Solvin Zankl / Gentoo Penguins {Pygoscelis papua} visible underwater in the surf line using the thrust of the breaking waves, Falkland Islands.

Tim MacMillan / John Downer Pr / Multiple exposure of flying Paradise tree snake showing how it forms a loop for maximum thrust as it lauches itself into air (Resolution restriction - image digitised from film, 'Weird Nature' tv seri...

Mark Moffett / Tarantula (Theraphosidae) moving away from Tarantula Hawk (Pepsis sp) which is about to thrust stinger into and stun the spider, California