Correlation of leaf and leaflet PSQA with mean annual precipitation and temperature.

Reflecting trends from the paleobotanical record, perimeter/(area)1/2 (PSQA) values correlate with mean annual temperature and precipitation levels from the point-of-origin of accessions. Leaf PSQA values correlate to a higher degree with precipitation than leaflet PSQA values, which correlate more highly with temperature in S. pimpinellifolium accessions. The data may suggest that leaf complexity and leaflet serration are indicators of precipitation and temperature, respectively, and species-specific adaptation with respect to S. pimpinellifolium. *p<0.05, **p<0.01, ***p<0.001.