Thorne first became involved in the Lake Mungo excavations under the archaeologist Jim Bowler in 1969, reconstructing the remains of a skeleton called LM1 — also known as “Mungo Lady”. Five years later, in 1974, he reconstructed Mungo Man. Though the skeletons were then dated at between 28,000 and 34,000 years old, during his reconstruction of “Mungo Lady” Thorne found the bones (the skull in particular) to be thin and frail — similar to the bones of human beings today. Other Australian hominid specimens from the same period had been thick-skulled. It was this discovery that first led him to question the Out of Africa model of human development.