Why do genetic studies provide deep information about living beings?
Genetic studies provide deep information because every living cell contains genetic material (DNA), which carries the instructions for its growth and function. By comparing organisms at the DNA level, scientists can study similarities in inherited features that external traits might not reveal.
Organisms with similar DNA are considered to have a common ancestry. Studying genetics helps reveal that microscopic life forms are far more diverse than previously believed. This deep information has even aided in modifying classification systems, such as Carl Woese's three domain system.
Explanation
The textbook context highlights that DNA carries the fundamental instructions for an organism's growth and function, making it a deep and precise level for comparison. It further explains that genetic similarity indicates common ancestry and reveals the vast diversity of microscopic life, which ultimately helped scientists like Carl Woese modify classification systems.