Divergence in male sexual odor signal and genetics across populations of the red mason bee, <i>Osmia bicornis</i>, in Europe - Fig 1

<p><b>Gas chromatogram of three male <i>Osmia bicornis</i> antennal extracts: A (England), B (Denmark) and C (Germany)</b>. Chemical separations were performed on a non-polar DB-5 mass spectrometry (MS) column. Peaks were quantified using GC analyses and identified using GC/MS and by comparison of gas chromatographic retention times with those of authentic reference samples. Numbered peaks correspond to the compounds listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193153#pone.0193153.t001" target="_blank">Table 1</a>. Unnumbered peaks were contaminants.