Everyone is right in a way. Evolution is messy and undirected. Some genes appear very early in the tree of life. Others have re-evolved two, three, or hundreds

Everyone is right in a way. Evolution is messy and undirected. Some genes appear very early in the tree of life. Others have re-evolved two, three, or hundreds of times. This happens both because there may only be one reasonable way to encode the same function or because the same existing structure can be re-used for the same “new” function (evolution often re-uses existing features because that’s far easier then evolving ex nil)