Evolution Study Guide Name___KEY______

My child is prepared for Friday’s Test and has completed this study guide ______

Vocabulary: Use the following words to fill in the blanks: genetic variation, mutation, adaptation, sexual selection, evolution, theory, natural selection, artificial selection, genetic drift, migration (gene flow), and reproduction. Some words may be used more than once.

1.  In order for a population to evolve, organisms in the population must have differences or __genetic variations______.

2.  There are 5 mechanisms that change the gene frequencies in a population. They are __gene flow_____ , ____sexual selection______, ______natural selection___, ____mutations______,__genetic drift______.

3.  gene flow______-The chance of an individual migrating to another population and sharing its genes there.

4.  _mutation______- A change in a DNA sequence, usually occurring because of errors in replication or repair.

5.  ___mutation______- The ultimate source of genetic variation.

6.  __genetic drift______- The change in allele frequencies in a population due to random events like habitat destruction which results in changes in successive generations.

7.  ___natural selection______- A process of evolution in which traits that result in better fitness of an individual survives to the next generation. Survival of the fittest!

8.  ___natural selection______- is defined as the process whereby organisms with the best genetic adaptations will survive and reproduce.

9.  __evolution______- Theory in which populations will inherit small changes over time.

10.  A ___theory______is more than an educated guess. It is a widely accepted set of explanations of observations and phenomena.

11.  __adaptation______- An inherited characteristic that increases the chance of survival

12.  In ___artificial selection______, human breeders, rather than the environment, select the variations of traits to be passed to offspring.

13.  Darwin provides a mechanism for evolution to occur. He proposed that _natural selection______took place as individuals best suited to the environment survived and reproduced.

14.  Charles Darwin realized that the measure of success for an organism was not only a long period of survival but also successful _reproduction______.

15.  Every organism must either carry out ___reproduction______or become extinct. ( A characteristic of all living things)

Evidence of Evolution:

1___paleontology______- The study of extinct Life.

·  Fossil records show that species have changed over time. In ___relative _ dating, scientists compare fossils found in different layers of rock to determine the relative age of an organism. In __absolute (radioactive)__dating, scientist look at half-lives of element decay to determine the exact age of a fossil.

2. _Embryology______- The study of organisms at an early stage of development provides evidence of possible common ancestors between two different species.

3. ___homologus structures___- Organs found on different organisms that have similar structures but have evolved different uses for these structures.

4. __Vestigial Structures_- Organs or structures that have been reduced in size in an organism that suggests that they adapted to life without their use.

Darwins 5 Points of Natural Selection

1.  __Variation______- Organisms within a population will have differences.

2.  Within variation, their will be a __favorable______traits______

3.  __Overproduction______- More organisms will be produced than will survive.

4.  Of those organisms that survive, they have a favorable trait that increased their chances of survival called an___adaptation____.

5.  Over time, the environment will have __selected____ a trait that will become more prevalent within the population.

Short Answer:

/ Animals and plants have been selectively bred for generations to produce certain desired phenotypes. This is an example of __artificial selection______. This supports the theory of _evolution______because it shows how organisms can change.
/ Use the peppered moth example to explain Darwin’s 5 points of evolution.
1. ___Variation______– populations have differences. What is the variation in the peppered moth population? __dark and light______
2. Some variations are __favorable______. After the Industrial Revolution, which phenotype is most favorable? __darker______
3. __Overproduction______– More offspring are produced than survive. After the Industrial Revolution, which phenotype survived at a greater rate? _darker moths______
4. _Adaptations______– those that survive are the ones with the favorable traits
5. _Selection______– the population will change over time as a result of passing inheritable traits from adaptations. In time, most of the moth population were of the ___darker______phenotype.
/ This diagram demonstrates the process of ___natural selection ______. It demonstrates that changes in the gene frequency of a population can change the phenotypes of a population. Before the introduction of the predator, each phenotype occurred in equal numbers in the population. After the introduction of the predator the __darker______phenotype is most common. This is because they were able to survive and __reproduce______at a greater rate.

/ There are two ways that scientists date fossils. This picture represents __relative______dating in which the position of fossils in rock layers are used to determine age. Fossils in lower layers are _older______and fossils in upper layers are ___younger_____. In this picture, layer __E__ is the youngest layer and layer ___A_ is the oldest.

/ Darwin cited evidence for the theory of evolution. One of these is represented by this diagram. It shows _Embryology______- the study of organisms at an early stage of development. The similarities in the development of many organisms suggest an __evolutionary______relationship (common ancestor).
Another line of evidence cited in the theory of evolution is represented by this diagram. It is an example of __Vestigial______structures, body parts that are reduced in size and unused in present day organisms.

Suggests that as body part was no longer needed in environment they were lost

/ The diagram below shows ______Homologous______structures, which may not have the same use, but do have a common evolutionary origin, and thus structure. These similarities in body parts suggest a ___Common Ancestor______
/ __Carrying Capacity______– the number of individuals that an environment can support due to environmental pressures.
Explain what each point on the graph shows:
A: Individuals are dying and reproducing at the same rate
B: Population is slowly growing
C: Unlimited resources and not much competition, population is growing fast
F: Possible Answer: Population ran out of resources/ predator was introduced
At which point is the population increasing at the greatest rate? __C______
What caused this population to crash? __Disease/ natural disaster/ Predator
/ Graph 1: Rabbits Over Time
The graph shows ___population of rabbits meeting its carrying capacity
The carrying capacity for rabbits is __65__
During which month did the population of rabbits reach carrying capacity? __August
During which month were the rabbits in exponential growth? __June_____
/ Study the picture to the left. A population of insects is sprayed with a new insecticide. Most of the insects are killed but a few survive. In the next generation, spraying continues, but many more of the insects are unaffected by the insecticide than the first spraying. Which of the following BEST explains these results?
a.  The insecticide caused a mutation in the species.
b.  A few insects in the first population were immune and passed this trait to their offspring.
c.  The insecticide caused a side effect of immunity that was passed on to the next generation of insects.
d.  The insects learned to fight off the insecticide.

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