What are dyrosaurs?

March 11th, 2013
Posted by: Whiting,Evan T

Dyrosaurs* (or more specifically dyrosaurid crocodyliforms) are relatives of modern crocodylians that superficially look very similar to their living cousins. Dyrosaurs first appeared in the Late Cretaceous Period during the Mesozoic Era (the so-called “age of dinosaurs”) about 70 million years ago, and persisted into the Cenozoic Era until approximately 35 million years ago. Most dyrosaurs were marine animals with long snouts used for catching fish in ancient oceans. However, some of the Cerrejón dyrosaurs differ from this typical anatomical and ecological pattern, possessing much blunter snouts used for eating prey items such as turtles and living entirely in freshwater. These unique members of the dyrosaur family are characterized by shortened snouts and a decreased (or completely absent) reliance on saltwater environments, which could help explain why this group survived the great K-T Extinction 65 million years ago that wiped out all non-avian dinosaurs and a number of other prominent reptile groups on land and in the seas. Ongoing research will hopefully shed more light on the unique paleoecologies and adaptations of the Cerrejón dyrosaurs, so keep your eyes peeled for new and exciting studies on these incredible animals!

*Note the spelling of this group (DYRosaurs) compared to a very different group of animals with a similar name (DRYosaurs). Dryosaurs are plant-eating ornithischian dinosaurs that lived during the Late Jurassic Period of the Mesozoic Era and are completely unrelated to dyrosaurs. A tiny misspelling can therefore make a BIG difference, as switching just two letters around in this case can mean the difference between a crocodile relative and a small, bipedal dinosaur!

If you’d like to learn more about dyrosaurs, here are a few suggested scientific publications worth checking out:

Jouve, S., B. Bouya, and M. Amaghzaz. 2008. A long‐snouted dyrosaurid (Crocodyliformes, Mesoeucrocodylia) from the Paleocene of Morocco: Phylogenetic and palaeobiogeographic implications. Palaeontology 51(2):281-294.

Hastings, A. K., J. I. Bloch, E. A. Cadena, and C. A. Jaramillo. 2010. A new small short-snouted dyrosaurid (Crocodylomorpha, Mesoeucrocodylia) from the Paleocene of Northeastern Colombia. Journal of Vertebrate Paleontology 30(1):139-162.

Hastings, A. K., J. I. Bloch, and C. A. Jaramillo. 2011. A new longirostrine dyrosaurid (Crocodylomorpha, Mesoeucrocodylia) from the Paleocene of north‐eastern Colombia: biogeographic and behavioural implications for New‐World Dyrosauridae. Palaeontology 54(5):1095-1116.

Welcome to the Prep Lab!

February 16th, 2013
Posted by: Harrington,Arianna R

What do we do in the Titanoboa: Monster Snake prep lab?

The prep lab is the place where numerous fossils of the largest known snake, Titanoboa cerrejonensis, are being prepared. (Occasionally, we will be working on a dyrosaurid crocodile from a neighboring locality in Colombia—please see our next blog post for more information on these animals!)

Currently, all Titanoboa fossils that we are preparing are those associated with one individual—in fact, the most complete one found to date. This means that all of the ribs and vertebrae that we are prepping in the lab are thought to have belonged to one big snake!

We are focusing our attention on preparing parts of this specific individual Titanoboa because its relative completeness makes it very scientifically interesting. Whole fossil skeletons are rarely preserved and paleontologists gain more information when more  complete specimens are discovered.


typical workstation

Above: a typical work space of a prep worker in the Titanoboa prep lab


How do we prepare Titanoboa fossils?

Fossils of Titanoboa cerrejonensis all come from one of the largest coal mines in the world in Cerrejón, Colombia. In fact, the scientific name Titanoboa cerrejonensis very aptly means “titanic boa from Cerrejón.”

Fossils from the Cerrejón coal mine are sandwiched between layers of shale-like grey sediment that is interspersed with layers of charcoal and sulfur. As much as possible of this surrounding material (generally called the matrix) must be removed from the fossil. This is because fossils that have not been cleaned and prepared properly can deteriorate over time. For example, fossils from the Cerrejón coal mine have a tendency to grow pyritic crystals (called ‘pyrite disease’) if they are not prepared or stored properly. These destructive crystals can grow as a result of being exposed to high levels of humidity.

This is the same reason why acetone (a chemical found in nail polish remover) is used instead of water when we prepare fossils of Titanoboa. Acetone is gently brushed onto fossils to scrub them free of dirt, charcoal, and sulfur. Water is not used because it does not evaporate as quickly as acetone does, and excess moisture on a Cerrejón fossil will accelerate the growth of damaging crystals.

We also use dissecting microscopes, dental picks, carbide tips, glue, and forceps when we prepare Cerrejón fossils. The fossils are fairly fragile and sometimes, it is very difficult to tell what is fossil and what is matrix with merely the naked eye. Therefore, much care is taken in the preparation of these fossils. The goal of the prep lab is to thoroughly clean fossils of Titanoboa so that they will be preserved and available for study for years to come.


What happens to the fossils after we prepare them?

Titanoboa fossils that we prepare will be used by researchers at many institutions for scientific study. They will be stored at the Florida Museum of Natural History while research is being conducted in the United States. After this is done, they will be returned to their country of origin, Colombia.


Where can I learn more about Titanoboa and the prep lab?

Come visit us to learn more about how we prepare Titanoboa fossils! Our lab is staffed at all times during exhibit hours, and we are more than happy to answer any questions.

You can also learn more about the discovery, biology, and world Titanoboa in the rest of the exhibit, as well as by watching the Titanoboa: Monster Snake documentary video available on the Smithsonian Channel website, and through the scientific publication below:


Head, J. J., J. I. Bloch, A. K. Hastings, J. R. Bourque, E. A. Cadena, F. A. Herrera, P. D. Polly, and C. A. Jaramillo. 2009. Giant boid snake from the Paleocene neotropics reveals hotter past equatorial temperatures. Nature, 457: 715-717.


We hope to see you soon and that you enjoy your visit!