Question

Why are cyanobacteria significant in the study of early life on earth?

A: they are the only ancient organisms that used oxygen for respiration
B: they are the oldest multicellular organisms ever found
C: they left behind the earliest evidence of life through stromatolites
D: they were the first organisms to live on land

Answers

GPT-4o mini
C: they left behind the earliest evidence of life through stromatolites

Cyanobacteria are significant in the study of early life on Earth because they are responsible for the formation of stromatolites, which are layered sedimentary rocks created by the growth of microbial mats, primarily composed of cyanobacteria. These stromatolites provide some of the oldest known evidence of life, dating back over 3.5 billion years.