Charles Darwin
Darwin developed the theory of ___________________.
natural selection
How many types of natural selection are there?
3
True or False?
Evolution takes only a couple generations to change a population.
False
True or False?
Natural selection and evolution occurs at the level of an organism.
False
the gradual change in a species over time
evolution
How did the finches on the Galapagos islands differ from each other?
they had differently shaped beaks
Which type of natural selection favors one extreme of a trait?
directional selection
_____________ are the preserved remains of once-living organisms that provide evidence of evolution.
Fossils
Populations have traits that occur in differences, also known as _______________.
variations
English natural scientist who formulated a theory of evolution by natural selection
Charles Darwin
Identify three types of organisms Darwin observed on the Galapagos Islands.
tortoises, finches, iguanas
In human birth weights, very low or very high birth weights are less common because babies with average weights have a better chance of survival.
What type of natural selection is being described?
stabilizing selection
Organisms that share similarities as they develop from a fertilized egg are studied in the biological field called _______________.
embryology
Organisms will produce (more than enough/just enough/less than enough) offspring in order to ensure some survive to reproduce.
more than enough
a trait that helps an organism survive and reproduce
adaptation
Darwin theorized that all of the tortoises he observed on the ____________ Islands were related to a ___________ ancestor, but that they _____________ separately.
Galapagos; common; evolved
In a population of insects, a scientist found that smaller and larger insects survived and had offspring, but that the predators in this environment ate the medium-sized insects.
What type of natural selection is being described?
disruptive selection
Organisms that share sequences of __________ are hypothesized to be closely related through evolution.
DNA
Organisms that have more beneficial traits in their environment are more likely to do two things. What are they?
1. survive
2. reproduce
ability of an organism to survive and reproduce in its environment
fitness
What was the name of the book Darwin authored that suggested all living things evolved from a common ancestor?
"On the Origin of Species"
The evolution of longer necks in giraffe populations have enabled them to reach higher leaves on trees for food.
What type of natural selection is being described?
directional selection
Scientists have discovered that the fin bones of a whale are similar to bones found in other organisms. Name two of them.
cat, human, bat
Beneficial traits that help organisms in a population survive will
a. always be expressed in the parent generation.
b. be passed on to the next generation.
c. spread to all organisms in an environment.
d. all of the above
b. be passed on to the next generation.
the variety of different types of genes in a species or population
genetic variation