The "DNA World Hypothesis" suggests that early life forms were primarily based on DNA as the main molecule for storing genetic information. This idea posits that DNA played a crucial role in the evolution of life, allowing organisms to replicate and pass on traits to future generations. According to this hypothesis, RNA may have initially acted as a precursor to DNA, but over time, DNA became the dominant genetic material due to its stability and efficiency in encoding information. This shift is thought to have been a key factor in the complexity and diversity of life on Earth.