Limb diversity and digit reduction in reptilian evolution
The study of morphological rules, or trends, offered classical biologists the opportunity to address the mechanisms underlying the evolution of anatomical designs. Regularities in evolution suggested that common functional or developmental rules governed the transformation of structures. Parallelism is one such example.
University of Chicago Press
Digit loss; Morphology; Adaptation
Shapiro, M. D., Shubin, N. H., & Downs, J. P. (2006). Limb diversity and digit reduction in reptilian evolution, in Hall, B. K. (eds.). Fins into limbs: evolution, development, and transportation. 225-44.