Two details that changed the picture
Two details tend to be left out of the standard postcard image of Easter Island. The first is the red cylinder sitting on the head of some statues, called a pukao. The second is that the heads on the quarry slope are not only heads: excavation has shown that many belong to full torsos buried deep in the soil, some carved with designs that had been hidden for centuries. Both discoveries show that the moai were more elaborate than the weathered stone suggests.
What a pukao is
A pukao is a large, roughly cylindrical block of red volcanic stone that once sat on the head of a moai. Rapa Nui people use the word for a topknot, and many researchers think the shape represents a hairstyle in which the hair was gathered and tied on top of the head. The comparison with Polynesian traditions of hair-knots worn by high-ranking men is common, though it is an interpretation, not something stated by the statue-makers themselves.
Roughly a hundred pukao have been recorded, and only a minority of moai ever wore one. Many of those found today lie on the ground near the platforms where they once stood, since they fell or were pulled off when the statues were toppled. Some are about two metres across and weigh several tonnes. A few have a hollow on the underside, which fitted over a notch or shaped surface on the head, and some have a small projecting knob on the front.
The Puna Pau quarry
The pukao were cut at a separate site called Puna Pau, a small volcanic cone in the west-centre of the island. The stone is red scoria, a light and porous volcanic rock whose colour comes from oxidised iron. Its colour contrasts with the grey-brown tuff of the statues, and it was probably chosen for that reason as well as because it can be worked.
Like Rano Raraku, Puna Pau preserves the traces of its use. Unfinished and abandoned pukao lie around the quarry, which tells researchers that they were shaped at the source and then transported. They were then raised onto the heads of statues that stood on platforms, sometimes far from the quarry. How a multi-tonne block was lifted to the top of a statue several metres high is unresolved. Proposals include ramps of earth or rubble, rolling the stone up an incline, or levering it in stages. Experimental work has demonstrated that such methods are feasible, though that does not show what the islanders did.
Why red?
The red colour has generated ideas about symbolism. In many Polynesian contexts, red was associated with high status and sacredness, and Rapa Nui traditions use red pigment in other settings. These associations are plausible context, not proof. What can be said safely is that the pukao were deliberately made from a distinct stone that was brought from a distinct place, so the choice was intentional. Some statues also show traces of paint, and it is possible that the statues were coloured or decorated at some stage, but evidence is limited.
The bodies beneath the heads
The best-known photographs of Easter Island show tall heads rising from the grass on the slopes of Rano Raraku. In the early 20th century, expeditions began to excavate some of them, and later campaigns in the 1950s and again in the 2010s showed that the figures were complete torsos, in some cases extending well below the surface. Sediment washed down from the slope over the centuries had buried them up to the shoulders or beyond, and in some cases the lower sections are much deeper than the visible head.
The excavations also showed that statues had been deliberately set into holes in the slope, where final work was done, which fits the idea that figures were stood upright while they awaited finishing or transport.
Petroglyphs on the backs and chests
When the soil was removed, researchers found that some statues carry carved designs on their backs, shoulders and lower torsos that were not visible before. They include a belt or loincloth design, rings and other geometric patterns, and what are sometimes interpreted as tattoo-like markings. Some figures show a ship-like image, possibly a representation of a European vessel, which would suggest that the carving was done after Europeans arrived, but this reading is debated and the exact images are not always clear.
The designs show that the surface of the moai was richly worked, even though the rock has weathered. They also fit a wider Polynesian practice of tattooing and body decoration as markers of identity and status.
What this means for interpretation
These discoveries matter for two reasons. They show that the moai were not simple, plain monuments, and that the visible heads are only part of a more detailed whole. They also show the value of careful archaeological methods, including excavation and radiocarbon dating of associated material, since information about decoration had been buried for generations and was easy to miss.
It is also worth remembering what is not known. There is no direct evidence of what was said when a pukao was placed, whether it was done in a ceremony, or exactly how the red stone related to status. As with other aspects of the island, the Rapa Nui people are the primary source of knowledge about their heritage, and scholars work alongside them in the national park today. The result is a picture that is richer than the old image of silent stone giants, but still has real gaps.