Marine Isotope Stage 9 (MIS 9) is a

Marine Isotope Stage Marine isotope stages (MIS), marine oxygen-isotope stages, or oxygen isotope stages (OIS), are alternating warm and cool periods in the Earth's paleoclimate, deduced from oxygen isotope data reflecting changes in temperature derived from data f ...

in the geological record. It is the final period of the

Lower Paleolithic The Lower Paleolithic (or Lower Palaeolithic) is the earliest subdivision of the Paleolithic or Old Stone Age. It spans the time from around 3 million years ago when the first evidence for stone tool production and use by hominins appears i ...

, and lasts from 337,000 to 300,000 years ago according to Lisiecki and Raymo's LR04 Benthic Stack, which has been adopted by the Subcommission on Quaternary Stratigraphy of the

International Commission on Stratigraphy The International Commission on Stratigraphy (ICS), sometimes referred to unofficially as the "International Stratigraphic Commission", is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigr ...

. It was an

interglacial An interglacial period (or alternatively interglacial, interglaciation) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene i ...

(warm period) which corresponds to the Purfleet Interglacial in Britain, and falls within the

Pre-Illinoian The Pre-Illinoian Stage is used by Quaternary geologists for the early and middle Pleistocene glacial and interglacial periods of geologic time in North America from ~2.5–0.2 Ma (million years ago). North America As the oldest stage in th ...

in North America. Some authorities regard it as corresponding to the Holstein Interglacial in continental Europe. Europe was then occupied by ''

Homo heidelbergensis ''Homo heidelbergensis'' (also ''H. sapiens heidelbergensis''), sometimes called Heidelbergs, is an extinct species or subspecies of archaic human which existed during the Middle Pleistocene. It was subsumed as a subspecies of '' H. erectus'' i ...

'', but they had probably retreated from Britain during the preceding glacial period. Populations returned as the climate warmed and sea levels rose around 330,000 years ago, and thousands of

hand axe A hand axe (or handaxe or Acheulean hand axe) is a prehistoric stone tool with two faces that is the longest-used tool in human history, yet there is no academic consensus on what they were used for. It is made from stone, usually flint or ...

s and other artefacts have been found along the terraces of the

Thames The River Thames ( ), known alternatively in parts as the River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the second-longest in the United Kingdom, after the R ...

and former

Solent The Solent ( ) is a strait between the Isle of Wight and Great Britain. It is about long and varies in width between , although the Hurst Spit which projects into the Solent narrows the sea crossing between Hurst Castle and Colwell Bay t ...

rivers. In Southern England, the summers were similar to or slightly warmer than today, and the winters slightly cooler. The period saw a transition from

Clactonian The Clactonian is the name given by archaeologists to an industry of European flint tool manufacture that dates to the early part of the interglacial period known as the Hoxnian, the Mindel-Riss or the Holstein stages (c. 400,000 years ago). Clac ...

culture for manufacture of stone tools.

References

{{reflist Marine isotope stages Interglacials