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How is reptile molting different from the continuous shedding of mammal skin?

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A pangolin walks through grass with a blue circle around it and the word endangered written in white across the image. — Integument The pangolin is the only mammal in the world covered in scales.

In biology, the process of shedding skin differs significantly between reptiles and mammals due to how their epidermal cells are replaced.

In mammals, skin renewal is a continuous process of cell division and exfoliation, where individual cells are shed from the surface as new ones are produced in the deeper layers. In contrast, many reptiles—particularly snakes and lizards—undergo a periodic, hormonally controlled process known as ecdysis.123

Rather than shedding individual cells, these reptiles form a complete new epidermal surface beneath the old, cornified layer. Once this new skin is functional, the entire old layer is sloughed off, either in a single sheet (as in snakes) or in patches (as in many lizards). While some reptiles, such as crocodiles and turtles, exhibit continuous cell division and exfoliation similar to mammals, the distinct, cyclical molting of snakes and lizards is a specialized adaptation that allows them to replace their entire outer covering at once.132