What's your favorite color?
If you said pink, you're in good company -- it's been in style for more than a billion years, sort of.
Scientists from the Australian National University and overseas say they have discovered the oldest colors in the geological record.
Think "bright pink" -- 1.1 billion-year-old bright pink pigments to be exact.
Researchers extracted the ancient pink pigments from rocks deep beneath the Sahara desert in Africa.
"The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished," said Dr Gueneli from the ANU Research School of Earth Sciences.
The fossils range from blood red to deep purple in their concentrated form, and bright pink when diluted, according to the study.
ANU led the research with support from Geoscience Australia and researchers in the United States and Japan.
The research is published in PNAS.
Study: Pink is the world's oldest color