He gained international recognition for his study of comparative anatomy and experiments with reptiles, particularly observing their colour patterns in relation to their nerve supply.

On return, he made numerous contributions to dermatology, including the definition of keratoacanthoma, the distinction between pemphigus and pemphigoid and descriptions of melanocytes and malignant melanoma.

[2] With the encouragement and support from Geoffrey Dowling, he developed an interest in the skin and Whimster soon became closely associated with Arthur Rook,[3] working on the histopathology of keratoacanthoma[3] and the distinction between the bullous diseases pemphigoid and pemphigus.

[3][5] Whimster gained international recognition for his work on comparative anatomy and experiments with reptiles, particularly observing their colour patterns in relation to their nerve supply.

[2] His statement that "some invisible intersegmental boundaries, whose existence we have been taught to expect by comparative anatomy and embryology, are only revealed by disease"[6] stemmed from Whimster's interest in the causes of linear or sharply demarcated rashes unexplained by external stimuli.