Evidence of species change
Vocabulary
Cause and Effect
100

What does an evolutionary tree show?

The ancestors of a modern species; change over time

100

The "frequency of a gene" means...

What percent of the population has the gene or trait; how common it is

100

If plants are sprayed with herbicide, what happens over time to the percent of the population that has a gene for resistance?

The frequency of resistance increases. Plants without that gene die off and plants with the gene survive exposure and pass it on.

300

Over time, how has tail color changed in this species?

Bright tails have become more common and dull tails have become less common

300

Heritable variations means...

Parents pass down the genes for a trait

300

A gene that helps an individual organism survive and reproduce will become...

a) more common over time

b) less common over time

Helpful traits become more common over time - individuals with that gene are more likely to reproduce and pass it to the next generation

500

How do scientitsHow do scientists use protein similarities to figure out evolutionary relationships?

Species with a more recent common ancestor have fewer amino acid differences

500

Does "evolution" affect one organism, or many organisms?

Evolution is species change - the most common traits in a POPULATION change over time. One plant or animal can't change its traits.

500

Why were there lots of lactose TOLERANT people in agricultural populations that relied on milk for nutrition?

Being lactose tolerant helped people get nutrients and avoid being sick, so people with that gene were more successful at reproducing.

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