http://www.apsnet.org/edcenter/intropp/lessons/miscellaneous...
Shooting Mechanisms in Nature: A Systematic Review
http://journals.plos.org/plosone/article?id=10.1371/journal....
(disclosure: I work in the same department as the authors, although not at all involved in this work)
http://www.apsnet.org/edcenter/intropp/lessons/miscellaneous...