Recent geophysical data as well as theoretical models suggest that, to the contrary, both oxygen and carbon dioxide concentrations have changed dramatically during defining periods of metazoan evolution.
Recentes datos xeofísicos e modelos teóricos suxiren que, ao contrario, tanto as concentracións de oxíxeno coma as de dióxido de carbono cambiaron drasticamente durante períodos definidos da evolución dos metazoos.