What concept describes evolutionary change over time based on DNA mutation rates?

The concept that describes evolutionary change over time based on DNA mutation rates is known as the molecular clock. This concept operates under the premise that changes in DNA sequences accumulate at relatively constant rates over time. By analyzing these mutations, scientists can estimate the time of divergence between species by using the genetic differences observed in contemporary organisms. This mechanism provides a way to quantify evolutionary time, lending insight into the relationships and timelines between different species based on genetic data.

In contrast, a phylogenetic tree is a diagram that represents the evolutionary relationships among various biological species based on similarities and differences in their physical or genetic characteristics; while it can incorporate molecular clock data, it does not specifically describe the process of measuring evolutionary change via mutation rates. Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time, focusing more on environmental factors rather than mutation rates. Genetic drift refers to the random fluctuations in allele frequencies within a population from one generation to another, which can lead to changes in a population’s genetic makeup but is not primarily concerned with the timing of evolutionary changes as measured by DNA mutations.