Tanystrophenus longobardicus fossils


Tanystropheus longobardicus has formed many adaptations throughout evolution, but one very important adaptation to note is its long neck. This adaptation has given this animal its nickname “giraffe-reptile”. According to engineers estimates T. longobardicus’ neck length was at the longest permissible under the laws of physics (Haines and Chambers, 2006). This characteristic neck of the T. longobardicus extended more than twice it's body length. Most would think that with such a long neck comes more vertebrae, but in this case that is untrue. T. longobardicus’ necks contain only 11 vertebrae. Because of the few number of joints within the neck, the vertical mobility that T. longobardicus had was limited. This limited mobility was also a factor of its peculiar ribs (Dal Sasso and Brillante, 2004). These ribs were very long, filiform, and grouped in bundles extending posterior to the attached vertebrae and passed the next vertebrae. The reason for such a long neck is still a mystery to paleontologists.

Fossil of Tanystropheus longobardicus skull and neck (along with ribs; fine lines along neck/vertebrae).

Tanystropheus longobardicus would have had to make up for the weight and gravitational pull their extremely long neck placed upon the rest of their body. According to the fossil evidence collected at the Valle Serrata locality (Switzerland), the first fossil where skin and soft tissues can be described, it is believed that the T. longobardicus had a larger mass of tissues present in the caudal (towards the tail) region on the body, moving the center of mass of the animal posteriorly, and helping balance the weight of the neck, even when raised out of the horizontal plane or out of water (Renesto, 2005).

Scientists argue that, as a result of an extraordinarily long neck that could be elevated only slightly above the horizontal, Tanystropheus longobardicus would have had very restricted movement on land (Tschanz, 1988). Depending on the lifestyle of the T. longobardicus, adaptations in reproduction would be needed for aquatic life versus terrestrial life.  T. longobardicus might have only come on land to lay eggs, or perhaps not at all (Rieppel et al. 2010). A hypothesis suggests that they supported a brood pouch of some kind. If terrestrial life was unfit for these animals, it could be speculated that females retained the eggs or embryos within an internal pouch and gave birth to live young at sea. However there is no possible explanation of heterotopic elements at this time (Fraser, 2006).

To learn more about Tanystropheus longobardicus' reproduction theories, check out our Reproduction page!