Pete Oxford / Buttress roots (size compared with man). Manu NP, Peru, South America

Nigel Cattlin / Flat backed millepede (Polydesmus angustus) damage to young Sugar beet (Beta vulgaris). Damaged tap root in comparison to normal undamaged tap root. England, UK.

Alain Dragesco-Joffe / Striped hyena (Hyaena hyaena) footprints, showing typical larger rouder track of the front feet compared to back feet. Azaouak, Sahara Desert, Niger, .

Franco Banfi / Polar bear (Ursus maritimus) footprints compared to print from human shoe, Spitsbergen, Svalbard, Norway, Arctic Ocean.

Julian Hume / Comparison of Giant Scimitar-billed Nukupu'u (Hemignathus vorpalis) (below), compared with adult males of Akiapola'au (Hemignathus munroi) (Extant, endangered) (above) and Kauai Nukupu'u (Hemignathus...

Julian Hume / Scaled head studies of extinct Hawaiian Geese compared with Nene (Branta sandvicensis) (centre). Clockwise from top left: Giant hawaiian goose (Branta sp), Maui nui moa-nalo (Thambetochen chauliodous)...

Lorraine Bennery / One euro coin compared with the size of a Praying mantis (Ameles decolor) female eating male after mating, Vaucluse, France, September.

Paul D Stewart / Historical illustration of humans and primates from Naturliche Schopfungsgeschichte (2nd edition) by Ernst Haeckel, 1870. Haekel was a leading proponent of what is now described as scientific racism a...

Paul D Stewart / Historical illustration of humans from Naturliche Schopfungsgeschichte (2nd edition) by Ernst Haeckel, 1870. Haekel was a leading proponent of what is now described as scientific racism and believed i...

Paul D Stewart / Historical illustration of primates from Naturliche Schopfungsgeschichte (2nd edition) by Ernst Haeckel, 1870. Haekel was a leading proponent of what is now described as scientific racism and believed...

Frederique Olivier / Colony with female Emperor penguin (Aptenodytes forsteri) returning from sea, note the size difference compared to the males with eggs, Antarctica, July.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) colony with females returning from sea, note the size difference compared to the males incubating eggs, Antarctica, July.