Age· The columns of time

Calabrian

1.8 Ma → 774 ka

The Calabrian, from 1.8 million to 774,000 years ago, is defined by a golden spike that once marked the base of the Quaternary and was reassigned in 2011 after that base was lowered.

Age defined by a golden spike previously assigned to the base of the Quaternary, and reassigned in 2011 after that base was lowered.

What the evidence shows

The Vrica section, in Calabria, defined the base of the Quaternary from 1985, at 1.80 million years. When that base was lowered to 2.58 million years in 2009, the section was reassigned in 2011 to define the Calabrian: the same physical marker, without being moved, changed function. During this age the glacial cycles follow the short 41,000-year rhythm, and hominins spread across Africa and Eurasia. Burnt bone and plant ash from Wonderwerk cave, in South Africa, dated to about a million years, constitute the oldest secure evidence of fire in a place occupied by hominins. Towards the end of the age the glacial rhythm begins to change, from short cycles to the longer and deeper ones that will govern the rest of the Quaternary.

Bounds and conventions

The limit is firm, having been established before being assigned to the Calabrian. The change in glacial pacing beginning in this age has no accepted cause and is known as the Mid-Pleistocene problem. The Wonderwerk trace attests a fire in a cave, which does not establish that its occupants could produce one.

Vrica GSSP, reassigned in 2011.