biology- evolution

• What is the definition of evolution?

  Evolution is the change in the characteristics of a species over time.
• How does evolution occur?

  It occurs over many generations and is driven by genetic changes.
• What can evolution lead to?

  It can lead to the formation of new species.
• What is an example of evolution in horses?

  The evolution of horses from small, multi-toed animals to larger, single-toed animals over millions of years.
• What is natural selection?

  Natural selection is the primary mechanism driving evolution.
• Who first described natural selection?

  Charles Darwin.
• What happens to organisms with advantageous traits in natural selection?

  They are more likely to survive and reproduce.
• What occurs to beneficial traits over time in a population?

  Beneficial traits become more common in the population.
• How does natural selection affect a population of rabbits with longer ears?

  The proportion of rabbits with longer ears would likely increase.
• What is genetic variation?

  Genetic variation is the diversity in gene forms (alleles) within a population.
• Why is genetic variation crucial for evolution?

  It provides the "raw material" for natural selection to act upon.
• How does genetic variation affect a species' survival?

  It increases the chances of a species surviving environmental changes.
• What is an example of genetic variation in Galápagos finches?

  Genetic variation in beak shape allowed some finches to survive when food sources changed.
• What is adaptation?

  Adaptation is the process by which organisms become better suited to their environment.
• What results from natural selection acting on genetic variation?

  Adaptation occurs.
• What types of adaptations exist?

  Adaptations can be structural, physiological, or behavioral.
• How do adaptations affect an organism's fitness?

  They increase an organism's fitness, or ability to survive and reproduce.
• What is an example of an adaptation in polar bears?

  The thick blubber of polar bears is an adaptation to their cold Arctic environment.
• What is evidence for evolution?

  Evidence for evolution comes from various scientific fields.
• What are the key sources of evidence for evolution?

  1. Fossil record: Shows changes in species over time 2. Comparative anatomy: Reveals similarities in body structures across species 3. Embryology: Demonstrates similarities in early development stages of different species 4. Molecular biology: Shows genetic similarities between related species 5. Biogeography: Explains the distribution of species across the globe
• What does the fossil record show about whales?

  The fossil record of whales shows a transition from land-dwelling ancestors to fully aquatic mammals over millions of years.
• Which evidence would provide the strongest indication of a new mammal species evolving from a mainland ancestor?

  The presence of vestigial structures similar to those found in a mainland species.
• Which type of evidence provides the most direct evidence of evolutionary changes over time?

  The fossil record.
• How does the fossil record provide evidence for evolution?

  It shows gradual changes in species over long periods of time.
• What is an example of how the fossil record provides evidence for evolution?

  It shows a series of horse fossils from small, multi-toed ancestors to larger, single-toed modern horses.
• How does the fossil record support the theory of evolution?

  It shows gradual changes in species over long periods of time.