide
Define the Following:
1. Adaptation: A characteristic that improves and individual’s ability to survive and reproduce in a
particular environment.
2. Natural Selection: the process by which individuals that are better adapted to their environment
survive and reproduce more successfully than less well adapted individuals do; a theory to explain
the mechanism of evolution.
3. Fossil record: A historical sequence of life indicated by fossils found in layers of the Earth’s crust.
4. Evolution: The process in which inherited characteristics within a population change over
generations such that new species sometimes arise.
5. Selective Breeding: The human practice of breeding animals or plants that have certain desired
traits.
6. Species- A group of organisms that are closely related and can mate to produce fertile offspring.
7. Speciation: the formation of new species as a result of evolution.
8. Mimicry: The ability of certain organisms to copy their environment or another organisms for their
survival.
Use the words you just defined to complete the following sentences:
9. When a single population evolves into two populations that cannot interbreed anymore, Evolution has
occurred.
10. Darwin’s theory of Natural Selection explained the process by which organisms become well-adapted to
their environment.
11. A group of organisms that can mate with each other to produce offspring is known as a(n) Species.
12. The Fossil Record provides information about organisms that have lived in the past.
13. In Selective Breeding, humans select organisms with desirable traits that will be passed from one
generation to another.
14. A(n)Adaptations helps an organism survive better in its environment.
15. A scientist is studying fossils found in the Georgia Coastal Plain. Fossil A resembles Fossil B, but Fossil B
was found in a deeper layer than Fossil A. Briefly describe the relationship between the fossils.
The resemblance of Fossil A and Fossil B tell scientist that they may have shared a common ancestor, and
because Fossil B was found in a deeper layer it is an older fossil than Fossil A.
A population of lizards is separated when a canyon forms. The process of erosion widens the canyon, and
the lizards become further separated.
16. How will scientists know when the original species of lizard becomes two new species?
Scientist will know that speciation has occurred when the three steps have taken place.
1. Separation (geographic isolations) The eroded canyon
2. Adaptation (natural selection occurs and selects the most beneficial traits)
3. Division (over time the two separated groups have changed so much that they are no longer able to
successfully reproduce together and a new species has been created)
17. Why did this change most likely occur?
Punctuated Equilibrium: Due to the separation of the original species by the eroded canyon the lizards
had to adapt to their new environment and evolve.
18. Briefly describe the process of Natural Selection by answering the following questions:
- How does it work?
Organisms able to adapt are better suited to their environment survive and reproduce more successfully
than less well adapted organisms of the same species.
- How long does it take?
Natural Selection can take as long as an organism needs to adapt to their environment; it usually can take
thousands to millions of years to take place
- What is the purpose of Natural Selection?
The purpose of Natural Selection is for organisms to survive their environment and successfully
reproduce.
- What is an example of Natural Selection?
An example of Natural Selection is the peppered moth simulation when the moths became darker over
time due to the soot covered trees caused by the industrial revolution. The moths needed to blend in with
its environment to avoid their
18. In the space provided below, graph punctuated equilibrium & gradualism.
Punctuated Equilibrium
Punctuated Equilibrium states that organisms
will go unchanged/unevolved until something
drastic happens to separate a species, such as a
natural disaster.
Gradualism
Gradualism states that evolution is always
occurring slowly and steadily over time
without anything causing it to happen.
24. Describe the following about Charles Darwin.
- Who was he?
He was the naturalist that came up with the evolution theory of Natural Selection.
-What Islands did he visit?
Galapagos Island
- What did he study on those islands?
He studied Finches
- What did he learn about evolution and how did he know this?
He learned that organisms adapt to their environment to be better suited to their environment, and he
saw it in the species of finches and their different beaks depending on the food sources available.
Vestigial Structures:
Are body structure that has no purpose in a present day organism, but was probably useful to an ancestor.
Example: The human appendix was once thought to help digest raw meat.
Homologous Structures:
Body parts from organisms of different species that are similar in structure and suggest the organisms share a
common ancestor.
Example: