Skull IX (Tjg-1993.05) was unearthed from the upper stratigraphic zone (Bapang-AG levels) of the ... more Skull IX (Tjg-1993.05) was unearthed from the upper stratigraphic zone (Bapang-AG levels) of the hominin-bearing sequence in Sangiran. This remarkably complete cranial specimen of Homo erectus from the early Pleistocene of Java preserves substantial portions of the vault and face. However, the distortion present in the original reconstruction has hampered detailed documentation of its morphological characteristics. We here report a new reconstruction of Skull IX that successfully recovers the original morphology and significantly differs from previous reconstructions. Detailed morphological description and the results of initial comparative analyses based on this new reconstruction are provided.The endocranial volume of Skull IX was measured as 870 cc using micro-CT data. The neurocranium of Skull IX is slightly smaller than the so far recorded smallest cranium from this zone, suggesting this individual was female. In most, but not all, aspects of the cranial vault form, details of the external surface structures, and facial morphology, Skull IX exhibits numerous similarities to the other Bapang-AG H. erectus specimens, indicating that it belonged to the Bapang-AG H. erectus population. Drawing on the expanded fossil sample of this chronoregional H. erectus group, we discuss their evolutionary status, degree of sexual dimorphism, and facial morphological variation in Afro-Asian earlier Homo specimens.
A sequence of paleosols in the Solo Basin, Central Java, Indonesia, documents the local and regio... more A sequence of paleosols in the Solo Basin, Central Java, Indonesia, documents the local and regional environments present when Homo erectus spread through Southeast Asia during the early Pleistocene. The earliest human immigrants encountered a low-relief lake-margin landscape dominated by moist grasslands with open woodlands in the driest landscape positions. By 1.5 Ma, large streams filled the lake and the landscape became more riverine in nature, with riparian forests, savanna, and open woodland. Paleosol morphology and carbon isotope values of soil organic matter and pedogenic carbonates indicate a long-term shift toward regional drying or increased duration of the annual dry season through the early Pleistocene. This suggests that an annual dry season associated with monsoon conditions was an important aspect of the paleoclimate in which early humans spread from Africa to Southeast Asia.
Ichnos-an International Journal for Plant and Animal Traces, 2011
Recent fieldwork in the Ombilin Basin of west-central Sumatra resulted in the discovery of two di... more Recent fieldwork in the Ombilin Basin of west-central Sumatra resulted in the discovery of two distinct types of avian footprints, both referable to the ichnogenus Aquatilavipes. The footprints were discovered in the Oligocene Sawahlunto Formation in a creek side outcrop near the Kandi Ombilin Mine. Aquatilavipes wallacei is a small species of Aquatilavipes ( 19 mm wide; 27 mm long) with elongate third digits, wide total divarication angles (120–150°) and inwardly curved peripheral digits. Aquatilavipes ichnospecies A are also small traces (average 21 mm wide; 31 mm long) with elongate third digits and straight to slightly outwardly curved peripheral digits. These traces are similar in morphology to those of small modern shorebirds such as rails (Rallidae), sandpipers (Scolapacidae) or plovers (Charadriinae).The Sawahlunto traces occur in very fine-grained to fine-grained sandstone characterized by low-relief current ripples, many of which exhibit mud-draping. A low diversity invertebrate trace fossil assemblage consisting of Arenicolites, Diplocraterion, Planolites, Monocraterion, Skolithos and Coenobichnus co-occurs with the bird footprints. This succession is interpreted as intertidal sand flats. Probe and peck marks preserved on the same bedding planes as the bird footprints support the interpretation that these birds occupied the Kandi intertidal flats for foraging purposes.
Jablonski and Tyler (1999) announced a new subspecies of colobine monkey based on a fossil partia... more Jablonski and Tyler (1999) announced a new subspecies of colobine monkey based on a fossil partial maxilla from the Sangiran dome. The specimen is easily assigned to a living leaf monkey species—most extant Southeast Asian catarrhines differ only subspecifically from their Middle Pleistocene earliest local fossil ancestors. Yet Jablonski and Tyler (1999) reported an improbable provenance for the specimen; a mass-flow volcanic breccia generally considered late Pliocene in age. We show that the Lower Lahar was laid down amidst a range of paludal habitats and that its deposition predates the appearance of all-but-now extinct, water-tolerant mammals on emergent Java. No other catarrhine fossil has been ascribed to the Lower Lahar, not even hominins, which are the most gregarious members of the group. More probable provenance lies in the upper Sangiran or the lower Bapang formations. Either alternative would associate the specimen with other catarrhine fossils in more tenable Pleistocene environments. We also unravel errors and inconsistencies in the contextual report and in the discussion of dome geochronology. The various radiometric, paleomagnetic, and paleontologic studies cited show a discordance of about 300 Ka (thousand years) across the lithostratigraphic sequence. Plio-Pleistocene biogeographic hypotheses for Java must work with short and long chronologies.
Http Dx Doi Org 10 1080 10420940 2011 634288, Oct 1, 2011
... 2A, C). Recent work on these trace fossil associations has led to the interpretation that the... more ... 2A, C). Recent work on these trace fossil associations has led to the interpretation that these deposits were intertidal flats, possibly associated with an estuarine succession (Zonneveld et al ... These traces also bear some similarities to the ichnogenus Koreanaornis (Kim, 196912. ...
The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the So... more The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the Solo basin of Central Jawa. The dome has yielded nearly 80 Homo erectus fossils, around 50 of which have known findspots. With a hornblende 40Ar/39Ar plateau age of 1.66 ± 0.04 mega-annum (Ma) reportedly associated with two fossils [Swisher, C.C., III, Curtis, G. H., Jacob, T., Getty, A. G., Suprijo, A. & Widiasmoro (1994) Science 263, 1118-1121), the dome offers evidence that early Homo dispersed to East Asia during the earliest Pleistocene. Unfortunately, the hornblende pumice was sampled at Jokotingkir Hill, a central locality with complex lithostratigraphic deformation and dubious specimen provenance. To address the antiquity of Sangiran H. erectus more systematically, we investigate the sedimentary framework and hornblende 40Ar/39Ar age for volcanic deposits in the southeast quadrant of the dome. In this sector, Bapang (Kabuh) sediments have their largest exposure, least deformation, and most complete tephrostratigraphy. At five locations, we identify a sequence of sedimentary cycles in which H. erectus fossils are associated with epiclastic pumice. From sampled pumice, eight hornblende separates produced 40Ar/39Ar plateau ages ranging from 1.51 ± 0.08 Ma at the Bapang/Sangiran Formation contact, to 1.02 ± 0.06 Ma, at a point above the hominin-bearing sequence. The chronological sequence of 40Ar/39Ar ages follows stratigraphic order across the southeast quadrant. An intermediate level yielding four nearly complete crania has an age of about 1.25 Ma.
抄録 The present state of paleontological fossil collections in the Laboratory of Paleontology, Ins... more 抄録 The present state of paleontological fossil collections in the Laboratory of Paleontology, Institute of Technology Bandung, is reported. This laboratory has continued fossil collection activities in various regions of the Indonesian Archipelago since the 1950's. The present ...
Studi perubahan lingkungan pengendapan berdasarkan kajian paleontologi moluska ini diterapkan di ... more Studi perubahan lingkungan pengendapan berdasarkan kajian paleontologi moluska ini diterapkan di daerah penelitian Formasi Kaliwangu – Formasi Citalang, Ujung Jaya, Sumedang, Jawa Barat; Formasi Kalibiuk-Formasi Kaliglagah, Bumiayu, Brebes, Jawa Tengah dan Formasi Bantardawa-Talanggundang, Patikraja, Banyumas, juga di Jawa Tengah. Tujuan penelitian ini menentukan asosiasi moluska dan merekonstruksi lingkungan pengendapan di tiga daerah penelitian. Kemudian dihasilkan perbandingan asosiasi moluska dan lingkungan pengendapan di tiga daerah penelitian. Data yang digunakan adalah distribusi kumpulan fosil moluska hasil determinasi dan analisis semikuantitatif di tiga daerah penelitian. Secara lateral tiga daerah penelitian pada umur Plio-Plistosen mengalami proses pendangkalan dari laut dangkal pada akhir Pliosen menjadi lingkungan non marin memasuki Plistosen. Secara vertikal tiga daerah penelitian menunjukkan proses pendangkalan yang berbeda-beda. Lokasi penelitian F. Kaliwangu, Ujung...
Fossil fishes were first collected from deposits of the Sangkarewang Formation of the Ombilin Bas... more Fossil fishes were first collected from deposits of the Sangkarewang Formation of the Ombilin Basin in Sumatra, Indonesia, in the 1870s, but a comprehensive study of these fishes was not published until almost 50 years later. New material from these deposits was collected in 2009, which included a small anabantoid fish. This fish is not conspecific with any of the material described previously and is here named as a new genus and species. A phylogenetic analysis indicates that the new anabantoid is closely related to Osphronemus among the taxa studied, and we place it in the family Osphronemidae. However, the new fish does not appear to belong to any of the named modern subfamilies, so we leave it incertae sedis in the family. Additionally, the osphronemid subfamilies are not recovered as a monophyletic group. The anabantoid named here and another previously described from the same locality are the only fossil anabantoids known. However, the age of the Sangkarewang Formation is not ...
A stratified paleosol sequence exposed in an open pit mine in central Sumatra provides a record o... more A stratified paleosol sequence exposed in an open pit mine in central Sumatra provides a record of the paleoenvironmental conditions in the lower reaches of a large river system in the late Paleogene (latest Eocene or Oligocene). Morphological, geochemical, and stable isotope data suggest that the sequence represents a mosaic of local environmental conditions changing from estuarine to riverine up section. Weakly expressed soils formed on low-lying estuary surfaces, while more well expressed soils formed on higher, better drained surfaces. Peatlands (coal) with clayey subsoils were along the estuary margins. Well-expressed soils with evidence of clay translocation and chemical weathering become more common higher in the section where alluvial deposits associated with a meandering river are dominant. Stable carbon isotope ratios support a paleolandscape dominated by C3 plants with input by C4 vegetation limited to a few intervals. Finally, whole-rock geochemistry suggests moderate chemical weathering consistent with a tropical locality. This multi-proxy paleoenvironmental reconstruction suggests a highly productive lowland forest environment at this locality in the late Paleogene and provides the first direct examination of the terrestrial environment in Sumatra at this time. The limited fossil record in Island Southeast Asia during this time period is likely a result of poor bone and shell preservation in tropical forest environments combined with a general lack of systematic prospecting. However, our continuing work in this area has produced a relatively diverse assemblage of fossil vertebrates, now including fishes, amphibians, turtles, crocodiles, and mammals, as well as a growing diversity of fossil plants.
Skull IX (Tjg-1993.05) was unearthed from the upper stratigraphic zone (Bapang-AG levels) of the ... more Skull IX (Tjg-1993.05) was unearthed from the upper stratigraphic zone (Bapang-AG levels) of the hominin-bearing sequence in Sangiran. This remarkably complete cranial specimen of Homo erectus from the early Pleistocene of Java preserves substantial portions of the vault and face. However, the distortion present in the original reconstruction has hampered detailed documentation of its morphological characteristics. We here report a new reconstruction of Skull IX that successfully recovers the original morphology and significantly differs from previous reconstructions. Detailed morphological description and the results of initial comparative analyses based on this new reconstruction are provided.The endocranial volume of Skull IX was measured as 870 cc using micro-CT data. The neurocranium of Skull IX is slightly smaller than the so far recorded smallest cranium from this zone, suggesting this individual was female. In most, but not all, aspects of the cranial vault form, details of the external surface structures, and facial morphology, Skull IX exhibits numerous similarities to the other Bapang-AG H. erectus specimens, indicating that it belonged to the Bapang-AG H. erectus population. Drawing on the expanded fossil sample of this chronoregional H. erectus group, we discuss their evolutionary status, degree of sexual dimorphism, and facial morphological variation in Afro-Asian earlier Homo specimens.
A sequence of paleosols in the Solo Basin, Central Java, Indonesia, documents the local and regio... more A sequence of paleosols in the Solo Basin, Central Java, Indonesia, documents the local and regional environments present when Homo erectus spread through Southeast Asia during the early Pleistocene. The earliest human immigrants encountered a low-relief lake-margin landscape dominated by moist grasslands with open woodlands in the driest landscape positions. By 1.5 Ma, large streams filled the lake and the landscape became more riverine in nature, with riparian forests, savanna, and open woodland. Paleosol morphology and carbon isotope values of soil organic matter and pedogenic carbonates indicate a long-term shift toward regional drying or increased duration of the annual dry season through the early Pleistocene. This suggests that an annual dry season associated with monsoon conditions was an important aspect of the paleoclimate in which early humans spread from Africa to Southeast Asia.
Ichnos-an International Journal for Plant and Animal Traces, 2011
Recent fieldwork in the Ombilin Basin of west-central Sumatra resulted in the discovery of two di... more Recent fieldwork in the Ombilin Basin of west-central Sumatra resulted in the discovery of two distinct types of avian footprints, both referable to the ichnogenus Aquatilavipes. The footprints were discovered in the Oligocene Sawahlunto Formation in a creek side outcrop near the Kandi Ombilin Mine. Aquatilavipes wallacei is a small species of Aquatilavipes ( 19 mm wide; 27 mm long) with elongate third digits, wide total divarication angles (120–150°) and inwardly curved peripheral digits. Aquatilavipes ichnospecies A are also small traces (average 21 mm wide; 31 mm long) with elongate third digits and straight to slightly outwardly curved peripheral digits. These traces are similar in morphology to those of small modern shorebirds such as rails (Rallidae), sandpipers (Scolapacidae) or plovers (Charadriinae).The Sawahlunto traces occur in very fine-grained to fine-grained sandstone characterized by low-relief current ripples, many of which exhibit mud-draping. A low diversity invertebrate trace fossil assemblage consisting of Arenicolites, Diplocraterion, Planolites, Monocraterion, Skolithos and Coenobichnus co-occurs with the bird footprints. This succession is interpreted as intertidal sand flats. Probe and peck marks preserved on the same bedding planes as the bird footprints support the interpretation that these birds occupied the Kandi intertidal flats for foraging purposes.
Jablonski and Tyler (1999) announced a new subspecies of colobine monkey based on a fossil partia... more Jablonski and Tyler (1999) announced a new subspecies of colobine monkey based on a fossil partial maxilla from the Sangiran dome. The specimen is easily assigned to a living leaf monkey species—most extant Southeast Asian catarrhines differ only subspecifically from their Middle Pleistocene earliest local fossil ancestors. Yet Jablonski and Tyler (1999) reported an improbable provenance for the specimen; a mass-flow volcanic breccia generally considered late Pliocene in age. We show that the Lower Lahar was laid down amidst a range of paludal habitats and that its deposition predates the appearance of all-but-now extinct, water-tolerant mammals on emergent Java. No other catarrhine fossil has been ascribed to the Lower Lahar, not even hominins, which are the most gregarious members of the group. More probable provenance lies in the upper Sangiran or the lower Bapang formations. Either alternative would associate the specimen with other catarrhine fossils in more tenable Pleistocene environments. We also unravel errors and inconsistencies in the contextual report and in the discussion of dome geochronology. The various radiometric, paleomagnetic, and paleontologic studies cited show a discordance of about 300 Ka (thousand years) across the lithostratigraphic sequence. Plio-Pleistocene biogeographic hypotheses for Java must work with short and long chronologies.
Http Dx Doi Org 10 1080 10420940 2011 634288, Oct 1, 2011
... 2A, C). Recent work on these trace fossil associations has led to the interpretation that the... more ... 2A, C). Recent work on these trace fossil associations has led to the interpretation that these deposits were intertidal flats, possibly associated with an estuarine succession (Zonneveld et al ... These traces also bear some similarities to the ichnogenus Koreanaornis (Kim, 196912. ...
The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the So... more The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the Solo basin of Central Jawa. The dome has yielded nearly 80 Homo erectus fossils, around 50 of which have known findspots. With a hornblende 40Ar/39Ar plateau age of 1.66 ± 0.04 mega-annum (Ma) reportedly associated with two fossils [Swisher, C.C., III, Curtis, G. H., Jacob, T., Getty, A. G., Suprijo, A. & Widiasmoro (1994) Science 263, 1118-1121), the dome offers evidence that early Homo dispersed to East Asia during the earliest Pleistocene. Unfortunately, the hornblende pumice was sampled at Jokotingkir Hill, a central locality with complex lithostratigraphic deformation and dubious specimen provenance. To address the antiquity of Sangiran H. erectus more systematically, we investigate the sedimentary framework and hornblende 40Ar/39Ar age for volcanic deposits in the southeast quadrant of the dome. In this sector, Bapang (Kabuh) sediments have their largest exposure, least deformation, and most complete tephrostratigraphy. At five locations, we identify a sequence of sedimentary cycles in which H. erectus fossils are associated with epiclastic pumice. From sampled pumice, eight hornblende separates produced 40Ar/39Ar plateau ages ranging from 1.51 ± 0.08 Ma at the Bapang/Sangiran Formation contact, to 1.02 ± 0.06 Ma, at a point above the hominin-bearing sequence. The chronological sequence of 40Ar/39Ar ages follows stratigraphic order across the southeast quadrant. An intermediate level yielding four nearly complete crania has an age of about 1.25 Ma.
抄録 The present state of paleontological fossil collections in the Laboratory of Paleontology, Ins... more 抄録 The present state of paleontological fossil collections in the Laboratory of Paleontology, Institute of Technology Bandung, is reported. This laboratory has continued fossil collection activities in various regions of the Indonesian Archipelago since the 1950's. The present ...
Studi perubahan lingkungan pengendapan berdasarkan kajian paleontologi moluska ini diterapkan di ... more Studi perubahan lingkungan pengendapan berdasarkan kajian paleontologi moluska ini diterapkan di daerah penelitian Formasi Kaliwangu – Formasi Citalang, Ujung Jaya, Sumedang, Jawa Barat; Formasi Kalibiuk-Formasi Kaliglagah, Bumiayu, Brebes, Jawa Tengah dan Formasi Bantardawa-Talanggundang, Patikraja, Banyumas, juga di Jawa Tengah. Tujuan penelitian ini menentukan asosiasi moluska dan merekonstruksi lingkungan pengendapan di tiga daerah penelitian. Kemudian dihasilkan perbandingan asosiasi moluska dan lingkungan pengendapan di tiga daerah penelitian. Data yang digunakan adalah distribusi kumpulan fosil moluska hasil determinasi dan analisis semikuantitatif di tiga daerah penelitian. Secara lateral tiga daerah penelitian pada umur Plio-Plistosen mengalami proses pendangkalan dari laut dangkal pada akhir Pliosen menjadi lingkungan non marin memasuki Plistosen. Secara vertikal tiga daerah penelitian menunjukkan proses pendangkalan yang berbeda-beda. Lokasi penelitian F. Kaliwangu, Ujung...
Fossil fishes were first collected from deposits of the Sangkarewang Formation of the Ombilin Bas... more Fossil fishes were first collected from deposits of the Sangkarewang Formation of the Ombilin Basin in Sumatra, Indonesia, in the 1870s, but a comprehensive study of these fishes was not published until almost 50 years later. New material from these deposits was collected in 2009, which included a small anabantoid fish. This fish is not conspecific with any of the material described previously and is here named as a new genus and species. A phylogenetic analysis indicates that the new anabantoid is closely related to Osphronemus among the taxa studied, and we place it in the family Osphronemidae. However, the new fish does not appear to belong to any of the named modern subfamilies, so we leave it incertae sedis in the family. Additionally, the osphronemid subfamilies are not recovered as a monophyletic group. The anabantoid named here and another previously described from the same locality are the only fossil anabantoids known. However, the age of the Sangkarewang Formation is not ...
A stratified paleosol sequence exposed in an open pit mine in central Sumatra provides a record o... more A stratified paleosol sequence exposed in an open pit mine in central Sumatra provides a record of the paleoenvironmental conditions in the lower reaches of a large river system in the late Paleogene (latest Eocene or Oligocene). Morphological, geochemical, and stable isotope data suggest that the sequence represents a mosaic of local environmental conditions changing from estuarine to riverine up section. Weakly expressed soils formed on low-lying estuary surfaces, while more well expressed soils formed on higher, better drained surfaces. Peatlands (coal) with clayey subsoils were along the estuary margins. Well-expressed soils with evidence of clay translocation and chemical weathering become more common higher in the section where alluvial deposits associated with a meandering river are dominant. Stable carbon isotope ratios support a paleolandscape dominated by C3 plants with input by C4 vegetation limited to a few intervals. Finally, whole-rock geochemistry suggests moderate chemical weathering consistent with a tropical locality. This multi-proxy paleoenvironmental reconstruction suggests a highly productive lowland forest environment at this locality in the late Paleogene and provides the first direct examination of the terrestrial environment in Sumatra at this time. The limited fossil record in Island Southeast Asia during this time period is likely a result of poor bone and shell preservation in tropical forest environments combined with a general lack of systematic prospecting. However, our continuing work in this area has produced a relatively diverse assemblage of fossil vertebrates, now including fishes, amphibians, turtles, crocodiles, and mammals, as well as a growing diversity of fossil plants.
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