A Galapagos tortoise.
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Photo by KellyFishy CC BY-NC-ND 2.0.
A Galapagos tortoise.

A Tale of Two Turtles

If London’s Natural History Museum held hide-and-seek contests, Charles Darwin’s pet tortoise would be a champion. The naturalist’s carapaced companion, plucked from the Galapagos and brought all the way back to England, managed to remain hidden in the museum’s collections for over 170 years. Not that the credit can really go to the reptile. Darwin’s tortoise died long ago. The chelonian’s crypsis had more to do with misdirection and rumor.

Henry Nicholls recounted the story for the Guardian on the 205th anniversary of Charles Darwin’s birth. During the famous voyage of the Beagle, Nicholls pointed out, several tortoises were spared from the dinner table and made the return voyage with the crew. Among the tortoises was one that Darwin called his own and that had been scooped up from James Island, now known as Santiago.

What became of Darwin’s tortoise? The most popular hypothesis was that the shuffling reptile grew up to be Harriet, a giant tortoise that lived as the Australia Zoo in Queensland until she died in 2006. To think that there was a living link to the most important journey in Darwin’s life! But, citing research by Paul Chambers, Nicholls noted that Harriet couldn’t be the tortoise in question, particularly because Galapagos tortoises have distinctive shell anatomy and Harriet’s showed her to belong to a population never visited by the Beagle.

A stroke of curatorial luck finally revealed Darwin’s pet. In March of 2009, Nicholls reported, reptile collections manager Colin McCarthy was searching for some of Darwin’s historic specimens in the Natural History Museum’s Zoology Dry Storeroom No. 1. There, among the unlabeled specimens, was an old stuffed tortoise with “James” inscribed into the bottom shell. A long paper trail of collections reports confirmed McCarthy’s suspicions, and also showed how an early choice  not to record Darwin’s name along with the specimen allowed the reptile to seem like just another young and unremarkable tortoise. At long last, Darwin’s tortoise had been rediscovered!

Darwin’s tortoise – known by its accession number 1874.6.1.6 – isn’t the only reptile to resurface after being lost for decades. Two days before Nicholls’ article, paleontologist Andy Farke recounted the discovery of a much, much older turtle that had to misfortune to get tangled up in 19th century church politics.

In 1857, twenty years after Darwin gave his pet tortoise to the Natural History Museum’s collections, a French priest uncovered the impressive shell of a prehistoric turtle among the strata of the Jura Mountains. From there, Farke writes, the priest passed the fossil along to Joseph Célestin Girod, the vicar general of the Saint-Claude diocese, and Girod let Swiss paleontologists François Jules Pictet de la Rive and Aloïs Humbert describe the turtle. Upon examining the Jurassic shell, Pictet and Humbert designated the turtle as a new species – Emys etalloni.

Then the 150 million year old turtle got ensnared in a tug-of-war. Seeing that the turtle was scientifically significant, Farke noted, a bishop above the vicar suggested donating the fossil to a scientific society. The turtle got as far as the Natural History Museum of Besançon before Girod pointed out that he didn’t want to part with the turtle. Ancient Emys was returned to him, but no one knew what became of the fossil after Girod passed away in 1863.

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The shell of Plesiochelys etalloni, from Anquetin et al. 2014. CC-BY.

Not all turtles that wander are lost, though. A century and a half after Girod’s death, Farke explained, paleontologists  Jérémy Anquetin​, Sylvie Deschamps, and Julien Claude noticed the storied shell in the collections of France’s Musée d’archéologie du Jura. Tracing the story back, the paleontologists found that Girod had sold the turtle to a private collector before his death, and the shell had stayed with the collector’s family for over a century. It wasn’t until 1994 that the family donated the fossil to the museum, and it was another decade still before paleontologists rediscovered the turtle.

Studied anew, Girod’s turtle allowed Anquetin, Deschamps, and Claude to determine that the fossil really was a distinct species – now known as Plesiochelys etalloni – and resolve some long-running uncertainties about the identities and relationships of Europe’s Jurassic turtles. But, much like Darwin’s pet tortoise, what Girod’s turtle can tell us about natural history is only one facet of why such tangled tales are so important.

On a purely superficial level, Darwin’s tortoise and Girod’s turtle are individual representations of their respective species. Dig a little deeper into what’s left of them and you can draw out clues about their lives, but, as many naturalists did for decades, both can easily be overlooked as mundane tidbits of natural history held in an abundant rank and file of similar specimens. What makes them truly special, however, are the stories they record about human history.

While Darwin battled seasickness and started to wonder why animals of different Galapagos islands seemed distinct from each other, his pet tortoise was there with him. That’s something we can only appreciate in hindsight – as Nicholls suggested, perhaps Darwin’s name wasn’t attached to his donated tortoise because no one had any idea how revolutionary the young naturalist would later become. And through Girot’s turtle we can now look back to the curious relationship between religion and science in the 19th century.

The same sense of human history and fascination surrounds innumerable other specimens – from dinosaur bones to pressed flowers – saved in museums around the world. The hands that touch them and the minds that wonder about them might not leave any permanent marks like the inscription of “James” on Darwin’s tortoise, yet by studying and arguing over these curious representations of the wild we intertwine human history with nature’s mysteries.

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I was ecstatic when I got to see the holotype skull of Ceratosaurus. Photo by Brian Switek.

Museums are stewards stories. There’s no more powerful reminder of this than having the chance to wander natural history collections with those attuned to the tales hidden among racks of critters in jars and rows of bones cradled in plaster jackets.

Last weekend, on a trip to the National Museum of Natural History, I was lucky enough to take a behind-the-scenes tour with curator of vertebrate paleontology Hans-Dieter Sues and artist Ray Troll. The three of us ran the other visitors in the group ragged as we pinballed around the collections, enthusing over delicate fossils and carefully touching the same remains that so inspired researchers such as embattled “Bone Wars” paleontologist Othniel Charles Marsh and Charles Gilmore, who was brought in by the institution to work on Marsh’s classic specimens. And, really, it’s difficult to stand in front of a Triceratops skull that has been sawed cleanly and half and not marvel at such a symbol of Deep Time and scientific curiosity.

But the impetus for writing this post goes back to one very special fossil. When I looked down at the gorgeous, charcoal-colored holotype skull of Ceratosaurus – a dinosaur I went so far as to have tattooed on my arm – I was absolutely thrilled to even momentarily connect with over 130 years of efforts to understand the past and our place in nature. Like Darwin’s tortoise and Girod’s turtle, the dinosaur is now more than a piece of petrified bone. We’ve made it something more – a monument to our wonder at the natural world.

[A note on the title. While I distinguish between turtles and tortoises in this post, for the sake of alliteration and the literary reference I decided to use “turtle” in the more general sense for the title.

Top image by KellyFishy on Flickr. (License.)]