To mark the 80th anniversary of the extinction of the thylacine, and to launch the 2016 season of remembrance for lost species, we will be releasing an extended series of blog posts over the autumn. These will consist of RDLS-inspired or extinction-related stories and projects from a broad range of contributing writers and artists. The image in this week’s post is a Micro CT scan of a sectioned thylacine skull from the D’Arcy Thompson Zoology Museum at the University of Dundee, downloadable in 3D here. Many thanks to Caroline Erolin of the Centre for Anatomy and Human Identification for sharing it with us.
The RDLS 2016 blog begins with this brief introduction to the idea of extinction from historian of race, science and empire, Dr Sadiah Qureshi of University of Birmingham:
Over ninety percent of all the beings that have ever lived on Earth are extinct. If you’re reading this, you’re lucky enough to be in the 10% that have survived. Between fifty and ninety percent of those lost to us have disappeared in five mass extinctions such as the one that eliminated the dinosaurs. We are now living through the sixth mass extinction. The disappearance of flora and fauna is familiar to us all. Yet how did we come to view such loss as extinction?
Before the nineteenth century, animals and plants were known to have vanished. Infamously, hungry sailors arriving on the island of Mauritius found that flightless dodos were easy to catch and made a hearty meal. The sailors also brought pigs, dogs, cats and rats that preyed upon the birds’ eggs and destroyed their habitat. No one knows exactly when the last dodo died, but most sources suggest that it was extinct by 1680. Crucially, humans were known to have caused the extinction.
Accepting that extinction was an endemic feature of the natural world posed problems for scientists and theologians throughout the eighteenth and early nineteenth centuries. For the faithful, the possibility of extinction undermined the perfection they expected of a world designed by God to reveal natural plenitude. In such a world, Creation always exhibited its fullest range of diversity and all possible forms of being existed.
For the faithless, it seemed far more likely that migration or evolution accounted for apparent loss. After all, much of the earth remained unexplored. Animals known only from fossils might be alive in tropical jungles or many leagues under the sea. The American President Thomas Jefferson, a keen collector of fossils, famously claimed that megabeasts might still be found in the far West. It was rare for anyone to claim that past forms might have evolved but it remained a possibility. By the early nineteenth century, evolution, migration and extinction were all seen as equally plausible theories for explaining natural loss.
Extinction became an increasingly popular theory with the work of French comparative anatomist George Cuvier. After the French Revolution, the government established the Musée d’Histoire Naturelle in Paris where Cuvier was given a job. He quickly gained a reputation for being a world authority on fossils and reconstructing entire animals from tiny handful of bones. In 1796 Cuvier published an article comparing a fossil elephant to living Asian and African elephants. He proclaimed that the fossil was an unknown and extinct species. Several more articles on elephants and the mastodon had appeared by 1806. Cuvier’s detailed anatomical research was compelling, and helped establish the reality of endemic extinction.
We are so familiar with extinction that it is easy to overlook the significance of the early nineteenth century. Accepting that extinction had always occurred in the natural world underpinned later theories of evolution, including humans, and conservation efforts. For Remembrance Day for Lost Species, it is also worth remembering the history of extinction of as an idea.