Evolutionary Biology

  1. What is evolutionary biology? Evolutionary biology is the study of how living things change over time. It looks at how different species come to be, how they adapt to their surroundings, and why there are so many different types of living things on Earth.

  2. What is life? Life refers to things that can grow, reproduce, use energy, and respond to their environment. All living things are made up of tiny units called cells. Inside these cells is a special molecule called DNA, which contains instructions for building and running the organism. Sections of DNA that have specific instructions are called genes.

  3. What is evolution? Evolution is the process by which living things change over many generations. This happens because some traits help organisms survive and reproduce better in their environment. These helpful traits get passed down to future generations more often.

    There are several ways evolution happens:

    • Natural selection: Organisms with traits that help them survive and reproduce better tend to pass these traits to their offspring.
    • Mutation: Sometimes, random changes happen in an organism’s DNA. These changes can create new traits.
    • Genetic drift: By chance, some traits might become more or less common in a population, especially in small groups.
    • Gene flow: When different populations mix and breed, they share genetic material, which can change how both populations evolve.

  4. What is a species? A species is a group of living things that can breed with each other and have offspring that can also breed. When groups of the same species get separated and can’t breed with each other anymore, they might eventually become different species.

  5. What drives evolution? Several factors push evolution forward:
    • Environmental pressure: The conditions in which organisms live affect which traits are helpful for survival.
    • Reproductive success: Traits that help organisms have more offspring become more common over time.
    • Adaptation: Over time, organisms become better suited to their environment through changes in their body structure, behavior, or internal processes.

  6. The role of time: Evolution usually happens very slowly. Small changes add up over many, many generations to create big differences between species.

  7. The fossil record and genetic evidence: Fossils are the remains or traces of ancient life. They help us understand how living things have changed over millions of years. Modern genetics also helps us understand evolution by letting us compare the DNA of different species to see how closely related they are.

  8. How evolutionary biology works - the scientific method: Scientists study evolution using a step-by-step process:
    1. They observe differences between organisms.
    2. They come up with ideas to explain these differences.
    3. They test their ideas through experiments or by studying fossils and DNA.
    4. If an idea is supported by lots of evidence, it becomes part of the broader theory of evolution.
    5. Some ideas in evolution are so well-supported that they’re considered laws or principles, like the law of natural selection.

In summary, evolutionary biology studies how living things change over time because of differences in their genes and the challenges they face in their surroundings.