Olmec colossal heads vary in height from 1 @.@ 47 to 3 @.@ 4 metres ( 4 @.@ 8 to 11 @.@ 2 ft ) and weigh between 6 and 50 tons . All of the Olmec colossal heads depict mature men with flat noses and fleshy cheeks ; the eyes tend to be slightly crossed . The general physical characteristics of the heads are of a type that is still common among people in the Olmec region in modern times . The backs of the heads are often flat , as if the monuments were originally placed against a wall . All examples of Olmec colossal heads wear distinctive headdresses that probably represent cloth or animal hide originals . Some examples have a tied knot at the back of the head , and some are decorated with feathers . A head from La Venta is decorated with the head of a bird . There are similarities between the headdresses on some of the heads that has led to speculation that specific headdresses may represent different dynasties , or perhaps identify specific rulers . Most of the heads wear large earspools inserted into the ear lobes .