Humans develop their ability to see in color while in the womb.
The radiant colors of a sunset, or the detailed, vibrant colors of a butterfly are all able to be detected if our color vision has developed properly before we were even born. While researchers knew that cells that detect blue light are the first to appear and then cells that respond to green red are next, it was not possible to study the subsequent development of color sensing cells until recently.
Scientists were able to replicate the process of how color vision develops by growing immature human retinal cells into functioning organoids. Details of the discover were published in the journal Science
Researchers utilized information gained from animal research that suggested thyroid hormone was involved in development of color-sensing cells. The researchers added thyroid hormone to the retinal cells during their development. The process took years and additional experiments but scientists were able to confirm that thyroid hormone is the trigger for the emergence of color vision. Researcher are hopeful that additional research will lead to new treatments for retinal diseases.