演化发生 meaning in English

genetic inception

Paleontological studies showed that modern avian groups probably first appeared in the paleocene and experienced an explosive radiation in the early cenozoic
古生物学研究表明，现生鸟类的最早出现是在古新世，而爆发性辐射演化发生在新生代早期。
In addition , no back mutation to obtain a maximal complexity ( i . e . - resistant and sensitive species coexistence ) or original ecology ( i . e . original - lysogen ) for the evolution occurs
而且，逆反应变异回原有菌相而成对噬菌体敏感及阻抗菌相共存之最大分歧度或回归至起始单一对噬茵体敏感菌相并未曾演化发生。