What is a deme?

A deme refers to a local population of organisms that are capable of interbreeding and have limited gene flow with other populations. This means that within a deme, individuals are more likely to reproduce with one another than with individuals from distant populations, allowing for the accumulation of specific genetic traits or adaptations that are suited to their local environment.

This concept is crucial in understanding population genetics and speciation, as it highlights how populations can diverge genetically over time due to restricted gene flow. The limited exchange of genetic material with neighboring demes can lead to differences in allele frequencies, which may ultimately contribute to the process of speciation.

Looking at other options, a large population with extensive gene flow describes a scenario where genetic material freely mixes, which would not create the distinct genetic characteristics typical of a deme. A type of species that can interbreed in a specific environment emphasizes the broader concept of species but does not capture the specific local population dynamics that define a deme. Lastly, a genetic mutation prevalent in a specific area speaks to individual genetic changes rather than the population-level interactions that characterize a deme. Thus, identifying a deme as a local population with limited gene flow neatly encapsulates the essential features that differentiate it from broader population concepts.