Supplementary Video 1. Agkistrodon contortrix in Kentucky engaged in food-induced combat

Supplemental Video 3. Northern cottonmouths in North Carolina engaged in food-induced male-male combat

Four Agkistrodon conanti interact including engaging in food-induced male-male combat

Supplementary material 2 (Video). Changes in sailfish breathing from gill pump ventilation to ram ventilation

Supplementary material 1 (Video). “Pose” cleaning-request behavior of sailfish and response of marlin suckers

Warriors in Combat

Warriors in Combat

Supplementary material 3 (Video). “Cleaning-like” behavior of marlin suckers toward a sailfish

Supplementary material 1 (Video). The aggressive behavior of marked worker toward an attached worker

Comic Figures Engaged In Various Tasks

Kumagai and Atsumori in Combat

Video 1 Bobcat Body Rubbing

Bone marrow changes in adjuvant-induced and collagen-induced arthritis : IL-1 and IL-6 activity and abnormal myelopoiesis

Glibenclamide prevents coronary vasodilation induced by β[1]-adrenoceptor stimulation in dogs

[Village scene in Japan showing people engaged in various activities]

Food safari. Series 2, episode 1, Japanese food safari

Japanese coolies engaged in the work of blasting rock

New Food Products in Japan

Caspase-independent apoptosis induced by differentiation-inducing factor of D.discoideum in INS-1 cells

No. 1 (ichi), from the series "Women Engaged in the Sericulture Industry (Joshoku kaiko tewaza-gusa)"

Supplementary material 2 (Video). The escape behavior of marked worker from an attached worker

[Battle scene - soldiers engaged in close fighting on a battlefield]

Extensive cell death in thymocytes in colon 26-induced cachectic mice

Glomerular alterations in uranyl acetate-induced acute renal failure in rabbits

A second example of Agkistrodon piscivorus in North Carolina engaging in combat