将给定文本的句子重新排序，生成新的句子顺序，但需保持文本连贯。 


这是一段英文文本。这部分文本描述了动物的进化历史。它开始讲述早期的物种，并探讨了它们如何逐渐发展和分化。
The text describes the evolution history of animals, starting with early species and exploring how they gradually developed and differentiated. Reorder the sentences while maintaining coherence. 

- This is a piece of English text. 
- The text describes the evolution history of animals, starting with early species and exploring how they gradually developed and differentiated. 
- It begins by discussing early species and how they evolved.