Edyta Zielinska | Mar 10, 2010 | 2 min read
Arctic reindeer, which live most of the year in 24-hour darkness or daylight, may lack an internal clock common to most organisms, according to research published online today (March 11) in __Current Biology.__ ReindeerImage: Per Harald Olsen/WikimediaThe study found no evidence of cyclic changes in reindeer gene expression, consistent with behavioral evidence that the arctic animals do not rely on such daily rhythms. But the fact that the researchers only investigated two clock genes in one