Gustav Heinrich Ralph (often cited as G. H. R.) von Koenigswald (13 November 1902 – 10 July 1982) was a German-Dutch paleontologist and geologist who conducted research on hominins, including Homo erectus. His discoveries and studies of hominid fossils in Java and his studies of other important fossils of south-eastern Asia firmly established his reputation as one of the leading figures of 20th-century paleo-anthropology. Biography Von Koenigswald was born in Berlin in a period of intense interest and rapid growth in the study of evolution. He began his fossil vertebrate collection when he was fifteen with the acquisition of a rhinoceros molar during an excursion to Mauer, Germany. He subsequently studied geology and paleontology at Berlin, Tübingen, Cologne and Munich. Java Von Koenigswald's teacher Ferdinand Broili had good contacts with the Dutch geologists Karl Martin and Reinout Willem van Bemmelen. Through these contacts Von Koenigswald could join the Geological Survey of Java as paleontologist in late 1930. Financed in part through the Carnegie Foundation, he began a systematic survey of the country. Von Koenigswald made his most significant finds in this area of Asia between January 1931 and 1941. At age 33, he announced the discovery of a juvenile calvarium from Mojokerto and assigned it to Pithecanthropus erectus. This identification was criticized by the respected paleontologist Eugène Dubois, but Von Koenigswald did not change his identification. Between 1937 and 1941, a number of important hominid specimens emerged from Java. One of Von Koenigswald's assistants brought him a piece of a Pithecanthropus skull in 1937. Unfortunately, an offer to pay for additional fossils by the piece led to specimens being broken into splinters by native helpers. One skull cap, the first Sangiran calvarium, was an exact duplicate of Dubois' Pithecanthropus calvarium. Other well-known fossils include the Sangiran B mandible, Sangiran 4 including the well-known maxilla with the diastema, and the 1939 and 1941 jaws assigned by Von Koenigswald to Meganthropus paleojavanicus. His work on the fossils of Central Java, particularly from Sangiran, led him to claim that the mammalian remains of the area could be assigned to all three levels of the Pleistocene. All Javanese hominid fossils recovered emerged from three major sets of beds: Pucangan formation, Jetis beds dated to the Early Pleistocene, the Kabuh formation, Trinil beds dated to the Middle Pleistocene, and the Ngandong beds dated to the Upper Pleistocene. Von Koenigswald pointed out that these and other