Onions, wheat and amoebae have more genes and more DNA than we do. Amphibians such as frogs and salamanders have genome sizes that range over two orders of magnitude, with some salamander genomes being 40 times larger than our own, and some frogs being less than a third of our size. If we had to sum up the architectural constraints on genomes in a single phrase, it would have to be ‘anything goes’.
