PITHECANTHROPUS ERECTUS
About 1.8 Ma, the first group of ancient human ancestors, Homo erectus,
migrated from Africa to Eurasia(2014MatsubayashiK). As they spread, part of the
population colonized the islands of Southwest Asia, in particular the Malay
Archipelago. In 1891-1892, on the island of Java, Eugène Dubois (1858-1940)
excavated the remains of an «old female» whom he named Pithecanthropus erectus
(2004DeVosJ). Anthropologists also call this individual: Anthropopithecus
erectus, Homo erectus, and Java Man (2000SwisherIIICC_LewinR; 2024PopE_SpoorF). The
discovered skull fragment and molar allowed to reconstruct the appearance of
Pithecanthropus erectus.
 |
| Early Pithecanthropus from Java Island (Sangiran-17), about 1 million years old, reconstruction by M.L. Butovskaya; State Darwin Museum (Moscow), photo by the author. |
The soil layer that preserved the mentioned Homo erectus specimen is
dated in the range from 0.54±0.10 to 0.43±0.05 Ma (2015JoordensJC_RoebroeksW).
A notable component of the find was a fragment of the femur.
 |
| Femur and teeth of Pithecanthropus from Java Island; State Darwin Museum (Moscow), photo by the author. |
At the same time, the fossil fragment had a huge ossification at the
attachment site of the short adductor muscle, m. adductor brevis (sketchfab.com). Such benign neoplasms are usually the result of the
replacement of hematoma or muscle tissue with fibrous tissue, which later
transforms into bone tissue. Hemorrhage and calcification of the adductor
muscle group in Java Man occurred either from a direct blow to the medial
surface of the thigh or due to chronic microtraumatization with ruptures of
muscle fibers. The latter variant appears in the literature as «adductor
insertion avulsion syndrome» causing traction periostitis, a bone reaction to
stress, and a hip fracture (2001Anderson MW_DussaultRG).
Pithecanthropus experienced pain and limited movement in the hip joint,
which complicated stalking prey during hunting, climbing trees for fruit, and
walking. Its ability to move on two pelvic limbs is evidenced by the fossa of
the head of the femur - the attachment area of the ligamentum capitis femoris
(LCF). Based on the size and depth of the femoral head fossa, the LCF of Pithecanthropus of Java was a powerful structure.
It seems to us that it was adapted to withstand significant tensile (pulling
out of the bone) loads when jumping and running during hunting.
 |
| Femoral head and fovea capitis of the Pithecanthropus of Java; State Darwin Museum (Moscow), photo by the author. |
References
Matsubayashi K. Geriatric issues from the standpoint of human evolution. Geriatrics & Gerontology International. 2014;14(4)731-4. [pmc.ncbi.nlm.nih.gov]
De Vos J. The Dubois collection: a new look at an old collection. Scripta Geologica. 2004;Special Issue,4:267-85. [repository.naturalis.nl]
Swisher III CC, Curtis GH, Lewin R. Java Man: How Two Geologists Changed Our Understanding of Human Evolution. Chicago: University of Chicago Press, 2000. [books.google]
Pop E, Noerwidi S, Spoor F. Naming Homo erectus: A review. Journal of Human Evolution. 2024;190:103516. [sciencedirect.com]
Joordens JC, d’Errico F, Wesselingh FP, Munro S, De Vos J, Wallinga J, ... Roebroeks W. Homo erectus at Trinil on Java used shells for tool production and engraving. Nature. 2015;518(7538)228-31. [nature.com]
Anderson MW, Kaplan PA, Dussault RG. Adductor insertion avulsion syndrome (thigh splints): spectrum of MR imaging features. AJR Am J Roentgenol. 2001;177:673-5. [ajronline.org]
Keywords
ligamentum capitis femoris, ligamentum teres, ligament of head of femur, doctrine, homo, pithecanthropus
The original text in Russian is available at the link: Pithecanthropus erectus
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