About the Quaternary
The Quaternary is the name given to the last 2.6 million years of geological time. This period is of extreme importance to humans since it is during this period that man rose from being simply another member of the vertebrate fauna to the present pre-eminence. It is also a period that has included major climatic changes that among other things caused vast ice sheets to grow and advance into what are now temperate regions on all continents. Mountain chains all over the world also supported ice caps. These ice ages recurred several times, the most recent being only 12,000 years ago. The build up of ice on the land led to lowered sea level as the water became stored as ice. Sea levels have therefore also fluctuated many times in the last 2 million years. Between these ice ages were periods of warmer climate like that in which we are now living, called interglacials. These are characterised by conditions like those now, i.e. relatively high sea level and warm climates in temperate areas like Britain.
The climatic shifts have not only had physical effects, but have caused vast shifts in plant and animal populations, such that in interglacials forests have grown in temperate areas, whilst during cold or glacial periods trees have been prevented from growing and instead tundra-like grassland or under the most severe conditions, arctic desert has occurred in NW Europe.
These climatic changes are often rapid and profound. For example the change from the end of the last ice age into our present interglacial (we are still living in the Quaternary) took less than 100 years. It appears that the changes are brought about by changes in the Earth's orbit around the Sun. This has been demonstrated by the immense volume of research that has been done on deep sea sediment cores. These cores provide long continuous sequences of sediment, the fossils in which provide a record of climatic and ocean environmental change for the whole period. This record contrasts to that on land areas like Britain because here local erosion by glaciers, rivers, the sea and the wind cause discontinuous sequences to be preserved. The terrestrial record of climate change is therefore fragmentary. However, against this must be set the fact that the terrestrial record offers immeasurably greater detail, much of it of more local importance, than can be achieved from cores from the oceans.
For humans the Quaternary is of prime importance therefore because it provides us with a foundation upon which to build our understanding of the impact of our activities on our World and the way in which we might expect it to respond in the very near future. Clearly any response may be small, but lessons from the past suggest that sufficient minor change can have profound effects in a few short years, witness for example the possible changes predicted for the so-called Greenhouse effect' etc. These changes may take various forms from minor changes of daily weather to large -scale climate change, sea-level rise, melting ice-caps etc. At a more local level, changes may have enormous consequences for landowners whose property is submerged or crops are lost as a result of severe weather.
In essence therefore we cannot afford not to study the Quaternary Period if we are to understand the long term and even the shorter term operation of the planet upon which we live.
More on the term Quaternary .