THE prehistorian Alexander Marshack, who documented the earliest calendars and notation systems dating back some 30,000 years, came to archaeology late in life after a career in journalism and films. But he brought to his adopted discipline the flair for making the complex comprehensible that had stood him in good stead at Time-Life Inc. Born and brought up in New York and educated at the City College of New York, Marshack retained all his life the enthusiasm and charisma of the metropolitan communicator.

In his early forties he became interested in the human past, a topic on which Time-Life books had published a number of titles; he saw in the non-representational “signs” of Palaeolithic art, neglected by prehistorians such as the Abbé Breuil as they pursued animal paintings and hypotheses of sympathetic magic, evidence for the structured working of the early human mind. In particular, he believed that the repetitive series of short strokes or other simple signs made on bone fragments were neither accidental scratches nor hunting tallies, but reflections of much more complex intellectual processes.

From 1966 onwards, with support from the National Science Foundation, private foundations and the National Geographic Society, Marshack scrutinised every incised object from a Palaeolithic context that he could lay his hands on, spending months at a time immured in European museums and becoming one of the first scholars to be allowed to work extensively in Soviet collections. In this he was aided by appointment as honorary Research Fellow at the Peabody Museum of Harvard University, an act of faith by the late Hallam L. Movius.

Though Professor François Bordes in Bordeaux had published Marshack’s first book on the topic, Notation dans les gravures du Paléolithique Supérieur, in 1970, his work first made an impact on the profession and the public at large with The Roots of Civilization: the Cognitive Beginning of Man’s First Art, Symbol and Notation (1972). The book claimed that the mental processes of our ancestors some 30,000 years ago (at the time almost the earliest known date for Homo sapiens sapiens) were no different from our own. Put out through a trade publisher in a generous format, abundantly illustrated, and publicised by Marshack’s own expansive appearances, the book had an immediate effect on archaeological thought, although some of it was negative. It established Marshack as a protagonist in the constant arguments over the nature of our ancestry that have been one of the most productive areas of archaeological research in the past 40 years.

Marshack developed microscopic methods of analysis that could show the precise sequencing and internal structure of the apparently uniform sets of markings on Palaeolithic objects, even to the extent of demonstrating where the graver had been turned in the hand or replaced by another tool to maintain a sharp edge. He also pioneered the use of infra-red and ultra-violet techniques to study problems as diverse as the cave paintings of Lascaux and the palimpsest charcoal markings on a modern Maya calendar board.

In 1978 he was guest curator for the important Ice Age Art exhibition at the American Museum of Natural History that was largely responsible for introducing the subject to the American public.

His more recent work focused on the evolution of human cognition, and the neuropsychological content of early symbol systems. He concerned himself in the debate over the intellectual capacity of Neanderthal Man, and was honoured in Britain as the first McDonald Lecturer in the new archaeological institute of that name at Cambridge University in 1989. In his lecture he presented a masterly analysis of the Taï plaquette, which may be the most complex calendrical notation known from the Ice Age.

In the 1990s some younger scholars took exception to Marshack’s structuralist interpretations, preferring to see more magical and religious motives behind Palaeolithic phenomena and decrying Marshack’s approach as excessively numerological. Having avoided the backbiting endemic to an academic career, Marshack was personally much hurt by these attacks, some of which were, indeed, pressed ad hominem rather than in a spirit of intellectual scepticism. While some of the caveats seem valid, the extent to which Marshack reorientated attitudes to the intellectual processes and achievements of our distant ancestors should not be underestimated.

He continued, though, to work with enthusiasm and energy. In particular he was responsible for important studies of a Mousterian (ie, Neanderthal) engraving of nested arcs on a flint cortex from Quneitra in Israel; and of the immensely important “proto-figurine” from Berekhat Ram, also from Israel, which is probably more than 300,000 years old. Marshack was the first to prove that this tiny piece of stone had indeed been modified by Homo erectus.

His prodigious capacity for work lasted until a stroke in 2003, followed by a serious fall, destroyed his health.

He is survived by his wife, Elaine. An earlier marriage was annulled.

Alexander Marshack, Ice Age expert, was born on April 4, 1918. He died on December 20, 2004, aged 86.