Deep homology and the origins of evolutionary novelty.
Do new anatomical structures arise de novo, or do they evolve from pre-existing structures? Advances in developmental genetics, palaeontology and evolutionary developmental biology have recently shed light on the origins of some of the structures that most intrigued Charles Darwin, including animal eyes, tetrapod limbs and giant beetle horns. In each case, structures arose by the modification of pre-existing genetic regulatory circuits established in early metazoans. The deep homology of generative processes and cell-type specification mechanisms in animal development has provided the foundation for the independent evolution of a great variety of structures.
Shubin
Neil
N
Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, Illinois 60637, USA. nshubin@uchicago.edu
Tabin
Cliff
C
Carroll
Sean
S
D000818:Animals; D005075:Biological Evolution; D001517:Coleoptera / Q000033:anatomy & histology; D005121:Extremities / Q000033:anatomy & histology / Q000502:physiology*; D005123:Eye / Q000033:anatomy & histology; D005786:Gene Expression Regulation; D006733:Horns / Q000033:anatomy & histology / Q000502:physiology*; D009799:Ocular Physiological Phenomena; D014157:Transcription Factors / Q000502:physiology
D014157:Transcription Factors