6 November 2013
When lights shine on an animal’s eyes at night, what color is reflected back to you?
For cats it’s green. For possums it’s red. For arctic reindeer, also known as caribou (Rangifer tarandus), it depends on the time of year!
The tapetum lucidum in reindeer’s eyes changes color to cope with the bright light of summer and the low light of winter. In summer reindeer eyes reflect gold, in winter they look blue.
This cool effect was discovered by a team from University College London and University of Tromsø, Norway thanks to funding from BBSRC (Biotechnology and Biological Sciences Research Council).
The video shows what they look like. Read more about the study here at Phys.org.
(video from BBSRC via phys.org)
p.s. They have two other amazing traits:
- Reindeer can see ultraviolet light,
- They have no circadian rhythm.