Queen Cleopatra and the mysterious snails of Volubilis

Author: Julián Monge Nájera, Ecologist and Photographer 

Windswept in the middle of a forgotten valley in North Africa, an ancient city bears the curious name of Volubilis. Volubilis exists thanks to a love story that almost everyone has heard of, that of Antony and Cleopatra. And its ruins are home to something that should not be there: a snail that seems to be made of marble.

In 45 BC the troops of Julius Caesar defeated the Numidian king Juba I. Juba committed suicide in Tunisia, but Julius Caesar took his young son to Rome, a little boy who would be in “preschool” if he lived in our times. Little Juba was not mistreated; on the contrary, he was treated as a noble and received the best education, and he spoke and wrote perfect Latin and Greek. Years passed, Julius Caesar was assassinated, and Cleopatra and Antony died, but they left behind a daughter named Cleopatra Selena II¹.

In 28 BC, in need of an ally in Africa, Emperor Octavius Augustus sent Juba II to reign in his father’s country, and there his story would be joined with that of a small snail. Accompanied by his wife Cleopatra Selena II, the wise Numidian king enlarged the ancient Carthaginian population of Volubilis and made it capital of the kingdom.

History tells us that he and Cleopatra Selena were wise sovereigns. Juba II wrote excellent books about archeology and Mediterranean history, as well as two zoological treatises, which were widely cited by Pliny the Elder¹. 

Years passed and the city was devastated by an earthquake in the 4th century, but among the stones and vegetation, one inhabitant survived, the Cernuella virgata² snails. 

In 28 BC, in need of an ally in Africa, Emperor Octavius Augustus sent Juba II to reign in his father’s country, and there his story would be joined with that of a small snail. 

But Cernuella virgata should not be there for a very simple reason: it is an European snail, not an African snail. 

How did it get there?

My hypothesis is that the snail’s arrival in Volubilis occurred in the 2nd century, when the local revolts forced Emperor Marcus Aurelius to send Roman troops and build a wall around the city³.

As in the 1990s, when Iraqi snails were detected in military equipment returning to the United States after Operation Desert Storm, Roman snails must have traveled attached to military equipment and other supplies carried by the Roman troops. This does not exclude the possibility that the Romans willingly took them as food, since these particular species of snail is still consumed in Spain, where the Romans stayed for centuries.

Ironically, most of what we know about this snail’s life we owe to Australian malacologists. Why?

Because just like it went to North Africa, Cernuella virgata reached Australia, where it has been an agricultural pest since the beginning of the 20th century. Thanks to this we know that it reproduces in time for baby snails to enjoy the good microclimate of the rainy season, that larger individuals lay more eggs, and that they normally stay in a restricted area⁴, equivalent to a human not moving in his life more than 3 km from their house. And yet they have come a long way in these two millennia!

Originally published  in Blog Biología Tropical: 15 july 2020

REFERENCIAS

¹ Roller, D. W. (2003). The World of Juba II and Kleopatra Selene. Reino Unido: Routledge.

² Hogan, C. M. (2007). Volubilis, The Megalithic Portal. Retrieved from https://www.megalithic.co.uk/article.php?sid=14906

³ Rogerson, B. (2010). Marrakesh, Fez and Rabat. Londres, Inglaterra: Cadogan Guides

⁴ Baker, G. H. (2008). The population dynamics of the mediterranean snails Cernuella virgata, Cochlicella acuta (Hygromiidae) and Theba pisana (Helicidae) in pasture–cereal rotations in South Australia: a 20-year study. Australian Journal of Experimental Agriculture, 48(12), 1514-1522.