Publications by authors named "Jason E Lewis"

8 Publications

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Human burials at the Kisese II rockshelter, Tanzania.

Am J Phys Anthropol 2021 Feb 21. Epub 2021 Feb 21.

Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona, USA.

Objectives: The Late Pleistocene and early Holocene in eastern Africa are associated with complex evolutionary and demographic processes that contributed to the population variability observed in the region today. However, there are relatively few human skeletal remains from this time period. Here we describe six individuals from the Kisese II rockshelter in Tanzania that were excavated in 1956, present a radiocarbon date for one of the individuals, and compare craniodental morphological diversity among eastern African populations.

Materials And Methods: This study used standard biometric analyses to assess the age, sex, and stature of the Kisese II individuals. Eastern African craniodental morphological variation was assessed using measures of dental size and a subset of Howells' cranial measurements for the Kisese II individuals as well as early Holocene, early pastoralist, Pastoral Neolithic, and modern African individuals.

Results: Our results suggest a minimum of six individuals from the Kisese II collections with two adults and four juveniles. While the dating for most of the burials is uncertain, one individual is directly radiocarbon dated to ~7.1 ka indicating that at least one burial is early Holocene in age. Craniodental metric comparisons indicate that the Kisese II individuals extend the amount of human morphological diversity among Holocene eastern Africans.

Conclusions: Our findings contribute to a growing body of evidence that Late Pleistocene and early Holocene eastern Africans exhibited relatively high amounts of morphological diversity. However, the Kisese II individuals suggest morphological similarity at localized sites potentially supporting increased regionalization during the early Holocene.
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http://dx.doi.org/10.1002/ajpa.24253DOI Listing
February 2021

Middle and Later Stone Age chronology of Kisese II rockshelter (UNESCO World Heritage Kondoa Rock-Art Sites), Tanzania.

PLoS One 2018 28;13(2):e0192029. Epub 2018 Feb 28.

National Museum of Tanzania, Shaaban Robert Street, Dar es Salaam, Tanzania.

The archaeology of East Africa during the last ~65,000 years plays a central role in debates about the origins and dispersal of modern humans, Homo sapiens. Despite the historical importance of the region to these discussions, reliable chronologies for the nature, tempo, and timing of human behavioral changes seen among Middle Stone Age (MSA) and Later Stone Age (LSA) archaeological assemblages are sparse. The Kisese II rockshelter in the Kondoa region of Tanzania, originally excavated in 1956, preserves a ≥ 6-m-thick archaeological succession that spans the MSA/LSA transition, with lithic artifacts such as Levallois and bladelet cores and backed microliths, the recurrent use of red ochre, and >5,000 ostrich eggshell beads and bead fragments. Twenty-nine radiocarbon dates on ostrich eggshell carbonate make Kisese II one of the most robust chronological sequences for understanding archaeological change over the last ~47,000 years in East Africa. In particular, ostrich eggshell beads and backed microliths appear by 46-42 ka cal BP and occur throughout overlying Late Pleistocene and Holocene strata. Changes in lithic technology suggest an MSA/LSA transition that began 39-34.3 ka, with typical LSA technologies in place by the Last Glacial Maximum. The timing of these changes demonstrates the time-transgressive nature of behavioral innovations often linked to the origins of modern humans, even within a single region of Africa.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0192029PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5830042PMC
March 2018

An earlier origin for stone tool making: implications for cognitive evolution and the transition to Homo.

Philos Trans R Soc Lond B Biol Sci 2016 07;371(1698)

Turkana Basin Institute and Department of Anthropology, Stony Brook University, Stony Brook, NY 11794-4364, USA CNRS, UMR 7055, Préhistoire et Technologie, Université Paris Ouest Nanterre La Défense, 21 allée de l'Université, Nanterre Cedex 92023, France

The discovery of the earliest known stone tools at Lomekwi 3 (LOM3) from West Turkana, Kenya, dated to 3.3 Ma, raises new questions about the mode and tempo of key adaptations in the hominin lineage. The LOM3 tools date to before the earliest known fossils attributed to Homo at 2.8 Ma. They were made and deposited in a more C3 environment than were the earliest Oldowan tools at 2.6 Ma. Their discovery leads to renewed investigation on the timing of the emergence of human-like manipulative capabilities in early hominins and implications for reconstructing cognition. The LOM3 artefacts form part of an emerging paradigm shift in palaeoanthropology, in which: tool-use and tool-making behaviours are not limited to the genus Homo; cranial, post-cranial and behavioural diversity in early Homo is much wider than previously thought; and these evolutionary changes may not have been direct adaptations to living in savannah grassland environments.This article is part of the themed issue 'Major transitions in human evolution'.
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http://dx.doi.org/10.1098/rstb.2015.0233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4920290PMC
July 2016

Major Transitions in Human Evolution: Scientific Discussion Meeting, Royal Society, London, October 22nd-23, 2015.

Authors:
Jason E Lewis

Evol Anthropol 2015 Nov-Dec;24(6):216-8

Turkana Basin Institute and Department of Anthropology, Stony Brook University, Stony Brook, New York, 11794-4364.

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http://dx.doi.org/10.1002/evan.21465DOI Listing
September 2016

3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya.

Nature 2015 May;521(7552):310-5

1] CNRS, UMR 7055, Préhistoire et Technologie, Université Paris Ouest Nanterre La Défense, 21 allée de l'Université, 92023 Nanterre Cedex, France [2] West Turkana Archaeological Project, P.O. Box 40658-00100, Ngara Rd, Nairobi, Kenya.

Human evolutionary scholars have long supposed that the earliest stone tools were made by the genus Homo and that this technological development was directly linked to climate change and the spread of savannah grasslands. New fieldwork in West Turkana, Kenya, has identified evidence of much earlier hominin technological behaviour. We report the discovery of Lomekwi 3, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment. The Lomekwi 3 knappers, with a developing understanding of stone's fracture properties, combined core reduction with battering activities. Given the implications of the Lomekwi 3 assemblage for models aiming to converge environmental change, hominin evolution and technological origins, we propose for it the name 'Lomekwian', which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.
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http://dx.doi.org/10.1038/nature14464DOI Listing
May 2015

The mismeasure of science: Stephen Jay Gould versus Samuel George Morton on skulls and bias.

PLoS Biol 2011 Jun 7;9(6):e1001071. Epub 2011 Jun 7.

Department of Anthropology, Stanford University, Stanford, California, United States of America.

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http://dx.doi.org/10.1371/journal.pbio.1001071DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3110184PMC
June 2011

The protein kinase Cbeta-selective inhibitor, Enzastaurin (LY317615.HCl), suppresses signaling through the AKT pathway, induces apoptosis, and suppresses growth of human colon cancer and glioblastoma xenografts.

Cancer Res 2005 Aug;65(16):7462-9

Lilly Research Labs, Eli Lilly and Company, Indianapolis, Indiana 46285, USA.

Activation of protein kinase Cbeta (PKCbeta) has been repeatedly implicated in tumor-induced angiogenesis. The PKCbeta-selective inhibitor, Enzastaurin (LY317615.HCl), suppresses angiogenesis and was advanced for clinical development based upon this antiangiogenic activity. Activation of PKCbeta has now also been implicated in tumor cell proliferation, apoptosis, and tumor invasiveness. Herein, we show that Enzastaurin has a direct effect on human tumor cells, inducing apoptosis and suppressing the proliferation of cultured tumor cells. Enzastaurin treatment also suppresses the phosphorylation of GSK3betaser9, ribosomal protein S6(S240/244), and AKT(Thr308). Oral dosing with Enzastaurin to yield plasma concentrations similar to those achieved in clinical trials significantly suppresses the growth of human glioblastoma and colon carcinoma xenografts. As in cultured tumor cells, Enzastaurin treatment suppresses the phosphorylation of GSK3beta in these xenograft tumor tissues. Enzastaurin treatment also suppresses GSK3beta phosphorylation to a similar extent in peripheral blood mononuclear cells (PBMCs) from these treated mice. These data show that Enzastaurin has a direct antitumor effect and that Enzastaurin treatment suppresses GSK3beta phosphorylation in both tumor tissue and in PBMCs, suggesting that GSK3beta phosphorylation may serve as a reliable pharmacodynamic marker for Enzastaurin activity. With previously published reports, these data support the notion that Enzastaurin suppresses tumor growth through multiple mechanisms: direct suppression of tumor cell proliferation and the induction of tumor cell death coupled to the indirect effect of suppressing tumor-induced angiogenesis.
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http://dx.doi.org/10.1158/0008-5472.CAN-05-0071DOI Listing
August 2005

The progression of LNCaP human prostate cancer cells to androgen independence involves decreased FOXO3a expression and reduced p27KIP1 promoter transactivation.

Mol Cancer Res 2005 Mar;3(3):163-9

Lilly Research Labs, Cancer Division, Eli Lilly and Company, Lilly Corporate Center, Drop Code 0546, Indianapolis, IN 46285, USA.

The progression of human prostate cancer from the initial androgen-dependent phase to androgen independence involves diminished apoptosis and a release from the cell cycle block triggered by androgen ablation therapy. FOXO transcription factors play a central role in promoting expression of proapoptotic and cell cycle regulatory genes (e.g., FasL and p27KIP1). Reduced FOXO function might, therefore, play a role in androgen-independent progression of human prostate cancer. Herein, we show that FOXO function is compromised in androgen-independent prostate cancer cells (LNAI) versus androgen-dependent LNCaP cells. The FOXO3a protein, the most highly expressed FOXO family member in prostate cancer cells, is hyperphosphorylated in LNAI cells. FOXO3a expression is also markedly reduced in these androgen-independent LNAI cells when compared with parental LNCaP cells. Together, reduced FOXO3a expression coupled to FOXO3a hyperphosphorylation would suppress FOXO transcriptional activity. Accordingly, activity of the FOXO-responsive p27KIP1 promoter is reduced 60% in these LNAI cells when compared with LNCaP cells. Moreover, mutation of a conserved FOXO response element suppresses p27KIP1 promoter activity, substantiating a regulatory role for this FOXO response element in p27KIP1 promoter transactivation. Finally, we show that the activity of a distinct FOXO-responsive promoter, the 3X-IRS promoter, is also reduced in LNAI cells. Collectively, these data show that reduced FOXO3a expression coupled to increased FOXO3a phosphorylation coincide with reduced FOXO-responsive promoter activity in androgen-independent LNAI cells when compared with androgen-dependent LNCaP cells. To the extent that this model reflects human disease, these data suggest that FOXO function may be compromised with androgen-independent progression of human prostate cancer.
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http://dx.doi.org/10.1158/1541-7786.MCR-04-0163DOI Listing
March 2005