Two of Haeckel's other ideas about the evolution of development have fared better than recapitulation: he argued in the 1870s that changes in the timing (heterochrony) and changes in the positioning within the body (heterotopy) of aspects of embryonic development would drive evolution by changing the shape of a descendant's body compared to an ancestor's.
As outras dúas ideas de Haeckel sobre a evolución do desenvolvemento foilles mellor: argumentou na década de 1870 que os cambios temporais na aparición (heterocronía) e a posición no corpo (heterotopía) de aspectos do desenvolvemento embrionario impulsarían a evolución ao cambiar a forma do corpo dun descendente en comparación co dun devanceiro.