Phylogenetic distributions of behaviors used in male-male combat in snakes, with black boxes representing the recorded presence of a behavior and white boxes representing the absence of a record of the behavior.

<p>See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107528#pone-0107528-t001" target="_blank">Table 1</a> for references. On the chart on the right, the heavy horizontal lines separate families and subfamilies. On the cladogram, white circles represent families, gray oblongs represent subfamilies, and the gray square is a tribe. Suprageneric taxonomy follows reference <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107528#pone.0107528-Pyron1" target="_blank">[9]</a>. Taxonomic abbreviations: B = Boidae. b = Boinae. C = Colubridae. c = Colubrinae. cr = Crotalinae. d = Dipsadinae. E = Elapidae. L = Lamprophiidae. l = Lamprophiinae. la = Lampropeltini. n = Natricinae. P = Pythoninae. ps = Psammophiinae. px = Pseudoxyrhophiinae. V = Viperidae. v = Viperinae. For abbreviations of behavioral characters, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107528#pone-0107528-t002" target="_blank">Table 2</a>.