All tree leaves have an outer layer called the epidermis, which can also be used in the identification process. This leaf "skin" always has a waxy cover called the cuticle and varies in thickness.

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Molecular evolution is the area of evolutionary biology that studies evolutionary change at the level of the DNA sequence. It includes the study of rates of sequence change, relative importance of ...

Experimental evolution articles from across Nature Portfolio Experimental evolution is the use of laboratory or controlled field manipulations to investigate evolutionary processes. It usually ...