Discussion
We quantified natural genetic variation in circadian period among and
within 30 populations of B. stricta sampled across a
heterogeneous landscape in the central Rocky Mountains. With multiple
maternal families representing each population, we found that genetic
diversity was significant and of comparable magnitude among and within
populations. Spatial proximity explained only a small proportion of
among-population patterns of diversity, but elevation-related variation
in the trait suggested environment-driven genetic differentiation in the
region.