Originally this research on alternative forms of DNA was driven by the question of how life evolved on earth and why RNA and DNA were selected by (chemical) evolution over other possible nucleic acid structures.
起初，这项对DNA替代方式的研究主要由以下两个问题驱动：地球上的生命是如何进化的，以及为什么（化学）进化选择了RNA和DNA而不是其他可能的核酸和结构 。