Rev 3 Flashcards
(25 cards)
What was the name of the ship on which Darwin sailed and when did it sail?
HMS Beagle, 1831-1836
List a few of the locations where Darwin made some of his key observations.
- Galápagos Islands
- South America
- Australia
- Africa
Give a specific example of an observation that helped Darwin start to believe that some modern day species could be related to now extinct species.
The fossil records of giant armadillos resembling modern armadillos
What did he notice with certain types of birds and tortoises as the ship sailed south or went from island to island?
Variations in beak shapes of birds and shell shapes of tortoises
What did Darwin conclude was causing the changes in the related organisms that he observed?
Natural selection
What was different about the finches on the different islands, and what did he believe was the specific reason/factor that may have caused the difference?
Beak size and shape differences due to food availability
At the same time, which geologist claimed that the Earth was very old and constantly changing?
Charles Lyell
How are farmers able to improve (change) their crops and livestock?
Through selective breeding
What is the name that Darwin gave to this type of selective breeding program that farmers have used?
Artificial selection
List a few factors that Darwin suggested prevent natural populations from over-running the Earth.
- Competition for resources
- Predation
- Disease
- Environmental changes
Give the definition of Natural Selection.
The process where organisms better adapted to their environment tend to survive and produce more offspring
What actually happens to population numbers over time despite the ability to produce far more offspring?
Population numbers tend to stabilize or decrease
What happens to those members who do not have favorable traits?
They are less likely to survive and reproduce
Explain how Darwin would explain the adaptations of long legs and webbed feet of frogs.
These traits enhance their ability to survive and reproduce in aquatic environments
What is the selection that selects one variation in a population?
Directional selection
What type of natural selection allows more than one extreme phenotype to survive?
Disruptive selection
Which type of selection tends to keep a population stable in appearance?
Stabilizing selection
Give a specific example of Directional Selection.
The increase in size of the peppered moth in response to pollution
Give a specific example of Stabilizing Selection.
Human birth weight where extreme weights are selected against
Which type of selection can give rise to two new species?
Disruptive selection
What usually happens to abnormal varieties during Stabilizing Selection?
They tend to be eliminated
What usually happens to abnormal varieties during Disruptive Selection?
They may become more common and lead to speciation
What was the name of the competing theory that Lamark theorized explained evolution?
Lamarckism
Briefly describe the experiment that shows that acquired characteristics cannot be inherited.
Experiments with cut tails in mice showed that offspring did not inherit the trait
