Old Genes, New Tricks
For decades, scientists have understood that the process of evolution involves changes in protein-coding genes: mutations can change a gene's instructions, making it code for a protein with a slightly different function.
The modification of gene switches provides another avenue for evolutionary change. Often just a few base pairs long, switches regulate the timing, location, and level of protein expressionwithout affecting the protein itself. Small changes to switches can produce dramatic outcomes.
The evolution of new physical structures requires new genes.
Evolution frequently reuses old genes in new ways.
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