15 citations,
July 2004 in “Journal of morphology” Monotreme hair structure and protein distribution are similar to other mammals, but their inner root sheath cornifies differently, suggesting a unique evolution from reptile skin.
86 citations,
April 2009 in “Journal of anatomy” Hard skin features like scales, feathers, and hair evolved through specific protein changes in different animal groups.
51 citations,
September 2012 in “Biomacromolecules” Disulfide bonds make keratin in hair stronger and tougher.
127 citations,
January 2015 in “Journal of Biological Rhythms” The skin's internal clock affects healing, cancer risk, aging, immunity, and hair growth, and disruptions can harm skin health.
36 citations,
November 2019 in “Molecular biology and evolution” Cysteine-rich keratins evolved independently in mammals, reptiles, and birds for hard skin structures like hair, claws, and feathers.