September 10, 1788 (a Wednesday)

Jacques Boucher de Crèvecœur de Perthes

On this date, the French geologist and archaeologist Jacques Boucher de Crèvecœur de Perthes was born. His discovery in 1846 of whole handaxes, tools, and fragments embedded in and scattered about the fossilized bones of extinct mammals in the Somme River valley showed that man existed at least as early as the ancient creatures. He announced his discovery in the first volume of a work he published in 1847, Antiquites Celtiques Et Antediluviennes (Celtic and pre-Flood Antiquities).

The very title of his book showed that Boucher de Perthes at first regarded these implements and weapons as having belonged to men overwhelmed at the Deluge of Noah; but it was soon seen that they were something very different. Being found in terraces at great heights above the Somme River indicated that they must have been deposited there at a time when the river system of northern France was vastly different from anything known within the historic period. This would have required a series of great geological changes since the time when these implements were made, disproving the prevailing theologically-based idea that 4004 B.C. was the year of the creation of man.

The type of handaxe discovered by Boucher de Perthes.

Although Boucher de Perthes was the first to establish that Europe had been populated by early man in the Pleistocene or early Quaternary period, he himself was not able to pinpoint the precise period because the scientific frame of reference did not then exist. Today, the handaxes of the Somme River district are widely accepted to be at least 500,000 years old and thus the product of Neandertal populations, while some authorities think they may be as old as one million years and therefore associated with Homo erectus.

January 28, 1858 (a Thursday)

Eugene Dubois

On this date, the Dutch surgeon, anthropologist, anatomist, and paleontologist Eugene Dubois was born. Dubois vowed to prove Darwin right by finding “the missing link”, the evolutionary connection between apes and modern humans. In October of 1891, while digging into fossil-rich ash and river sediments on the island of Java in what is now Indonesia, he found skeletal remains of what he later named Pithecanthropus erectus. The name meant “ape-human which stood upright.” Now known as Homo erectus or informally as “Java Man”, it is considered to be the direct ancestor of modern humans. Dubois was the first person to ever deliberately search for fossils of human ancestors. Only a handful of fossil humans had already been discovered, all Neandertals, and those were by chance.

The Homo erectus skullcap (Trinil 2, holotype) discovered by Dubois.

Early African Homo erectus fossils (sometimes called Homo ergaster) are the oldest known early humans to have possessed modern human-like body proportions with relatively elongated legs and shorter arms compared to the size of the torso. These features are considered adaptations to a life lived on the ground, indicating the loss of earlier tree-climbing adaptations, with the ability to walk and possibly run long distances.

The most complete fossil individual of this species is known as the “Turkana Boy” — a well-preserved skeleton (though minus almost all the hand and foot bones), dated around 1.6 million years old. Microscopic study of the teeth indicates that he grew up at a growth rate similar to that of a great ape. There is fossil evidence that this species cared for old and weak individuals. The appearance of Homo erectus in the fossil record is often associated with the earliest handaxes, the first major innovation in stone tool technology.

Generally considered to have been the first species to have expanded beyond Africa, Homo erectus is considered a highly variable species, spread over two continents (it’s not certain whether it reached Europe), and possibly the longest lived early human species — about nine times as long as our own species, Homo sapiens, has been around.

December 19, 1944 (a Tuesday)

Richard E. Leakey

On this date, the Kenyan physical anthropologist and paleontologist Richard E. Leakey was born. Leakey, second of three sons of noted anthropologists Louis Leakey and Mary Leakey, decided at an early age that he wanted nothing to do with paleoanthropology and started a expedition business. In 1964, he led an expedition to a fossil site which sparked his interest in paleontology. Since then he has been responsible for extensive fossil finds of human ancestral forms in East Africa, including a Homo habilis skull found in 1972, and a Homo erectus skull found in 1975. His discoveries showed that man’s ancestors used tools, which shows intelligence, and lived in eastern Africa at least 3 million years ago – almost doubling the previously accepted age of human origins.