The rediscovery of Charles Darwin’s long-lost Galapagos tortoise - via Herp Digest

The Guardian 1/12/14---It’s Charles Darwin’s birthday (he would be 205 today) and Galapagos Day (the islands were claimed by Ecuador 182 years ago), the perfect cue for a story about a special reptilian pet

For photo of tortoise go to http://www.theguardian.com/science/animal-magic/2014/feb/12/celebrity-pet-discovery-darwin-tortoise

Darwin's pet tortoise, collected from Santiago in the Galapagos during the voyage of the Beagle. When in the Galapagos, Charles Darwin and his Beagle chums ate a couple of dozen giant tortoises, tossing their empty shells over board en route to Tahiti. But in his Narrative of the voyage, captain Robert FitzRoy made it clear that a few small tortoises had survived. “Several were brought alive to England,” he wrote.

For FitzRoy had scooped up two tiny tortoises from Espanola (an island in the south of the archipelago) and took enough interest in them to monitor their growth during the home stretch of the voyage: “a small one grew three-eighths of an inch, in length, in three months; and another grew two inches in length in one year.”

There were at least two other small Galapagos tortoises on board, as noted by Darwin himself. One – “Covington’s little Tortoise” – had been brought from Floreana by his assistant Syms Covington. The other – “Mine from James” – seems to have been Darwin’s, collected during his stay on Santiago (or James Island, as it was then known). It’s rather nice to imagine it plodding round his cramped cabin as he set about cataloguing his Galapagos specimens.

A drawing of Darwin and an adult tortoise on Santiago, as imagined by Meredith Nugent. Photograph: Charles Darwin: His Life and Work (1891)

But where did Darwin’s pet tortoise end up? It’s a fabulous question that has given rise to a fabulous myth, one that is documented in detail in A Sheltered Life by Paul Chambers. In short, Darwin’s tortoise is supposed to have become Harriet, a giant tortoise that lived at the Australia Zoo in Queensland until her death in 2006 (allegedly transported down under by John Clements Wickham, the Beagle’s first lieutenant under FitzRoy).

On its website, the Australia Zoo still claims “Harriet was collected from the Galapagos Islands in 1835 by Sir Charles Darwin when she was just the size of a dinner plate.” This, as Chambers clearly demonstrated in his book and in a follow-up feature in New Scientist, is simply wishful thinking. He gave many compelling reasons, including the fact that Harriet appears to have come from Santa Cruz (a Galapagos island not visited by the Beagle). Unfortunately though, Chambers was not able to track down Darwin’s tortoise to another location, which would have definitively debunked the Harriet fable. A few years after Chambers’ investigation, however, Darwin’s tortoise – missing for over 170 years – finally turned up at the Natural History Museum in London.

I emailed Colin McCarthy, former collections manager for reptiles, amphibians and fish at the museum, to ask him to elaborate. “I can pinpoint my discovery to late March 2009,” he says. Over the course of the preceding year, McCarthy had been busy preparing a list of reptiles and amphibians collected by Darwin during the course of the Beagle voyage. When it came to the tortoises he’d brought back, there were some loose ends, “specimens that had been listed in early registers but not in later catalogues.”

Down in the basement of the museum in the now-famous Zoology Dry Storeroom No. 1, McCarthy was going through some unlabeled specimens when he came across a small tortoise with its plastron (undercarriage) loosely wired to its carapace (shell). “Hinging the plastron back I noticed ‘James’” etched into the surface, he says. “I could hardly believe my eyes and immediately put the specimen back on the shelf in case I dropped it in my excitement!”

Also scratched on the inside of the plastron, hidden from McCarthy’s predecessors, there was the registration number: 37.8.13.1. Armed with this information, he combed back through the zoology register and there, logged on 13 August 1837, were two tortoises “presented by Charles Darwin Esq”, one corresponding to Darwin’s pet from Santiago (James) and the other to Covington’s pet from Floreana (Charles).

From this entry, it emerges that Darwin visited South Kensington in August 1837 and presented these two tortoises to John Edward Gray, then assistant keeper of zoology at the museum. By then, Darwin had figured out that each of the Galapagos Islands probably had a suite of allied yet subtly different species. FitzRoy had already deposited his two Espanola tortoises with Gray earlier in the year and Darwin was hoping that there might be some clear differences in tortoise morphology from one island to the next.

Unfortunately, juvenile tortoises – even ones from different islands – look pretty similar. “The specimens,” Darwin conceded, “were young ones; and probably owing to this cause, neither Mr Gray nor myself could find in them any specific differences,” he wrote in the beefed-up second edition of his Journal of Researches published in 1845.

If Darwin’s tortoise has been in the Natural History Museum all along, how come nobody noticed? Well they did and they didn’t. Writing in Chelonian Conservation and Biology in 2010, McCarthy (and a colleague Aaron Bauer) were able to identify both Darwin and Covington’s tortoises in a succession of museum catalogues produced by a succession of curators, ultimately being given a new accession number in 1874 (1874.6.1.6). Crucially, however, Darwin’s name never appears alongside these entries. In 1844, for instance, Gray knocked up a Catalogue of Tortoises, Crocodiles and Amphibians in the collection. Darwin’s and Covington’s tortoises are there but this is all it says:

f. Young, 7 inches. Nuchal plate none.

g. Young, 6 inches. Nuchal plate none, feet bad.

Based on a recent publication of the growth rate of young tortoises in captivity, a 7-inch carapace suggests that Darwin’s tortoise would have been just over three years old at the time of death. Assuming it passed away in 1837, prompting Darwin to take it along to the museum, it seems reasonable to assume it hatched out in Galapagos in 1834 (or thereabouts).

It might seem odd that Gray didn’t stick Darwin’s name into the catalogue. Then again why would he? Remember, this was a full 15 years before Darwin published On the Origin of Species. There was no way that Gray could have anticipated the celebrity that Darwin would become, less still how much interest this small and unassuming reptile would generate 170 years later.

I’m thrilled it survives. It can be seen on a tour of the Spirit Collection.

Happy birthday Chuck!

Tale ends

There are several loose ends to this story that remain to be cleared up. If you can help solve any of these outstanding mysteries, please leave a comment or send me a message on Twitter @WayOfThePanda.

• Where is Covington’s tortoise? As it came from Floreana, it belongs to a species that has been extinct since the middle of the 19th century. When McCarthy looked for it at the Natural History Museum (and it was a very thorough look) it was not there. “I would love for it to turn up one day but sadly that is very unlikely,” he says. “It may be that its condition had deteriorated further and that, in the assumed absence of any data, it was discarded,” he and Bauer wrote in their 2010 paper. If Covington’s tortoise survives, it would need to meet this description: shell six inches long; likely to have “37.8.13.2 Charles” scratched onto the plastron; feet “bad”.
• Where’s the DNA study of Harriet? According to Paul Chambers, it was carried out by a biologist called Scott Davis but I can’t see that he ever published it. There might be something mentioned in Scott Thomson, Steve Irwin, Terri Irwin (1996) Harriet: La Tortuga de Galapagos. Reptilia 2 (4): 46-49. Can anyone get me a copy?
• If Harriet is not Darwin’s tortoise, how did she get to Australia? I fancy that Wickham could well have had something to do with her. What if he’d collected some tortoises too? After the Beagle returned to England, the ship set off again for Australia with Wickham as its skipper. Chambers could find no evidence of tortoises on board this voyage or why Wickham would have left them in Australia. But then again?
• There are almost certainly other Beagle tortoises yet to be discovered. Chambers came across an interesting letter from Darwin to Albert Günther in 1874 in which Darwin had the “vague remembrance that specimens were given to the Military Institution in Whitehall.” They wouldn’t have been thrown out, surely?
• Chambers also mentioned “an ex-curator” at Down House (Darwin’s home), who had heard that Beagle tortoises had been given to the Bishop of Llandaff. Anyone?

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