So, as you all know, species lived in particular ecological niches and particular environments, and the pressures of those environments selected which changes, through random mutation in species, were going to be preserved.
Como todos vocês sabem, as espécies viviam em nichos ecológicos específicos e ambientes particulares, e as pressões desses ambientes selecionaram as mudanças que seriam preservadas através de mutações aleatórias nas espécies.