The roots of biodiversity: How proteins differ across species

To better understand what drives biological diversity on Earth, scientists have historically looked at genetic differences between species. But this only provides part of the picture. The traits of a particular species are not merely the result of its genes but also the proteins those genes code for. Understanding the differences between species' proteomes—or all of the proteins that can be expressed—is, therefore, as important as understanding differences between genomes. 

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