Final answer:
Genetic tests aid in discovering cryptic species by grouping genotypes to reveal non-interbreeding populations, which is crucial since cryptic species look identical but are genetically distinct.
Step-by-step explanation:
Genetic tests are a good way to discover cryptic species because grouping similar genotypes might reveal populations that do not or cannot interbreed. Cryptic species are groups of species that look identical but are genetically distinct; they can be especially challenging to differentiate based solely on morphology. Genetic tests, such as DNA barcoding and sequencing, allow researchers to detect these differences at the genetic level. By analyzing specific regions of DNA, scientists can determine if populations are exchanging genes or if they are independent and possibly evolving separately. Furthermore, genetic tools can help to resolve uncertainties of taxonomic identification and define management units based on genetic exchange.