Male-male fighting of Harbor seals 1

Male-male fighting of Harbor seals 2

Male-male fighting of northern elephant seals

Male-male agonistic behavior of Sitticus penicillatus (1)

Male-male competition of Japanese scorpionfly

Male-male fighting behavior of the seed bug, Togo hemipterus

Male-male agonistic behavior of Carrhotus xanthogramma

Male-male fighting in a butterfly

Male-male agonistic behavior of Sitticus penicillatus (2)

Male-male agonistic behavior of Sitticus penicillatus (3)

Male-male competition in Uca arcuata

Male-male combat of Otton frogs

Male-male combat of Otton frogs II

Female fighting of Dorcus rectus rectus

The re-invasion behavior of Japanese scorpionfly males that lost the male-male competition

Female-female fighting behavior of the Japanese horned beetle

Territorial contest in male Chrysozephyrus smaragdinus

The hostility action of Harbor seal

Fighting Thomson's gazelle

Agonistic interaction of Kajika frog (Buergeria buergeri) 2: escalated fighting

Major cheliped use in owner male during male-male contest of hermit crab

オイカワの雄間闘争

セボシタビラの雄間闘争

アブラボテの雄間闘争

Male-male competition for eggs in the filefish Rudarius ercodes