Evolutionary Biology Background

Before we can model evolution in a computer system, we need to understand evolution as a concept. The first part of today’s class is a discussion on evolution and evolutionary processes so that we can start to understand how those processes can be modeled in a computer.

Evolution has three key ingredients:

  • Heritability. Traits have to be able to be passed down to offspring.
  • Variation/Mutation. Traits have to be able to change over time in the population in some way.
  • Selection. There has to be some external pressure on the system driving a change in proportions

In today’s class we’ll talk about the general concepts behind evolutionary systems, and also touch on heritability.

Discussion

Define Evolution

What is evolution? What isn’t evolution? Work within your small groups to come up with a complete yet concise definition of evolution. Take into account that evolution is not just something that acts on natural systems; it is a process and can be broadly applied outside of biology.

Evolutionary Misconceptions

Each of your groups will be assigned one of the following misconceptions; you’ll answer these two questions:

  • How can we correct this misconception?
  • Where do you think this misconception comes from? That is, why might people think this?
  1. Evolution results in progress; organisms improve or become better through evolution.
  2. Evolution is the result of organisms trying to adapt to their environments.
  3. The fittest organisms in a population are the healthiest, strongest, fastest, largest, etc.
  4. Evolution is about the “survival of the fittest”: the best organisms reproduce to create the next generation.

Inheritance

How are traits passed down in evolution, if not through the “best” or through attempts to make improvements?

Traits are passed down via a transfer of information. In this case, information is stored in the pattern of molecules of DNA. This information is then transcribed into a secondary alphabet (RNA), then into functional components (proteins).

the central dogma of biology

Think: What parts of this process do you think are necessary for the concept of inheritance as it relates to evolution? Which parts do you think are artefacts of biological systems?

If we wanted to model this process computationally, what might be a good place to start?