Final answer:
Genetic tests enable the discovery of cryptic species by identifying genetic differences in populations that appear similar, thereby helping to resolve taxonomic uncertainties and reveal distinct lineages with varying life histories or invasion patterns.Option 2 is the correct answer.
Step-by-step explanation:
Genetic tests are a good way to discover cryptic species because grouping similar genotypes can reveal populations that do not or cannot interbreed. When a molecular approach, like DNA barcoding, is used, it can show significant molecular divergence among populations that are morphologically similar. This aids in resolving uncertainties of taxonomic identification and may reveal non-native cryptic species crucial in understanding their unique life history traits or invasion histories.
By utilizing genetic analysis tools such as DNA sequencing, researchers can differentiate organisms at the genetic level even when there's a scarcity of diagnostic physical traits. For example, taxa that appeared to be a single worldwide invasive species have turned out to be composed of several cryptic lineages upon genetic investigation, indicating different sister-species or sub-species. Thus, genetic testing provides a sophisticated means of species identification that surpasses morphological assessments, which may overlook cryptic diversity.