Under nature the process will be far more complicated than is represented in the diagram; for the groups will have been more numerous; they will have endured for extremely unequal lengths of time, and will have been modified in various degrees.
Naturan prozesu hau askoz korapilatsuagoa izanen da, diagraman irudikatzen dena baino; izan ere, taldeak gehiago izanen ziren, denbora tarte zeharo ezberdinetan biziraunen zuten eta maila ezberdinetan aldatuko ziren.