This week science lost a celebrity of the most unusual sort. Known to people around the world as Lonesome George, he was recognized as the last living member of his subspecies, the Pinta giant tortoise (Geochelone abingdoni) one of the giant tortoises of the Galapagos Islands. These slow and steady creatures hold a special place in science history. Observing differences between the giant tortoise populations of different Galapagos Islands helped a young Charles Darwin develop his theory of evolution.
George’s death was unexpected. Giant tortoises typically live to 200 years or more, so at an estimated age of 100, George should have been in the prime of life. He was hardly lonely either. He had shared his coral with several different females over the years; all placed there in the hopes that there might be some little George hatchlings to carry on in their father’s foot steps. Unfortunately no fertile eggs were ever produced, and George died the last of his kind.
Or was he….
No end-of-a-species story is complete without an upstart challenger. In 2007 a letter was published in Current Biology that announced the identification of at lease one individual on Volcano Wolf on neighboring Isobela Island who shared Pinta ancestry. Although this individual had a mitochondrial DNA (mtDNA) haplotype much like a different subspecies, Geochelone hoodensi, analysis of ten nuclear microsatellite loci showed strong G. abingdoni ancestry and assigned the individual to the Pinta population.
So all hope may not be lost for the giant tortoise of Pinta Island. There may be descendants still living in the mixed population of Isobela Island. Perhaps poor Lonesome George wasn’t as all alone as we supposed.
After five years with the taxidermists, Lonesome George has returned to his home in the Galapagos National Park. You can read more here: https://www.theguardian.com/science/animal-magic/2017/feb/17/welcome-home-lonesome-george-giant-tortoise-returns-to-galapagos
- Russello, M. A., et al. (2007) Lonesome George is not alone among Galápagos tortoises. Curr. Biol. 17, R317–18.