What’s on : Lectures

Mapping the Anthropocene impact on the biosphere

Lectures
Date
15 Oct 2019
Start time
7:30 PM
Venue
Tempest Anderson Hall
Speaker
Professor Mark Williams, University of Leicester

Event Information

Mapping the Anthropocene impact on the biosphere

‘How people have totally changed the pattern of life on Earth’

Professor Mark Williams
School of Geography, Geology and the Environment, University of Leicester.

Most species on planet Earth have ecological ranges defined by factors such as latitudinal changes in surface temperature and rainfall, or geographical isolation. These patterns have evolved over millions, sometimes tens of millions of years. This natural pattern is being overprinted by the actions of Homo sapiens, which has made the whole Earth its ecological range. The human ancestral pattern of gradually increasing influence on the Earth can be traced in the stratigraphic record for nearly 3 million years, as a time transgressive pattern beginning in Africa, and gradually extending throughout the world by the late Pleistocene. However, in its later and more pervasive stages, particularly from the mid to late 20th century onwards, it provides intercontinental patterns of species distributions with clearly identifiable biostratigraphical signatures that may help to define an isochronous stratigraphical boundary for the Anthropocene. Moreover, these biostratigraphical patterns map a profoundly human-changed biosphere.

Nuffield Partnership Award students will present their research on posters in the Atrium of the Museum at 6.15pm – further details to follow.

Poster image of Alexander Von Humboldt and Aimé Boupland in South America formulating key ideas about the biosphere.

Member’s report

Earth’s history can be traced in the geological record from its beginnings. The present Cenozoic Era (meaning new life) began 65.5 million years ago (mya) after the mass extinction caused by an asteroid impact. Predation by humans since their first appearance 2.8mya has caused an ongoing extinction of fellow creatures. The most recent epoch, the Holocene, also called the Anthropocene, began at the end of the Ice Age, some 11,700 years ago. Since then, humans have caused a mass extinction of megafauna. We outnumber every other hominid species (97% of the total) and continue to deplete Earth’s resources and its biodiversity.

Humans have also modified 95% of ice-free land, the results of which will remain for ever. The Anthropocene rock record will contain evidence of roads and buildings – and reflect the change from regional materials to globally traded concrete and steel; technofossils will show our habit of boring through rocks to enable mass-transportation in tunnels under our megacities. Tools will be most evident (from flints, to bronze, iron, and plastic), and the effects of agriculture on wild plant and animal life. It will show our cities sinking because of water extraction; and it will show our use of radioisotopes since the 1950s.

Is this parasitic relationship with Earth sustainable? Only if we alter our behaviour.

Carole Smith