David Tipling / Brown hare (Lepus europaeus) boxing in spring North Norfolk, England, UK. May.

Dietmar Nill / Two European hares (Lepus europaeus) boxing in a snow covered field, Germany, March.

Ingo Arndt / Eastern grey kangaroos sparring {Macropus giganteus} Australia

Donald M. Jones / Dall's Sheep (Ovis dalli) rams posturing, central Alaska

Donald M. Jones / White-tailed Deer (Odocoileus virginianus) bucks sparring, western Montana

Andy Rouse / Mountain hares (Lepus timidus) boxing in snow, Scotland, UK, December.

Erlend Haarberg / Mountain hares (Lepus timidus) boxing, Vauldalen, Sor-Trondelag, Norway, May.

Richard Du Toit / Blue Wildebeest (Connochaetes taurinus) males sparring, Kgalagadi Transfrontier Park, South Africa

Anup Shah / Topi (Damaliscus lunatus jimela) two males sparring, with another approaching, Masai Mara National Reserve, Kenya. March

Christophe Courteau / Two African Buffalo {Sincerus caffer} bulls sparring, Okavango Delta, Botswana.

Anup Shah / African elephants (Loxodonta africana) sparring, Masai Mara National Reserve, Kenya, August

Andy Rouse / Agile wallabies (Macropus agilis) sparring and fighting, Bamarru Plains, Northern Territories, Australia