给出一篇文章并将其中的语言转化为简单易懂的词汇，使得学生也能够理解。


原始文章：“The theory of evolution by natural selection, first formulated in Darwin's book "On the Origin of Species" in 1859, is the process by which organisms change over time as a result of changes in heritable physical or behavioral traits. Changes that allow an organism to better adapt to its environment will help it survive and have more offspring.”
简化版：“进化论是由达尔文在1859年出版的《物种起源》一书中首次提出的理论，它是生物因遗传物理或行为特征的改变而随时间而变化的过程。这些变化让一个生物能够更好地适应环境，帮助它生存并拥有更多的后代。”