MattKing
Moderator
I saw this, and thought of the regular contributors in this sub-forum! 
https://www.washingtonpost.com/climate-environment/2023/12/18/reindeer-eyes-blue-winter/
An excerpt - in case the article is behind a pay-wall.
A new study suggests that the hoofed mammalsâ unique eyes, which glow a vivid blue when illuminated in colder months, may be a result of the species evolving so they can more easily find food during dark Arctic winters.
âReindeer have just an amazing visual system,â said Nathaniel Dominy, the studyâs lead author and a professor of anthropology at Dartmouth College. âItâs unlike any other mammal we know about.â
Similar to other animals, like cats or deer, the ungulates have light-enhancing tissue in their eyes, known as tapetum lucidum. But in reindeer, the luminescence changes color from a golden color in the summer to blue in the winter.
Scientists have long puzzled over that trait, along with the reindeerâs ability to see light in the ultraviolet spectrum. The layer of tissue is typically found in nocturnal animals because it increases their ability to see in dim light, but reindeer are out and about during the day.
Dominy and researchers from the University of St Andrewsâ School of Psychology and Neuroscience say they have one possible explanation: Reindeer vision has evolved, in part, to help the animals survive dark winters by improving their ability to find their favorite food when conditions arenât favorable.
Best of the season to all!
https://www.washingtonpost.com/climate-environment/2023/12/18/reindeer-eyes-blue-winter/
An excerpt - in case the article is behind a pay-wall.
Why reindeer eyes shine blue in the winter
Rudolphâs red nose may have gone down in history, but research says it was probably his shining blue eyes â a common trait among reindeer â that helped keep him and the rest of Santaâs herd nourished.A new study suggests that the hoofed mammalsâ unique eyes, which glow a vivid blue when illuminated in colder months, may be a result of the species evolving so they can more easily find food during dark Arctic winters.
âReindeer have just an amazing visual system,â said Nathaniel Dominy, the studyâs lead author and a professor of anthropology at Dartmouth College. âItâs unlike any other mammal we know about.â
Similar to other animals, like cats or deer, the ungulates have light-enhancing tissue in their eyes, known as tapetum lucidum. But in reindeer, the luminescence changes color from a golden color in the summer to blue in the winter.
Scientists have long puzzled over that trait, along with the reindeerâs ability to see light in the ultraviolet spectrum. The layer of tissue is typically found in nocturnal animals because it increases their ability to see in dim light, but reindeer are out and about during the day.
Dominy and researchers from the University of St Andrewsâ School of Psychology and Neuroscience say they have one possible explanation: Reindeer vision has evolved, in part, to help the animals survive dark winters by improving their ability to find their favorite food when conditions arenât favorable.
Best of the season to all!
