|Reconstruction of the plumage of Jeholornis. (Scale bar: 5 cm.)|
At first, I thought it was slightly misleading to say that Jeholornis had two tails, rather than a single tail containing two distinct features. However, these two parts of its anatomy not only served different functions, but were also attached to the body in different ways. So, I’m sticking with my title.
Jingmai O’Connor, Xiaoli Wang, Corwin Sullivan, Xiaoting Zheng, Pablo Tubaro, Xiaomei Zhang, & Zhonghe Zhou (2013). Unique caudal plumage of Jeholornis and complex tail evolution in early birds Proceedings of the National Academy of Sciences of the United States of America DOI: 10.1073/pnas.1316979110.