‘Venom’ – a manipulative weapon for overcoming the victim’s protective barriers

I would like to congratulate Jenner et al. for their excellent job in redefining the contested term ‘animal venom’ into: ‘Venoms manipulate the physiological functioning of recipients to produce extended phenotypes that are beneficial to the venom producer and detrimental to its victim‘ [1]. Their new focus on the ‘extended phenotype’ overcomes some restrictions of previous definitions [2,3] resulting in the inclusion of zootoxic, hematophagous, phytophagous, phytotoxic, and sexual venoms under the venom umbrella [1]. To still keep the term compact and manageable, their venom definition retained the need for penetrating the victim’s external protective barrier by specialised morphological structures stating that ‘venoms are delivered through the infliction of a wound, while poisons are not’ [1]. In line with previous definitions, ingested or inhaled toxins are considered poisons [1., 2., 3.]. While I largely agree with their new definition, I’d like to suggest an alternative definition that clarifies conflicting aspects around spat or sprayed venoms and that expands the term ‘venom’ beyond animals to include zootoxic plant venoms like those of the Australian stinging tree Dendrocnide excelsa [4]. Venoms evolve from conflicts between organisms, and they feature a variety of mechanisms to overcome the resulting challenges. Mechanical injury is not the only possible route for toxins to penetrate the victim’s protective barriers; hence my amended venom definition, which follows, also includes delivery by chemical means: