Evidence & Concepts
This is the preserved remains or traces of organisms from the past; scientists use these to show that life has changed over time
Fossils
The process by which organisms better suited to their environment survive and reproduce more successfully is called this.
Natural selection (or evolution by natural selection)
The term for differences among individuals in a population (examples: height, fur color) is this.
Variation (or genetic variation/phenotypic variation)
When people intentionally choose which organisms reproduce to favor desirable traits in crops or animals, this process is called ___.
Artificial selection (selective breeding)
The study of where organisms live now and where they lived in the past; patterns here can show how species changed as continents moved or climates shifted.
Biogeography
Name one scientist (first and last) who independently developed the idea of evolution by natural selection along with Darwin
Alfred Russel Wallace (or Charles Darwin).
A random change in DNA that can introduce new traits into a population is called a ___.
Mutation
Give one example (short phrase) of how artificial selection has been used in agriculture to reduce pesticide use.
Example: Breeding pest-resistant plant varieties so fewer pesticides are needed
Comparing the body structures of different species (like forelimbs of birds and mammals) to show they share a common ancestor is called this.
Comparative anatomy (homologous structures)
Fill in the condition necessary for natural selection: there must be ___ in traits, traits must be ___, and there must be differential ___.
Variation; inherited; survival (or reproduction/competition).
Through sexual reproduction, offspring receive genes from both parents. What term describes the combination of alleles an organism has (example: Aa, aa)?
Genotype
Identify one tradeoff or downside of using artificial selection to breed pest-resistant crops.
Example: Tradeoff — selecting for one trait can reduce genetic diversity or cause unintended weaknesses (e.g., lower tolerance to drought)
Early-stage development similarities among different species (showing relatedness) are studied in this field of evidence.
Embryology
In the Galápagos, finch beak shapes are used as an example of natural selection. Explain in one sentence how beak shape relates to food source and survival.
Example answer: Beak shape affects which seeds or insects a finch can eat; birds with suitable beaks survive and reproduce more.
A graph showing how common different phenotypes are in a population (for example, flower color frequencies) displays the ___ of traits.
Distribution (or frequency distribution)
Explain how understanding natural selection helps scientists and farmers develop healthier, more productive crops (2–3 sentences)
Example answer: By applying principles of natural selection, breeders/selective programs can identify beneficial traits (disease resistance, drought tolerance) and propagate them to make crops more productive and reduce chemical inputs.
DNA analysis showing degrees of relatedness between species is an example of this kind of evidence for evolution
Explain how competition for limited resources can drive natural selection in a population (brief, 2–3 sentences).
Example answer: When resources are limited, individuals with advantageous traits obtain more resources and reproduce more; over generations these traits increase in frequency.
Describe how a founder effect or a random event (like a wildfire) can change trait distribution in a population (2–3 sentences).
A founder effect or a wildfire can randomly remove individuals so allele frequencies shift by chance; resulting population may have different trait frequencies not due to selection.
Describe how artificial selection is common within dogs?
Artificial selection is highly prevalent in dogs, with humans shaping over 400 distinct breeds by selecting specific traits—such as size, coat color, behavior, and morphology—over thousands of years.