Rockhopper penguin Northern Rockhopper; and the "Eudyptes chrysocome", the Southern Rockhopper. They are separated by their locations of breeding. There are four other species in the genus "Eudyptes": "E. pachyrhynchus", "E. robustus", "E. chrysolophus", and "E. schlegeli". The three subspecies of the rockhopper penguin are believed to have split up because of latitude and watermasses rather than because of geographic distances. Research suggests that during the early Pleistocene, the Southern Ocean was cold and rockhopper populations from the Atlantic and Indian Oceans remained undifferentiated and lived in the same watermass. The mid-Pleistocene climatic transition was associated with the southward migration of frontal
What Bird is That? What Bird is That? What Bird is That? A Guide to the Birds of Australia is a book first published in 1931 by Angus & Robertson in Sydney. Authored and illustrated by Neville William Cayley, it was Australia’s first fully illustrated national field guide to birds, a function it served alone for nearly 40 years. In 1960 it was rated the all-time best seller in Australian natural history. "What Bird Is That?" was originally published in octavo format (239 x 158 mm), containing 340 pages bound in green buckram, with a dust jacket illustrated with a painting of a laughing