Editing Java Man (section)

===Date of the fossils===
{{further|Stratigraphy (archaeology)}}
[[Image:The most ancient skeletal remains of man Plate 1.png|thumb|upright=1.5|The locality of the ''Pithecanthropus'' find, on the [[Solo River]], near [[Trinil]], [[Java]]. The two white squares show where the femur (left) and the skullcap (right) were discovered. Their discovery near flowing water was one of the many sources of controversy that surrounded the fossils.]]
[[File:Homo Erectus shell with geometric incisions circa 500,000 BP, Naturalis Biodiversity Center, Netherlands (with detail).jpg|thumb|upright=1.5|[[Pseudodon shell DUB1006-fL]], found near Java Man and dated to circa 500,000 BP, contains the earliest known geometric engravings. From [[Trinil]], [[Java]]. Now in the [[Naturalis Biodiversity Center]], [[Netherlands]].<ref name="Joordens2015">{{Cite journal|last1=Joordens|first1=Josephine C. A.|last2=d’Errico|first2=Francesco|last3=Wesselingh|first3=Frank P.|last4=Munro|first4=Stephen|last5=de Vos|first5=John|last6=Wallinga|first6=Jakob|last7=Ankjærgaard|first7=Christina|last8=Reimann|first8=Tony|last9=Wijbrans|first9=Jan R.|last10=Kuiper|first10=Klaudia F.|last11=Mücher|first11=Herman J.|date=2015|title=Homo erectus at Trinil on Java used shells for tool production and engraving|url=https://www.nature.com/articles/nature13962|journal=Nature|language=en|volume=518|issue=7538|pages=228–231|doi=10.1038/nature13962|pmid=25470048|bibcode=2015Natur.518..228J|s2cid=4461751|issn=1476-4687|url-access=subscription}}</ref>]]

Dubois's complete collection of fossils were transferred between 1895 and 1900 to what is now known as [[Naturalis]], in [[Leiden]] in the [[Netherlands]].<ref>{{cite web|last1=de Vois|first1=John|title=The Dubois collection: a new look at an old collection|url=http://www.repository.naturalis.nl/document/43875 |website=Naturalis.nl|access-date=3 December 2014}}</ref> The main fossil of Java Man, the skullcap cataloged as "Trinil 2", has been dated [[biostratigraphy|biostratigraphically]], that is, by correlating it with a group of fossilized animals (a "[[faunal assemblage]]") found nearby on the same [[horizon (geology)|geological horizon]], which is itself compared with assemblages from other layers and classified chronologically. Ralph von Koenigswald first assigned Java Man to the [[Trinil Fauna]], a faunal assemblage that he composed from several Javanese sites.{{sfn|de Vos|2004|p=275}} He concluded that the skullcap was about 700,000 years old, thus dating from the beginning of the [[Middle Pleistocene]].{{sfnm|1a1=Kaifu et al.|1y=2010|1p=145|2a1=de Vos|2y=2004|2pp=274–75}}

Though this view is still widely accepted, in the 1980s, a group of Dutch [[paleontology|paleontologists]] used Dubois's collection of more than 20,000 animal fossils to reassess the date of the layer in which Java Man was found.{{sfn|Kaifu et al.|2010|p=145}} Using only fossils from Trinil, they called that new faunal assemblage the [[Trinil H. K. Fauna]], in which H. K. stands for ''Haupt Knochenschicht'', or "main fossil-bearing layer".{{sfnm|1a1=de Vos|1y=2004|1pp=275–76 [explanation of the Trinil H. K. Fauna]|2a1=Zaim|2y=2010 |2p=103 [Trinil H. K. Fauna, citing {{harvnb|de Vos et al.|1982}} and {{harvnb|de Vos|Sondaar|1994}}]}} This assessment dates the fossils of Java Man to between 900,000 and 1,000,000 years old.{{sfn|Dennell|2010 |p=155}} On the other hand, work published in 2014 gives a "maximum age of 0.54 ± 0.10 million years and a minimum age of 0.43 ± 0.05 million years" for Ar-Ar and luminescence dating of sediment in human-predated shell material from Trinil.<ref>{{cite journal |title=Homo erectus at Trinil on Java used shells for tool production and engraving |last=Joordens |first=J. C. A. |display-authors=et al.<!--Josephine C A Joordens, Francesco d'Errico, Frank P Wesselingh, Stephen Munro, John de Vos, Jakob Wallinga, Christina Ankjærgaard, Tony Reimann, Jan R Wijbrans, Klaudia F Kuiper, Herman J Mücher, Hélène Coqueugniot, Vincent Prié, Ineke Joosten, Bertil van Os, Anne S Schulp, Michel Panuel, Victoria van der Haas, Wim Lustenhouwer, John J G Reijmer, Wil Roebroeks--> |orig-year= Epub: 2014 Dec 3 |journal=Nature |date=2015-02-12 |volume=518 |issue=7538 |pages=228–31 |pmid=25470048 |doi=10.1038/nature13962|bibcode=2015Natur.518..228J |s2cid=4461751 }}</ref> Work continues on assessing the dating of this complex site.

Other fossils attest to the even earlier presence of ''H. erectus'' in Java. [[Sangiran 2]] (named after [[Sangiran|its discovery site]]) may be as old as 1.66 [[Megaannum|Ma]] (million years). The controversial [[Mojokerto child]], which Carl C. Swisher and [[Garniss Curtis]] once dated to 1.81 ± 0.04 Ma, has now been convincingly re-dated to a maximum age of 1.49 ± 0.13 Ma, that is, 1.49 million years with a margin of error of plus or minus 130,000 years.{{sfnm|Dennell|2009|1p=155 ["The maximum age of this specimen is thus 1.49 million years, and not 1.81 million years, as implied by {{harvnb|Swisher et al.|1994}}"]|Ciochon|2010|2p=112 ["As the relocated discovery bed proved to be ~20&nbsp;m above the horizon that {{harvnb|Swisher et al.|1994}} dated, the skull is certainly younger than had been previously reported" ({{harvnb|Huffman et al.|2006}})"]|Rabett|2012|3p=26 ["the 1994 estimate of its age has now been credibly refuted ({{harvnb|Huffman et al.|2006}})"]|4a1=Dennell|4y=2010|4p=266 ["the recent re-discovery of the precise provenance of the Mojokerto cranium that is now dated to a maximum of 1.49 Ma ({{harvnb|Morwood et al.|2003}}) clarifies long-standing uncertainties over the age of this important specimen"]}}