The Unfolding Story of Life's Change

Mutation and Genetic Variation

At the core of evolution lies genetic variation. This arises primarily through random mutations – changes in DNA sequences – which introduce new traits into populations. These mutations are not directed; they occur spontaneously.

The rate of mutation varies across species and even within different regions of an organism’s genome. Higher mutation rates generally correlate with faster evolutionary potential, though excessive mutation can be detrimental.

ΔG = kT + ln(β), where ΔG is the change in free energy due to mutation, k is Boltzmann's constant, T is absolute temperature, and β represents the rate of a specific mutation.

Natural Selection: The Driving Force

Natural selection acts on this existing genetic variation. Individuals with traits that are better suited to their environment – advantageous mutations – are more likely to survive and reproduce.

This process, known as differential survival and reproduction, leads to an increase in the frequency of beneficial alleles within a population over generations. This is the essence of adaptation.

Fitness (w) = (Number of Offspring) / (Initial Number of Individuals)

Adaptation and Phenotypic Change

The changes in allele frequencies resulting from natural selection are reflected in the phenotypic characteristics of a population – its observable traits. These adaptations can be morphological, physiological, or behavioral.

Within our simulation, you’ll observe how populations ‘learn’ to optimize their performance based on environmental conditions, demonstrating a tangible manifestation of evolutionary adaptation.

ΔP = (w * dp) * dt, where ΔP is the change in phenotype, w is fitness, dp is the differential in allele frequency, and dt is the time step.

Speciation and Evolutionary Divergence

Over vast timescales, natural selection can lead to reproductive isolation between populations – a key step in speciation. This occurs when genetic differences become so significant that individuals from different groups can no longer successfully interbreed.

Our simulation allows you to explore how diverging selective pressures can drive distinct evolutionary trajectories for interacting populations, showcasing the fundamental processes of diversification.

Frequently asked questions

Try it live

Everything above runs in your browser — open SPH Fluid and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.