Final answer:
Bacterial and archaeal species should be identified using DNA and rRNA sequencing techniques to determine their genetic differences and evolutionary relationships.
Step-by-step explanation:
Bacterial and archaeal species should be identified using various scientific methods and tools. One of the important approaches is genetic analysis. Konstantinidis and Tiedje (2005) emphasize the use of DNA and rRNA sequencing to identify and classify these microorganisms. These techniques provide insights into the genetic differences and evolutionary relationships between bacterial and archaeal species, enabling their accurate identification and classification.