Quaternary science

It aims to understand the Earth's environment during these recent epochs, including ecosystem, climate changes, geography, biology, chemistry, and physics. It helps provide a framework to interpret archaeological records.

History

The Quaternary Period is conventionally divided into two epochs: the Pleistocene lit. 'most recent', beginning about 2.58 million years ago, and the Holocene lit. 'wholly modern', which began about 11,700 years ago.

The term Quaternary was first used by Italian engineer Giovanni Arduino in the late eighteenth century to describe the four most recent geologic eras. It is subsequently regarded as "a phase of highly variable climates, with marked periods of time when global temperatures were significantly lower than today and evidence for which was interpreted by Louis Agassiz as indications of a geologically recent 'Great Ice Age'".

In the early nineteenth century French scientist Georges Cuvier proposed that some animals that lived in the Pleistocene epoch were made extinct by some environmental 'revolution' (e.g. some catastrophic flooding events).

Later in the nineteenth century the cause and influence of ice ages also developed. Scottish scientist James Croll recognised the significance of positive feedbacks in the climate system, including of ice-albedo. His theory was also the first to predict the cause of glaciation.

In the twentieth century Milutin Milankovitch, a Serbian mathematician and geophysicist, developed a theory linking long-term climate changes to the motion of the Earth. It offered information about the changes in seasonal "insolation" (incident solar radiation) over millions of years. André Berger, a Belgian climatologist, identified certain time periods where reconstructed insolation deviated significantly from the average. Many of his analyses show that from May to August, there has been a forwarded shift of insolation maximum (higher than average) during the late Quaternary. This feature is known as "insolation signature" and may relate to changes in climate as contemplated by Berger.

Subsequent work in palaeoecology, palaeontology and palaeoclimatology has revealed relationships between changes in the environment and the planet's history during the Quaternary.

Quaternary science has also yielded insight into human colonization and mobility, providing data about the environment and landscape affecting human evolution.