Crocodile Head Scales Are Not Developmental Units But Emerge from Physical Cracking

  title={Crocodile Head Scales Are Not Developmental Units But Emerge from Physical Cracking},
  author={Michel C. Milinkovitch and Liana Manukyan and Adrien Debry and Nicolas Di-Po{\"i} and Samuel Martin and Daljit Singh and Dominique Lambert and Matthias Zwicker},
  pages={78 - 81}
How the Crocodile Got Its Scales Mammalian hairs, avian feathers, and reptile scales differentiate and grow from genetically controlled units. Using three-dimensional (3D) computer graphics and computational biology to study scale generation, Milinkovitch et al. (p. 78, published online 29 November; see the cover) show that crocodilians' face and jaw scales do not follow this rule but emerge by physical cracking of the developing skin in a tension field. Thus, a crocodile's head scales are not… 
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