Pinnacle Point

Listen first. Below you, the Indian Ocean breaks against dark rock. The spray drifts up the cliff face, and the air tastes of salt. Underfoot, the ground is hard sandstone, scattered with low, tough shrubs. You are standing on a stretch of coast that looks wild and quiet. Yet scientists now count this cliff among the most important places on Earth for understanding where modern humans came from.

Pinnacle Point sits just west of the town of Mossel Bay, on South Africa's southern coast. The cliffs here are made of quartzite and sandstone, very old rock that the sea has worked on for an enormous length of time. Waves and weather have cut a series of caves into the cliff face. Archaeologists gave them numbers rather than names. One of them, known as Cave 13B, changed the way researchers think about our species.

The work here began in earnest in the early 2000s. An international team, led by the archaeologist Curtis Marean of Arizona State University, started to excavate the caves layer by layer. They moved slowly. They measured, sieved and recorded almost every grain. Above the cliffs, the land was later developed into a golf estate. So the quiet greens you may have passed on the way in sit almost on top of one of the oldest records of human behaviour anywhere.

Here is the first surprise. In 2007, the team published results in the journal Nature. They reported that people were living in Cave 13B around 164,000 years ago. And those people were doing something new. They were eating shellfish — mussels, limpets and other creatures gathered from the rocks below. At the time, this was the earliest clear evidence of humans living on food from the sea.

Why does that matter? Shellfish are a reliable food. They do not run away, and they are rich in protein and healthy fats. To collect them safely, people had to understand the tides, and probably the phases of the moon that control those tides. That kind of planning points to a mind much like ours. The same layers also held small, carefully shaped stone blades, and pieces of red ochre that people had scraped and ground.

Red ochre is an iron-rich earth pigment. It can be used for practical tasks, such as making glue or treating hides. But many researchers also link it to colour, decoration and symbols — the early roots of art and identity. Finding it here, so long ago, suggested that people on this coast already lived with ideas, not only with survival. Standing on this cliff, it is worth pausing on that thought for a moment.

To picture their world, you need to move the coastline. During cold periods of the Ice Age, a great deal of the planet's water was locked up in ice. Sea levels fell, and the shore sat much further out than it does today. At times, the people in these caves would have walked across a wide coastal plain to reach the water. Today, the ocean comes almost to the foot of the cliff.

That cold period is the key to the main idea behind the research. Professor Marean and his colleagues have argued that this southern coast may have been a refuge. When much of Africa became cold and dry, this narrow strip still offered food. There was shellfish from the sea. There were also edible bulbs and roots in the plants of the land. A small human population, the argument goes, may have survived here through hard times.

Those plants are still around you. The shrubby vegetation on these cliffs is fynbos — spelled F-Y-N-B-O-S — a type of fine-leaved bushland found almost only in this corner of South Africa. It belongs to the Cape Floral Region, one of the richest plant areas in the world. Many fynbos plants store energy in underground bulbs and tubers. For early people, those bulbs were a hidden pantry under the soil.

The second surprise comes from fire. Researchers working at Pinnacle Point found that people here heated a local stone called silcrete before shaping it. Gentle heating makes the stone easier to flake into sharp, precise edges. This is not a simple trick. It needs control of fire, patience and a clear sequence of steps. Later layers in another nearby site also showed very small, finely made blades, the kind that could be set into handles or shafts.

There is one more remarkable find. In a site the team calls Pinnacle Point 5-6, researchers reported tiny shards of volcanic glass. They linked these shards to the huge Toba eruption in Sumatra, in Indonesia, about 74,000 years ago. Some scientists once believed that eruption brought humanity close to extinction. But the evidence here suggests that people on this coast carried on living, and even did well, through the years that followed.

The caves are protected, and you cannot simply wander into them. The excavated sites are fragile, and access is usually by guided tour arranged in Mossel Bay. The walk down involves steps and steep sections on the cliff. Guides normally bring the story to life at the cave mouths and along the path. Mossel Bay itself has a long human story as well. The Portuguese explorer Bartolomeu Dias landed here in 1488, one of the first Europeans to reach this shore.

Before you leave, look out once more across the water. Watch the waves wash over the dark rocks at the cliff's base — the same kind of rocks where people once gathered mussels. Notice the wind in the fynbos, and the shape of the cave openings in the cliff. Thousands of generations passed between those first shellfish meals and your visit today. As you walk back up toward the town, the coast will look much the same. But you will know what it once held.