About 9,000 years ago, the site of Atlit Yam was home to a vibrant village, where several houses, as well as a ritual place stood. A few centuries later, the area was submerged by the sea and today is located about 500 meters off the coast of northern Israel. Among the remains of buildings as well as of animals, plants and even several individuals, marine archaeologists identified a number of circular installations made of heated mud bricks. As a group of Israeli scholars from the Department of Maritime Civilizations and the Zinman Institute of Archaeology at the University of Haifa and the Israel Antiquities Authority found out, those ancient artifacts offer a key to understand how prehistoric populations in Israel evolved in ancient times, becoming more and more skillful and proficient in using the environment surrounding them. “In the Neolithic period, we start seeing the first sedentary settlements and the appearance of bricks is deeply connected to this phenomenon,” Isaac Ogloblin Ramírez, a PhD student and the lead author of the paper recently published in the Journal of Archaeological Science: Reports, told The Jerusalem Post.If at the beginning of the Neolithic era, bricks were simply dried out in the sun, as ancient populations developed pyro-technologies, the artifacts started to be fired, which increased their resistance to the point of allowing them to survive for millennia under the sea.For the study, the researchers considered bricks found in sites from different periods, both submerged and not. Underwater survey and collection of samples for analysis was conducted with the assistance of the Recanati Institute for Maritime Studies at the University of Haifa.Atlit Yam and Bnei Brak – located in the Sharon Plain – date back to the pre-pottery Neolithic C, when pottery was not yet manufactured. Neve Yam and Ein Asawir – the first located not far from Atlit but just a few meters from the shore and the second also in the Sharon Plain – are from the more recent period of the Neolithic Wadi Rabah phase.The oldest bricks were manufactured in some form of an oval shape up to 40cm. long and 38cm. wide, while the most recent were in a semi-rectangular shape and slightly smaller – with the largest found approximately 30x50x10cm. in size.“This is the first time we have discovered evidence that mud bricks in the pre-pottery Neolithic sites were heated,” Ogloblin explained. “We found the bricks in circular concentrations, which we believe were related to some form of use of fire, like an oven. However, we don’t know if those concentrations were simply the areas where the bricks were manufactured, or their final purpose. Atlit Yam is the only site where we found evidence that heated mud bricks may have been used to build a wall.”In the different periods, the composition of the bricks changed, showing a crucial evolution in the skills of their creators.“Pre-pottery Neolithic mud bricks were very simply made of clay, quartz and a little calcite,” the researcher pointed out. “In the Neolithic Wadi Rabah phase, the level of knowledge and craft improved: together with clay, quartz and a lot of calcite, which was associated with pottery making, the manufactures were adding many different elements like domesticated wheat straw, fragments of bones and flint.”Ogloblin highlighted that this is especially meaningful because it showed how those ancient people were good at reusing materials but also because these additions made the bricks lighter and facilitated the heating process, requiring lower temperatures to fire them.“This increase in skills has social implications too: it tells us how those populations were starting a more intense use of the environment surrounding them. We believe that the manufacturing of mud bricks marked the beginning of the period that we call the ‘secondary product revolution’,” he said.The presence of wheat is also important because it gives insights into the process of plant domestication.“In the development of heated mud bricks through time, we see how prehistoric humans learned how to interact with the materials and the environment,” he concluded.