Science-- there's something for everyone

Monday, October 21, 2013

A tale of two tails

What’s a bird to do if his flight-approved, aerodynamic tail isn’t showy enough to attract the ladies? Have two tails of course. Anyway, that seems to be how the Early Cretaceous bird Jeholornis solved this problem. Scientists led by Jingmai O’Connor of the Chinese Academy of Sciences discovered that Jeholornis had two functional tails.

Before I continue, I want to make one thing clear. We’re not talking about two separate strings of vertebrae. If you remove all the feathers, Jeholornis had a normal-looking skeleton with a single long vertebral tail. However, once you put the feathers back on, you get two distinct tufts of feathers at each end of that vertebral trail that most likely served very different purposes.


Reconstruction of the plumage of Jeholornis. (Scale bar: 5 cm.)
DOI: 10.1073/pnas.1316979110.


In modern birds, the last few vertebrae are fused into a solid structure called the ‘pygostyle’. The flight feathers of a bird’s tail (rectrices) are attached to the pygostyle. Jeholornis had a broad fan of feathers at the base of its backbone, similar to that seen on modern birds, but unlike all known birds, those feathers are not attached to a pygostyle. The authors suspect that this may be a feature that is unique to this species. This first ‘tail’ no doubt assisted the animal in flight. 

The second tail is composed of a feathery frond at the end of the vertebral column. This showy spread of feathers might not have hindered the bird in flight, but it was probably primarily ornamental. The researchers do not know whether it was present in both sexes or only one.


A prehistoric bird with two tails.
A reconstruction of a two-tailed 120-million-year-old Jeholornis. Illustration courtesy Aijuan Shi.




















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.




1 comment:

  1. HERPES VIRUS CURE

    Am here to appreciate Dr OJOGUN for using his herbal medicine to cure my Herpes virus. since 3 years now I have been living with this virus and it has been giving me challenges, I was so perplexed cause i have been taking several drugs to be cured but all of my effort was in vain,one morning i was browsing through the internet then i saw several testimonies about Dr. OJOGUN curing people from Herpes virus and immediately i contacted Dr. OJOGUN on his email: drojogunherbalmedicine@gmail.com, i told him about my troubles and he told me that i must be cured, gave me some instructions and which i rightly followed. so he prepared a herbal medicine for me and sent it to me which i used for 2 weeks and everything was like a dream to me and my Herpes virus was totally gone, why don't you contact him today and be free from your diseases because he is very good and honest Doctor. contact him via email; drojogunherbalmedicine@gmail.com or whatsApp him on +2347059015454

    ReplyDelete