Question: what are the four major eras and their dates?
Answer: Precambrian Time: 4.6 billion to 542 Million Years Ago. John Cancalosi / Getty Images. ... 
Paleozoic Era: 542 Million to 250 Million Years Ago. Jose A. ... 
Mesozoic Era: 250 Million to 65 Million Years Ago. Science Library / Getty Images. ... 
Cenozoic Era: 65 Million Years Ago to the Present.