Charles Darwin's impressions of New Zealand and Australia, and insights into his illness and his developing ideas on evolution.

Charles Darwin visited New Zealand in December 1835, and Australia from January until March 1836, on the return portion of his voyage around the world in HMS Beagle. Despite the shortness of these visits, he retained an interest in these countries throughout his life, maintaining correspondence and receiving many biological specimens. His experiences in these places influenced his thinking on evolution, particularly on the evolution of man. Aspects of his health recorded during this part of the voyage support a new hypothesis for the diagnosis of the illness that Darwin endured for most of his life.