Australasian Science: Australia's authority on science since 1938

Explorer’s Tragic Burden Transformed Geology

By John Long

Scott’s tragic Antarctic expedition sowed the first seeds of Gondwana.

Sir Robert Falcon Scott’s ill-fated expedition to Antarctica in 1912 is mostly remembered for its tragic end where Scott, Oates, Bowers and Wilson all perished trying to make it back to their base camp. Some historians criticised Scott for his lack of careful planning, but other theories attribute their demise to an unlikely extreme cold weather event that struck the party’s last march to find their depot.

What few people realise is that as the men weakened from lack of food and the hard work of pulling sledges along, they still carried some 16 kg of rock samples. These were collected on the long march back from the South Pole, near the Beardsmore Glacier. The day was recalled in Scott’s diary with great fondness as a very happy day, a much-needed break from man-hauling the sledges and instead spent “geologising”.

Their return trek became more arduous as food supplies diminished, so they discarded most of their unnecessary gear. But at Edward Wilson’s request they carried the precious rocks with them. When Scott, Bowers and Wilson were found dead in their tents, the rocks were duly collected and eventually made their way back to the British Museum of Natural History.

In 1914 British palaeontologist Albert Seward published a description of fossil plants found in the these rocks. He made the amazing discovery of fossil leaves identified as Glossopteris and Vertebraria, both well-known from countries not close to Antarctica such as India. Today we know the Vertebraria are just the roots of the Glossopteris tree, an ancient kind of now extinct tree called a “seed fern”. These species at the time were also known from Australia, Africa and South America, but absent from large Northern Hemisphere countries such as Europe and North America.

The term “Gondwana” was first used by Irish geologist Samuel Medlicott, who lived and worked in India during 1854–87, in a local sense to describe Permian formations in the region. It means in Sanskrit “forest of the Gonds” (a local tribe). These strata contained the fossils of Glossopteris.

In 1885 Austrian scientist Eduard Suess studied the fossils of Glossopteris and noted their strange distribution. He discovered that sea level could rise and fall with geological time, and at first thought (in 1885) that land bridges had connected Australia, Africa, India and South America, where the Glossopteris trees once lived. His concept of the “Gondwanaland supercontinent” was not as we envisage it today – a result of drifting of continents uniting. He thought that ocean levels had dropped to connect the continents, and today the rise of seas flooded the spaces currently between those lands.

It was Scott’s rocks that added a new piece of data to the developing theory, as now the Glossopteris trees were also in Antarctica. By co-joining the places where Glossopteris now occurred, Antarctica becomes the lynch-pin of the super­c­ontinent.

It would be many decades after Alfred Wegener proposed his concept of “continental drift” (1912) that an American geolophysicist, Jack Oliver, would find proof for the mechanism explaining how continents can actually move. Today Antarctica remains an intensely significant place for geological and palaeontological studies simply because it is the very hub of Gondwana.

Next month I will head on my third fossil-hunting expedition to Antarctica to search for Devonian-age fossil fishes in the central Transantarctic Mountains. I shall write next month’s column about why we are going there and what significance Antarctica holds for solving modern problems in palaeontology. Stay tuned.

John Long is Strategic Professor in Palaeontology at Flinders University, and current President of the Society of Vertebrate Paleontology.