Extinct Tortoises Alive

Attention: open in a new window. PDFPrintE-mail

Extinct tortoises alive claim scientists on Galapagos Islands, according to reports in BBC News 9 January 2012 and ABC News in Science 10 Jan 2012. The different shaped shells of the giant tortoises on the various Galapagos Islands is considered to be one of the observations that inspired Darwin to develop his theory of evolution. According to the BBC, “The animals are thought to have colonised the archipelago through floating from the shores of South America. Colonies on each island remained relatively isolated from each other, and so evolved in subtly different directions.” A giant tortoise named Chelonoidis elephantopus is known to have lived on the island of Floreana in the Galapagos Islands when Charles Darwin visited the islands in 1835, but is believed to have died out soon after this. C. elephantopus had a distinctive saddleback shaped shell, while the tortoises on neighbouring islands had a dome shaped shell. Recently, scientists studying Galapagos tortoises around a site named Volcano Wolf on Isabella Island had noted what Gisella Caccone called a mystery: “you could find domed shells, you could find saddlebacks, and anything in between."

Now scientists conducting a new study of the DNA from a related species, C. becki , claim C. elephantopus could still be alive and breeding with other tortoises on Isabella Island. The researchers collected samples from 200 tortoises and found 84 of them had C. elephantopus DNA in their genomes. The scientists compared the DNA of living tortoises with museum specimens and claim "the newly sampled individuals can only be explained if one of their two parents were C. elephantopus." As 30 of the tortoises are less than15 years old, and the animals can live for over a century, the scientists suspect pure bred C. elephantopus parents could still be alive. Ryan Garrick, one the researchers commented: "If found, these purebred C. elephantopus individuals could constitute core founders of a captive breeding program directed towards resurrecting this species."


Editorial Comment: What a reminder that the definition of ‘species’ is really a human construct. The tortoises on Floreana Island did have a different shell shape, but it is proving to be simply a variation within kind, as evidenced by the finding of the varying shaped shells around Volcano Wolf. The theory that the tortoises arrived on the islands on floating rafts of vegetation is probably correct, but the original populations that colonised each island have not “evolved in subtly different directions”. Inbreeding within a limited gene pool has simply reinforced the characteristics that were already present in the original populations on each island.

In Darwin’s day each group of island tortoises had little opportunity to breed with other tortoises as the Galapagos Islands were rarely visited by man, and tortoises (as opposed to turtles) do not cross seas easily. This meant that each subgroup had distinctive shell shapes and patterns, but were still of the same kind. This perpetuation of distinctive characteristics over generations happens in island populations of any animal where the gene pool in limited. Since then they have been carried all over the world on board ships, as well to other islands, and have happily interbred with others of their own kind, and no doubt improved the gene pool with some re-mixing.

There is no need for a captive breeding programme as they are obviously breeding, and they don’t need resurrecting because they are not dead. They should be left in peace to do what comes naturally, not be kept in artificial captivity to prop up evolutionists’ stories. These are not the only creatures on the Galapagos Islands that are classified as different species but are really one kind. Recent research has confirmed the famous “Darwin’s finches” are really just variations within kind and provide no evidence for evolution.

Evidence News 2 February 2012