# Coastal and island submergence during the Epipaleolithic in the Sicilian-Tunisian Strait: consequences for early navigation between the two shores of the Mediterranean

Christian Depraetere¹

¹ Institut de Recherche pour le Développement, UMR Espace-DEV, Maison de la Télédétection, 34000 Montpellier, France

christian.depraetere@ird.fr

## Abstract

Paleontologists and archaeologists are still debating about whether or not there was frequent sea crossing of the Sicilian-Tunisian Strait (STS) during Epipaleolithic and Early Neolithic, but it is proved for instance by the dispersal of obsidian from the quarrying sites of Pantelleria. One aspect of the controversy concerning cabotage over coastal waters without effective seafaring across open sea revolves around navigation capabilities of prehistoric populations with dug-out canoes of only a few meters or rafts, probably without sails. Avoiding getting into this intricate debate of specialists, one argument explaining the limited number of archaeological findings prior to the Neolithic rests on the fact that the population density was much lower except along the coastal zones. Furthermore, most archaeological sites of these small communities of nomadic or semi nomadic hunter-fisher-gatherers (HFG) must be now under water! Nevertheless, it is worth noting that “routine navigation across open seas in pre-Neolithic times, possibly as early as 12 000 BP” is a widely accepted hypothesis, at least in Aegean Sea.

The present study focuses on the environmental context of the period between 16 500 and 7 000 BP, characterized by a high rate of sea level rise (SLR) of 1 to 2 meters/century and subsequent fast marine transgression with coastal plain submersion and shrinkage of paleo-islands. This phenomenon of coastline retreat and “island shrinkage” lasting several millennia is well-documented in the paleogeographic context of the Sicilian-Tunisian Strait and along the southern Tunisian coastal zone. In the central part of the Mediterranean, proofs of obsidian quarrying and trading have been found in several islands including Pantelleria, Lipari, Palmarola and Monte Arci in Sardinia.

The pace of land and island shrinkage processes is detailed at five locations: the paleo-plain of Adventure bank in southern Sicily, the Siculo-Maltese Paleopeninsula, the Paleo-island of La Galite in Tunisia and the large Paleoplain of the Tunisian Plateau and mostly the Paleo-island of Pantelleria.

Continuously during this period of 10 thousand years, one generation after the next had to deal with the ever-changing conditions of near shore navigation as well as crossing ever larger channels. The entwined evolution of environmental conditions and human communities is so tight that it has to be taken as a regional showcase of the “geohistorical” process.

**Keywords:** Paleogeography, Sea level rise, island shrinkage, Epipaleolithic, Archaeology, Tunisia, Sicily, Obsidian, seafaring.
# 1 Introduction

It is worth to mention the ongoing debate about navigation skills of Paleolithic and Neolithic population because archaeological findings remain limited up to now. Nevertheless, several recent discovery proves that communities at those times were able to settle down on remote islands in different part of the world. It is the case for *Homo erectus floresiensis* and *luzonensis* in Wallacia (between the Sunda Shelf and the former continent of Sahul, about 100,000 BP), Aborigines in Australia (via Wallacia, 65,000 BP), Paleolithic *Homo sapiens* probably on many Mediterranean islands for instance Cyprus, Crete and Sicily including Malta which remains part of a Sicilian peninsula till 14,000 BP. This new challenge for paleontologists boosts underwater archaeology to find out traces of human occupation including submerges caves when the Sea level (SL) was much lower [1] [2].

# 2 The paleo geohistorical context of the Sicilian-Tunisian Strait.

The Sicilian-Tunisian Strait (STS) presents some analogies with other regions of the world where islands are paving the way between two continents: Wallacia between Southeast Asia and New Guinea, the Caribbean between Venezuela and Florida, the north Atlantic islands between Europe and North America. Likewise Wallacia and to a certain extent to Caribbean, marine navigations and migrations via the STS can be done as an “island hopping” process, islands being within sight to each other’s. This is not the case for the north Atlantic islands and furthermore for the Pacific island which relates to a far more challenging process of "island hoping" [3] [4].

As shown on Map 1, the land patterns and the seashores where drastically different 20,000 BP. Conversely, the geographical settings of around Cyprus and Crete were not as much unlike as there are now. The main different features are the paleo Siculo-Maltese and Adventure Bank peninsulas, the paleo plain of Tunisia, the paleo island of La Galite. In the case of Pantelleria, the “island shrinkage” phenomena due to Sea level rise (SLR) since then did not change much the size of the island (138 km² compared to 83 km² today). The shrinkage was more important in the case of La Galite (185 km² now 10 km²) or for the island of Gavdos at the southeast of Crete (250 km² now 35 km²). In the STS 20,000 years ago, there was several islands entirely submerged now as the Pine Marine and the Sherki banks. These cases of total submersion are emblematical illustrated by the Dogger Bank, so called “Doggerland”, in the North Sea where archaeological findings prove that this former island was inhabited during the Paleolithic [5].
<figure><img src="image_1.png" /><figcaption>**Map 1. Paleogeography of the Siculo-Tunisian strait 20,000BP**
(bathymetry from EMODNET DTM 2022)</figcaption></figure>

This map shows that the channel between the paleo coastlines of Sicily and Tunisia was narrower than it is now with many islands and islets as stepping-stones between the two mainlands (50 km instead of 145 km). For archaeologists, the island of Pantelleria right at the middle of the channel deserve attention because it was one of the main source of obsidian for the entire region. Thus, this means routine or at least regular shipping from the island to mainlands [6].

# 3 Results

## 3.1 Means of navigation and the nautical skills

We have to take into account the means of navigation and the nautical skills of the Paleolithic communities as they are assumed to be by paleontologists and archeologists now.

They suppose that boats were limited then to dugout canoes carved from tree trunk (monoxylon) and rafts without sail that can only be moved with paddles by hunter-fisher-gatherers (HFG) communities familiarized with near shore navigation for many generations. With good conditions at sea (moderate current, gentle breeze and light swell) and guessing an average speed of 2 km/hour, this means that the boat trip between the two mainlands was of the order 25 hours of paddling. From Pantelleria Shoal to Pantelleria where there was obsidian quarries the distance was 16 km, about 8 hours of navigation.
## 3.2 The pace of SLR, coastline retreat and “island shrinkage”

The Palaeolithic and Early Neolithic communities were confronted to a fast SLR noticeably between 20,000 and 7000 BP (Figure 1): several pulses before 11,000 BP then a steady rise of 1.9 meters/century up to 8000 BP.

<figure><img src="image_2.png" /><figcaption>Figure 1. Mediterranean's SLR 20,000 to 4000 BP (adapted from [7] [8]).</figcaption></figure>

During 10,000 years, many generations of HFG seafarers and early farming populations experienced a continuous submersion of their coastal plains and fast evolution of navigation conditions. The phenomenon was even worse for island communities faced up to the steady shrinkage of their land with the fear that it could disappear entirely; this may had happen for La Galite, Malta and Kerkennah (Map 2). In these cases, a “Doggerland syndrom” could occur within islander communities having in mind the dreadful ultimate option of the island abandonment [9]: the boat or the death!

<figure><img src="image_3.png" /><figcaption>Map 2. SLR and coastal retreat in the STS from 16,500 to 7000 BP (paleoshores from EMODNET DTM 2022)</figcaption></figure>

The retreat of coastline was not so scaring for HFG living on the seashores of mainlands or big islands. Generation after generation, they had to move back to the large hinterland which could create tensions with local tribes. The speediness of the coastal submersion process depends of the plain slope gradient. Assuming a SLR of 2 meters/century (cf. Figure 1) and a gradient of 1 percent, it means a transgression of 2 meters per year thus 200 meters per century. Such a
dramatic evolution should have occurred on Adventurer Bank (4400 km²), the isthmus between Sicily and Malta (5000 km²) but also at a larger scale on the Tunisian Plateau (61,000 km²). Up to the end of the Neolithic, the Kerkennah and Jerba islands were still part of peninsulas as shown on Map 2C.

### 3.3 The case of Pantelleria and its obsidian quarries

The distance from Pantelleria to the shores of Adventurer Bank and Tunisia was respectively of 17 km and 47 km whereas it is now of 100 km and 70 km. Considering all the emerged lands at that time, getting across the strait was easier for geographical reasons (Map 3). The optimal island hooping steps minimizing navigation was between Adventurer Bank and the paleo shores of near the Cap Bon via the paleo islets of Talbot, El Haouria and Zoemides banks (less than 20 km).

Pantelleria was almost the unique provider of Pantellerite obsidians from the Epipaleolithic and during the Neolithic in North Africa including findings in Kerkennah island [10]. In Sicily, obsidians could be coming also from Lipari or Sardinia at Monte Arci. Map 4 shows the location of the three main obsidian outcrops at the border of the two calderas [11] as well as the detailed topography and bathymetry of this island.

### 4 Discussion

This exploratory work advocates for more underwater archaeology to unfold the geohistory of the first Mediterranean seafarers. This challenging goal requires the intensive use of a set of ad hoc technologies to survey and locate submerged archaeologic sites.

As far as now, there are no archaeological proof of sail usage before 3500 BP but it does mean that there was no. From an anthropological perspective, few questions rise up about the possibility of a "Doggerland syndrom" especially on small flat islands. The key question remains why did the "mainland" communities decided to settle on islands even though they had some drawbacks ... but also advantages. Apart from specific mineral ore (i.e. obsidian on volcanic islands such as Pantelleria, Lipari or Milos), islands offer more fishing grounds, shelter large colonies of Mediterranean monk seals (no terrestrial predators), appropriate nesting area for sea turtles and even dwarf species of elephant and mammoth (Malta for instance). Last but not the least, their remoteness and isolation avoid direct contact with neighboring communities but conversely they are more prone to raids of "sea peoples" or pirates.

The Doggerland syndrome associated to island shrinkage processes may have contribute to legends and myths of submersion in the Mediterranean and other parts of the world. Today, this is happening in few countries in the Pacific or in Asia.
6

<figure><img src="image_4.png" /><figcaption>Map 3. Bathymetry of the STS around Pantelleria (isobaths from GEBCO 2023)</figcaption></figure>

<figure><img src="image_5.png" /><figcaption>Map 4. The island of Pantelleria and obsidian quarries
(bathymetry from EMODNET DTM 2022 and topography from GLO-30 DEM Copernicus)</figcaption></figure>
## Conclusions

Despite Mediterranean voyages at sea were quite adventurous during the Epi-paleolithic and Early Neolithic, many migrations and tradings took place in the SPS as suggested by recent archaeological works.

The paleogeographical configuration about 20,000 BP strongly suggests the possibility of frequent migrations and trading throughout the STS despite limited nautical capacities Epipaleolithic seafarers. Part of these migrations were related to steady marine transgression all along this period of ten thousand years which causes the submersion of more than 100,000 km² of favorable hunting grounds and farming lands in central Mediterranean.

## References

1. Campbell, P.: The Archaeology of Underwater Caves. Highfield Press, 250 pages (2018).

2. Antonioli, F. et al.: Human settlements in the Mediterranean and the sea level changes from 12 ka to the present. Rendiconti Online Societa Geologica Italiana. 18. 5-7. 10. (2012).

3. Depraetere C.: The Challenge of Nissology: A Global Outlook on the World Archipelago, Part I: Scene Setting the World Archipelago. Island Studies Journal, a scholarly journal dedicated to the inter-disciplinary study of our 'world of islands', Vol. 3, No. 1, 2008, pp. 3-17 (2008).

4. Depraetere C., Dahl A.L.: Island locations and classifications. In 1st Edition The Routledge International Handbook of Island Studies: A World of Islands. Routledge, May 2018, 500 pages, pp.21-51 (2018).

5. Hoebe, P.W. et al.: Early Holocene inundation of Doggerland and its impact on hunter-gatherers: An inundation model and dates-as-data approach. Quaternary International, Volume 694, 2024, Pages 26-50 (2024).

6. Freund, K.: A long-term perspective on the exploitation of Lipari obsidian in central Mediterranean prehistory. Vol. 468, 109-120, Quaternary International (2018).

7. Vacchi, M. et al.: Multiproxy assessment of Holocene relative sea-level changes in the western Mediterranean: Sea-level variability and improvements in the definition of the isostatic signal, Earth Sci. Rev., vol. 155, pp. 172-197, (2016).

8. Benjamin, J. et al.: Late Quaternary sea-level changes and early human societies in the central and eastern Mediterranean Basin: An interdisciplinary review, Quaternary International, vol. 449, 2017.

9. Dawson, H.: Mediterranean Voyages, the Archaeology of Island Colonisation and Abandonment. Left Coast Press, Institute of Archaeology Publications 62, University College London (UCI), 1st Edition, Pages 324 (2014).
10. Mulazzani, S. et al.: Obsidian from the Epipalaeolithic and Neolithic eastern Maghreb, A view from the Hergla context (Tunisia). Journal of Archaeological Science. 37. 2529-2537. (2010)

11. Rotolo, S. et al.: Obsidians of Pantelleria (Strait of Sicily), A Petrographic, Geochemical and Magnetic Study of Known and New Geological Sources. Open Archaeology. 6. 434-453. (2020)