History & Theories of Evolution
What is a scientific theory?
In science, this term refers to a broad explanation supported by repeated observations, experimentation, and evidence.
What does “fitness” mean in evolution?
An organism’s ability to survive and reproduce successfully.
What are fossils?
Preserved remains or traces of ancient organisms.
What is a mutation?
A random change in DNA.
What is a species?
A group of organisms that can reproduce and produce fertile offspring.
What idea about Earth did Hutton and Lyell support?
Earth is millions of years old and changes gradually over time.
What are selective pressures?
Environmental factors that affect survival and reproduction.
What is the difference between relative dating and radiometric dating?
Relative dating compares fossil ages, while radiometric dating gives exact ages using radioactive materials.
Which mutations can be passed to offspring?
Mutations in gametes (egg or sperm cells).
What is allopatric speciation?
The formation of new species due to geographic isolation.
What did Lamarck believe happened when organisms used or did not use certain body parts?
Used body parts became stronger, while unused parts weakened or disappeared.
What is an adaptation?
An inherited trait that helps an organism survive and reproduce.
What are homologous structures?
Body parts with similar structures because species share a common ancestor.
What is genetic drift?
Random changes in allele frequencies, especially in small populations.
What is convergent evolution?
When unrelated species evolve similar traits because they live in similar environments.
What is natural selection?
The process where organisms with helpful traits survive and reproduce more successfully.
Why did black peppered moths become more common during the Industrial Revolution?
Pollution darkened trees, helping black moths camouflage from predators.
What are analogous structures?
Structures with similar functions that evolved independently in unrelated species.
What is the founder effect?
When a small group starts a new population with different allele frequencies than the original population.
How are Darwin’s finches an example of divergent evolution?
One ancestral species evolved into many species adapted to different niches.
What does “descent with modification” mean?
Modern species evolved from common ancestors and changed over time.
Why does natural selection affect populations instead of individual organisms?
Individuals do not evolve; populations change over generations as allele frequencies change.
How do embryos support evolution?
Many species show similar early development, suggesting common ancestry.
How does gene flow affect populations?
It moves alleles between populations and reduces genetic differences.
What is gametic isolation?
When sperm and egg from different species cannot successfully fuse.