Darwin, together with J. B. Lamarck, promoted a vision of a changing world, while upholding the idea that organisms evolved from a single root – a position held by Adam and Eve in the creationist worldview, and taken over in the modern era by the Last Universal Common Ancestor (LUCA). And from that remnant of the Biblical story of creation sprung the notion of a tree of life, alongside major concepts such as gradualism (the view that speciation does not occur abruptly) and the idea that minor selection pressures can, over time, have a profound effect on improved fitness.
达尔文与法国博物学家J.B.拉马克一道，一方面宣扬世界处于不断变化状态的观点，同时也坚信生物是由一个单一的根源进化而来——也就是创世论者世界观中亚当和夏娃所处的位置，并由当代的物种共同祖先（Last Universal Common Ancestor，LUCA）理论继承了下来。他们的理论包含了圣经造物故事中催生生命树这一概念的零散篇章，加上类似渐变论（gradualism，认为物种并非突然形成）这样的主要概念，还有微小的选择压力可以——随着时间推移——对物种的改良产生深刻影响的理论。