What is a defining characteristic of a species?

A defining characteristic of a species is the ability to interbreed and produce fertile offspring. This criterion is central to the biological species concept, which defines a species as a group of organisms that can reproduce with one another in nature and produce viable, fertile offspring. This reproductive capability ensures that the gene pool of the species remains cohesive and allows for the passing of genetic traits through generations, contributing to the overall stability and function of the ecosystem.

The interbreeding aspect is crucial because it distinguishes members of one species from those of different species, particularly in cases where species may share similar habitats or physical traits. The successful reproduction leads to the continuation of the species through fertile progeny, which is vital for sustaining population numbers and maintaining biodiversity within ecosystems.