Next, you’ll build a simulation based on what you think will happen because of natural selection. Here are two considerations:

Some individuals with harmful characteristics can still successfully reproduce, but they have an overall lower chance of doing so compared to organisms with neutral or beneficial traits.
Natural selection may affect distribution of traits. It’s possible that harmful traits could eventually disappear from the gene pool.
Don’t worry about precise population numbers. Based on your understanding of natural selection, you’ll be modeling only one scientifically plausible trend that can occur. There are several correct variations of this diagram. You’ll explain the justification for your choices in part E.

Assume that these plants have a life expectancy of about one year, but the rate of reproduction keeps their population consistently around 2,500 organisms. Using the same elements you used in part C, draw simulations for year 5 and year 10. Clearly label each simulation.

Explanation:

Key Points

Natural selection can cause microevolution (change in allele frequencies), with fitness-increasing alleles becoming more common in the population.

Fitness is a measure of reproductive success (how many offspring an organism leaves in the next generation, relative to others in the group).

Natural selection can act on traits determined by alternative alleles of a single gene, or on polygenic traits (traits determined by many genes).

Natural selection on traits determined by multiple genes may take the form of stabilizing selection, directional selection, or disruptive selection.

Introduction

We've already met a few different mechanisms of evolution. Genetic drift, migration, mutation...the list goes on. All of these mechanisms can make a population evolve, or change in its genetic makeup over generations.

But there's one mechanism of evolution that's a bit more famous than the others, and that's natural selection. What makes natural selection so special? Out of all the mechanisms of evolution, it's the only one that can consistently make populations adapted, or better-suited for their environment, over time.