We provide a critical review of the evidence for the long-term use of marine resources and coastal environments in human evolution and later development. We emphasise the importance of the coastal archaeological record in understanding patterns of human settlement and dispersal and draw attention to the large potential biases introduced by the destructive or obscuring effects of Pleistocene sea-level change. We note that lowered sea levels have been the norm for most of the Pleistocene and that periods of high sea level have been too short-lived to provide other than a fragmentary coastal record and one that is beset with ambiguities and uncertainties. We examine the geological processes of coastal uplift and underwater preservation that may help to mitigate these biases. Coastlines elevated by isostatic and tectonic processes, or with very steep offshore drop-offs at plate boundaries, are important in providing a potential window into coastal landscapes and archaeology formed during periods of lowered sea level. However, we conclude that the opportunities afforded by these geological factors are too limited to obviate the need for underwater exploration. We review the evidence now available from submerged landscapes across the Africa-Eurasia interface from the Atlantic coastlines of Northwest Europe to the southern Red Sea. We show that geomorphological conditions for the preservation of archaeological and palaeoenvironmental data are commonly present, that much material has already been discovered, and that new techniques, technologies and projects are providing the momentum for a rapidly expanding field of investigation. The results do not simply add to what we already know from sites on land, but are likely to produce qualitatively different evidence for coastal adaptations and landscapes that have no analogue on present-day coastlines. We note the strong probability that many coastal landscapes exposed at lowered sea level provided relatively fertile and productive refugia for plants, land mammals and humans at a time when increased aridity would have reduced or deterred hinterland occupation. We conclude that underwater investigation is essential if hypotheses of early human adaptation and dispersal are to be fully tested.

The African and Eurasian plates are converging at 2.6 cm/a and the Turkey plate is moving west at about 3.0 cm/a. The Aegean is thus a zone of two-dimensional convergence. The boundaries of plates and sub-plates in this area cannot be defined at all simply. Observations of relative changes of sea level were made at 202 ancient harbour sites, some dating back to 2000 b.c., in Greece, Turkey, and Cyprus, and 175 independent estimates of sea level change were made. Measurements of uplifted and submerged recent marine solution notches in Antikythera, Crete, Karpathos, Rhodes, and Cyprus, showed that the islands of the Hellenic Arc are subject to intermittent seismic movements with a periodicity ranging from 157 to 714 a. The archaeological data and the notch data are combined to show that blocks with typical horizontal dimensions of 100 x 50 km at sea level are tilting intermittently as rigid units. The rates of tilt vary from 3.6 to 10.6"/ka. Stable blocks were identified in south Turkey east of Antalya, north Cyprus, and southwest Turkey from Kusadasi to Marmaris. The active areas are: the Peloponnese, where the peninsulae of Argolis and Messenia are subsiding; the central Peloponnese is probably doming or folding, while a slightly uplifted ridge extends east of south through Kythera and Antikythera; a graben structure separates Antikythera from Crete; west Crete is tilting northeast at a rate of 10.6" /ka; eastern Crete is tilting northwards at 10.3" /ka; Karpathos has subsided about 1.0 m maintaining horizontality; Rhodes is folding about a plunging anticlinal axis trending approximately east-west; in Turkey the Izmir-Cesme peninsula is subsiding, as is the coast from Fethiye to Cape Gelidonya; the south coast of Cyprus is subsiding irregularly. These data are used to construct a model of the subduction zone beneath the Hellenic Arc. It is concluded that there is no single planar or slightly curved subducted slab, since the zone bends through 90° south of Crete and again near the Anaximander Mountains. The quasi-linear sections of the subduction zone are interrupted by short tear faults and abrupt changes of strike at intervals of 50-100 km along their length. The resulting narrow fingers of slab tend to break, and are not subducted to great depth. Combination of this model with geophysical data allows construction of a new system of probable plate boundaries. It is suggested that there is no Aegean plate. The north Aegean is an extension of the Turkish plate, while the south Aegean is a region of crustal extension produced by gradual break-up of the southern margin of the Greek-Apulian plate. It is concluded that the Hellenic Arc is not an island arc in the normal sense, but represents a late phase in the destruction of a true island arc and back-arc sea by incipient continent—continent collision.

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We examine some long-standing assumptions about the early use of coastlines and marine resources and their contribution to the pattern of early human dispersal, and focus on the southern Red Sea basin and the proposed southern corridor of movement between Africa and Arabia across the Bab al-Mandab straits. We reconstruct relative sea levels in light of isostatic and tectonic effects, and evaluate their paleogeographical impact on the distribution of resources and human movement. We conclude that the crossing of the Bab al-Mandab posed little significant or long-lasting physical or climatic barrier to human transit during the Pleistocene and that the emerged continental shelf during periods of low sea level enhanced the possibilities for human settlement and dispersal around the coastlines of the Arabian Peninsula. We emphasise the paleogeographical and paleoenvironmental significance of Pleistocene sealevel change and its relationship with changes in paleoclimate, and identify the exploration of the submerged continental shelf as a high priority for future research. We conclude with a brief description of our strategy for underwater work in the Farasan Islands and our preliminary results.