7.1 - 7.3 Natural and Artificial Selection Flashcards
What is natural selection?
A process in which individuals that have certain traits tend to survive and reproduce at higher rates than other individuals because of those traits.
Who is Charles Darwin?
An English naturalist known for his research on natural selection and evolution, particularly at the Galapagos Islands.
What is the significance of Darwin’s hypothesis about the Galapagos Islands?
Darwin hypothesized that organisms left South America, colonized the Galapagos Islands, and diversified into new species.
What does ‘survival of the fittest’ mean?
‘Fittest’ refers to the organisms that can survive and reproduce, not necessarily the strongest or healthiest.
What is microevolution?
Small genetic changes within a population that do not lead to the appearance of a new species.
What is macroevolution?
The accumulation of large genetic changes within a population over time, leading to speciation.
What are heritable traits?
Characteristics that can be passed from parent to offspring.
What is artificial selection?
The selective breeding of domesticated plants and animals to encourage desirable traits.
Compare and contrast natural selection and artificial selection?
NATURAL SELECTION occurs in nature without human influence
- nature “selects traits” that are better suited for survival and reproduction
- adaptations become more common
ARTIFICIAL SELECTION occurs with human influence
- humans select traits that are desirable
- domestication of plants and animals
- doesn’t necessarily increase fitness (ex. pugs, bulldogs)
BOTH can lead to evolutionary change
What is the role of competition in natural selection?
Competition for limited resources leads to differential survival, where individuals with more favorable phenotypes are more likely to survive and reproduce.
What is the definition of evolution according to Darwin?
Change in the genetic makeup of a population over time; descent with modification.
What is the impact of environmental changes on natural selection?
Environments can change, applying selective pressures that affect which traits are favorable for survival and reproduction.
What is an example of a misconception about natural selection?
Natural selection gives organisms what they need to survive is FALSE; it acts on genetic variations that lead to survival and reproduction.
What is the significance of adaptations?
Inherited characteristics that enhance an organism’s survival and reproduction.
What does evolutionary fitness measure?
Reproductive success; how well an organism can survive and pass on its genes.
What is the effect of producing more offspring than can survive?
It leads to competition for limited resources and results in differential survival.
A population of pacas losing body mass due to a lack of food is not an example of descent with modification because the change is due to environmental influence.
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