The fish also showed anatomical changes, including stronger chests and an elongation below the head, which could be interpreted as the beginnings of a neck.

Whereas the neurological criteria depend mainly upon muscle tone, the physical ones rely on anatomical changes.

He also described the anatomical changes that place in liver cirrhosis and malaria perniciosa.

As a scientist, his excellent descriptions of morphologic details gave credence to the idea that zoological evolution can be learned through its anatomical changes.

These anatomical changes lead, among others, to changes in voice production, breathing, and olfaction.