Titanoboa cerrejonensis – A Very Bad Thermometer

Article by: Adam Manning
Edited by: Jack Wood, J. D. Dixon, and Lewis Haller

A Titanoboa skeletal mount. Available at: https://www.extinctanimals.org/titanoboa.htm.

Name: Titanoboa cerrejonensis
Name Meaning: Titanic boa from Cerrejón
Age: 60-58 million years ago, Paleocene
Diet: Carnivore
Size: 13 m in length
Weight: 1135 kg
Location: Colombia, South America

The largest snake alive today is the Giant Anaconda, measuring an average of 5 m in length, and weighing just under 250 kg. However, it has nothing on the nightmare fuel of Titanoboa cerrejonensis, the largest snake ever discovered.

This amazing find came after a geology student visiting Cerrejón on a field trip found several plant fossils in several pieces of sandstone, the first clues of the presence of the rainforest that developed there 60 million years ago. Over time, many familiar rainforest plants, like banana, chocolate, and coconuts, were found in the area, as well as many large vertebrates, like giant crocodile-like animals and huge turtles to name a few. Then, of course, they found the enormous vertebrae of Titanoboa, and remarkably, three skull fragments. Snake skulls are made of delicate bones so they rarely fossilise, and the skull finds provide a unique insight into Titanoboa’s morphology and evolutionary history.

Related to modern Boa Constrictors, Titanoboa lived in the wet tropical rainforest that grew in what is now Cerrejón, Colombia. It likely lived in both the water and on land. Being able to exploit both environments meant that it had access to more varied prey types, and could avoid causing damage to its own body, due to its huge size, by letting the water support its weight. It is unclear if Titanoboa was a constrictor, using its own body to asphyxiate its prey like its modern relatives, or if it successfully predated in a different way.

A Boa imperator. It is thought the extinct Titanoboa would have had a similar appearance. Available at: https://abcnews4.com/news/local/boa-constrictor-released-in-s-carolina-park.

What might be most interesting about Titanoboa’s discovery are the implications of the palaeoclimate of the area at the time. Poikilothermic, or cold-blooded, animals like snakes rely on the outside environment to regulate their body temperature, and therefore their maximum size is often limited by the temperature of their environment. Based on the colossal size of Titanoboa, a study authored by Head et al. suggests there would need to be a minimum mean annual temperature of 30 – 34 OC for the snake to survive, 3.8 – 7.2 °C above the modern value.

However, many studies have argued against this, suggesting that Titanoboa is an inappropriate palaeothermometer because it would have been able to have some control over its internal body temperature with its behaviour. Furthermore, others have argued that Head et al.’s findings were overestimating the palaeotemperature, and another study stated the extinct large lizard Varanus (Megalania) prisca would be 3 to 4 times longer than predicted by the largest living lizard today if the same approach used with Titanoboa was applied. This suggests that large modern lizards are rare today due to the function of competition with other mammalian carnivores, not because of the function of modern temperatures.

This highlights how Titanaboa likely came to evolve. After the K-PG mass extinction at the end of the Cretaceous Period, many ecological niches were left open for the surviving types of life, especially the roles of large predators in the ecosystem. So with little competition from other animals, Titanoboa was able to grow to huge sizes to prey upon the other animals it shared its habitat with.

On the surface, Titanoboa cerrejonensis may just seem like another terrifying monster not to worry too much about, as it is long dead now. Yet, remarkable finds like it show life’s extraordinary ability to bounce back after mass extinctions, and can tell palaeontologists about the palaeoenvironment that these animals lived in.

Image References
[1] A Titanoboa skeletal mount. Available at: https://www.extinctanimals.org/titanoboa.htm.
[2] A Boa imperator. It is thought the extinct Titanoboa would have had a similar appearance. Available at: https://abcnews4.com/news/local/boa-constrictor-released-in-s-carolina-park.

Information References and Further Sources
[1] DeLong, W. (2018/2019). ‘Titanoboa Was The 50-Foot Prehistoric Snake Of Nightmares’, All That’s Interesting. Available at: https://allthatsinteresting.com/titanoboa-snake. Accessed 14th October 2019.
[2] Denny, M. W., Lockwood, B. L., and Somero, G. N. (2009). Can the giant snake predict palaeoclimate?, Nature, 460 (7255), pp. E3-E4. Available at: https://www.nature.com/articles/nature08224. Accessed 14th October 2019.
[3] Extinct Animals. (2019). ‘Titanoboa’. Available at: https://www.extinctanimals.org/titanoboa.htm. Accessed 14th October 2019.
[4] Gugliotta, G. (2012). ‘How Titanoboa, the 40-Foot-Long Snake, Was Found’, Smithsonian Magazine. Available at: https://www.smithsonianmag.com/science-nature/how-titanoboa-the-40-foot-long-snake-was-found-115791429/. Accessed 14th October 2019.
[5] Head, J. J., Bloch, J. I., Hastings, A. K., Bourque, J. R., Cadena, E. A., Herrera, F. A., Polly, P. D., and Jaramillo, C. A. (2009). Giant boid snake from the Palaeocene neotropics reveals hotter past equatorial temperatures, Nature, 457 (7230), pp. 715-717. doi: Available at: https://www.nature.com/articles/nature07671. Accessed 14th October 2019.
[6] Makarieva, A. M., Gorshkov, V. G., and Li, B-L. (2009). Re-calibrating the snake palaeothermometer, Nature, 460 (7255), pp. E2-E3. Available at: https://www.nature.com/articles/nature08223. Accessed 14th October 2019.
[7] Sniderman, J. M. K. (2009). Biased reptilian palaeothermometer?, Nature, 460 (7255), pp. E1-E2. Available at: https://www.nature.com/articles/nature08222#ref4. Accessed 14th October 2019.