Kathleen Nicoll

The Climate and Environment of Byzantine Anatolia: Integrating Science, History, and Archaeology

The integration of high-resolution archaeological, textual, and environmental data with longer-term, low-resolution data affords greater precision in identifying some of the causal relationships underlying societal change. Regional and microregional case studies about the Byzantine world—in particular, Anatolia, which for several centuries was the heart of that world—reveal many of the difficulties that researchers face when attempting to assess the influence of environmental factors on human society. The Anatolian case challenges a number of assumptions about the impact of climatic factors on socio-political organization and medium-term historical evolution, highlighting the importance of further collaboration between historians, archaeologists, and climate scientists.

An Acheulian site near Bir Kiseiba in the Darb el Arba'in Desert, Egypt

A small concentration of Acheulian cleavers and handaxes within the driest region on Earth adds to the increasing evidence that the eastern Sahara was considerably more verdant during the Middle Pleistocene than it is today. The similarities to stone artifact assemblages of Acheulian sites in sub-Saharan Africa and in the Levant support the evidence for the movement of hominids, utilizing the Kombewa lithic technology, between Africa and the Middle East during the Middle Pleistocene.

Arguments and Evidence Against a Younger Dryas Impact Event

We present arguments and evidence against the hypothesis that a large impact or airburst caused a significant abrupt climate change, extinction event, and termination of the Clovis culture at 12.9 ka. It should be noted that there is not one single Younger Dryas (YD) impact hypothesis but several that conflict with one another regarding many significant details. Fragmentation and explosion mechanisms proposed for some of the versions do not conserve energy or momentum, no physics-based model has been presented to support the various concepts, and existing physical models contradict them. In addition, the a priori odds of the impact of a >4 km comet in the prescribed configuration on the Laurentide Ice Sheet during the specified time period are infinitesimal, about one in 10 15 . There are three broad classes of counterarguments. First, evidence for an impact is lacking. No impact craters of the appropriate size and age are known, and no unambiguously shocked material or other features diagnostic of impact have been found in YD sediments. Second, the climatological, paleontological, and archeological events that the YD impact proponents are attempting to explain are not unique, are arguably misinterpreted by the proponents, have large chronological uncertainties, are not necessarily coupled, and do not require an impact. Third, we believe that proponents have misinterpreted some of the evidence used to argue for an impact, and several independent researchers have been unable to reproduce reported results. This is compounded by the observation of contamination in a purported YD sample with modern carbon.

Landscape development within a young collision zone: implications for post-Tethyan evolution of the Upper Tigris River system in southeastern Turkey

The geomorphic evolution of the upper basin of the Tigris (Dicle) River in southeastern Turkey reflects the interplay of surface processes and the development of topographic relief and lithospheric deformation since the closing of the Southern Neo-Tethyan (formerly Bitlis) Ocean. The study of the Tigris system is a proxy for understanding the deep crustal processes associated with the active Alpine–Himalayan mountain belt. The drainage morphology is linked to the uplift of the eastern Taurus Mountains and deformation of the Arabian foreland system following continent–continent collision. Initial review of landscape features at aerial and field scales confirms that the evolution of the Tigris has been complex, and that valley morphology varies by reach. Within the headwater reach, the Tigris is a transverse river system that flows across metamorphic rocks of the Bitlis–Zagros Suture Zone. Ongoing deformation in the Lake Hazar region bounded by the East Anatolian Fault Zone controls the topographic divide between the watershed draining north to the Euphrates and south to the Tigris. At the junction of the Arabian Plate, the river may be viewed as an antecedent stream system that developed since the Miocene. In the reach near Diyarbakir, valley development (and possibly incision) has been influenced by recent effusive volcanism. East of Diyarbakir, evaporitic karst processes are currently causing sapping, piping, and subsurface collapse as well as valley widening, which is concentrated in folds paralleling the suture zone and orogen to the north. The evolution of the Upper Tigris over the past 13 Myr can be reconstructed as a function of vertical movement (e.g. base-level changes, tectonic uplift, doming, downwarp, and sagging), horizontal deformation (e.g. folding, faulting, compression, and extension), volcanism, weathering, and erosion (e.g. dissolution processes, karstic erosion, and sapping). It is important to assess the first-order tectonic controls on the evolving fluvial systematics of the Tigris so that its sedimentary and geomorphic records can be used to reconstruct hydroclimatic changes affecting this part of the Near East during antiquity.

Age models and the Younger Dryas Impact Hypothesis

Israde-Alcantara et al. (1) drew on interpretations of a core from Lake Cuitzeo, Mexico to support the Younger Dryas (YD) Impact Hypothesis. A key aspect of their study was identifying and dating the YD interval in the sediments. The authors stated that they recovered impact indicators from a 10-cm-thick zone dating to 12.9 kcal BP but provided no direct numerical age control or chronological uncertainties for this interval. Depending on the carbon sources, 14C ages of bulk lake sediment can be offset by several centuries (2). However, even though the study used bulk 14C dates, no offset was quantified. Dating of the section was accomplished by interpolating through >1 m of undated sediment, because the six dates in that interval were rejected. Even so, the rejected dates were in stratigraphic order, and there seems no a priori basis to exclude them. Their age model was anchored by a tephra layer identified as the Cieneguillas rhyolitic tephra, dated elsewhere as ∼31 kcal BP (3), but no geochemical evidence was provided to support this tephra identification.

The Upper Tigris Archaeological Research Project (UTARP)

Introduction During the summer of 2005 members of the Upper Tigris Archaeological Research Project (UTARP) undertook a sixth season of archaeological field work at the site of Kenan Tepe in the Upper Tigris River region of southeastern Turkey. This research took place between May 13 and July 4, 2005. Research was funded by generous grants from the Curtiss T. and Mary G. Brennan Foundation in collaboration with the University of Utah and the United States National Endowment for the Humanities. Funding from NEH covered the project infrastructure (including rent for the project dighouse, the cost of the project van and driver and the project cook) and costs associated with the excavation of trenches where we expected to discover remains dating to the Late Chalcolithic period. Funds from the Brennan Foundation and the University of Utah were directed exclusively to trenches that we expected to yield data from the Ubaid period. In this report to the Curtiss T. and Mary G. Brennan Foundation and the College of Humanities at the University of Utah, I will briefly outline the Ubaid research conducted during the 2005 field season. After a short introduction I will discuss each of the Ubaid excavation units. I will conclude with a few preliminary observations about the nature of Ubaid occupation at Kenan Tepe. First I would like to make a few remarks about the both the research and the logistics of UTARP’s 2005 field season. In archaeological terms the 2005 field season was perhaps our most productive and most interesting season yet. We excavated two superimposed domestic structures, found part

Incomplete Bayesian model rejects contradictory radiocarbon data for being contradictory

Kennett et al. (1) apply a Bayesian chronological model in an effort to support the hypothesis of Firestone et al. (2) that “a major cosmic episode of multiple airbursts/impacts occurred at 12,800 ± 300 [B.P.].” Bayesian modeling is a powerful tool because it is intended to incorporate and account for all available evidence. However, Kennett et al. (1) do not include radiocarbon data by Boslough et al. (3) and others in their new analysis because they found it contradictory, undermining their own objectives. Moreover, Kennett et al. (1) dismiss issues raised by the key data they omitted for being contradictory rather than incorporating it their Bayesian model.

Geoarchaeological Perspectives on Holocene Climate Change as a Civilizing Factor In the Egyptian Sahara

Throughout prehistory, rapid hydroclimatic changes (“wet-dry”cycles) played a key role in landscape habitability and resource availability in the Egyptian Sahara. As water sources waned during episodes of Holocene drought, people developed various subsistence strategies, including opportunistic hunting of small animals and food production such as gathering, transhumance, and livestock rearing. The geoarchaeological record of the Neolithic culture at Nabta Playa ~100 km west of the Nile Valley suggests that Holocene droughts were a civilizing factor; migrations toward water-fostered acculturation and social complexity, which is evident in burials, ceremonial centers, and solar calendars built at Nabta. The ultimate resilience strategy of the desert dwellers was relocation to the Nile Valley and the transition to agriculture after 5300 calendar years B.P.

Paleoecological changes at Lake Cuitzeo were not consistent with an extraterrestrial impact

Israde-Alcantara et al. (1) reported evidence for the Younger Dryas (YD) Impact Hypothesis (YDIH), which proposes that an extraterrestrial impact triggered the YD (2). Although most YDIH research has focused on the impact event itself, YDIH proponents, as in this article, have argued that the ecological consequences included “widespread biomass burning, and contributed to the extinction of Late Pleistocene megafauna and to major declines in human populations.” To fully test the YDIH, the authors must evaluate evidence and mechanisms for the ecological consequences of an impact. We believe there are flaws in both the interpretation of the paleoecological evidence reviewed by Israde-Alcantara et al. and in its application in testing the YDIH.

SALINE LAKES … A LOGICAL STEP IN EXPLORING HABITABILITY OF “THE FINAL FRONTIER”

Studies of modern biota in Earths extreme environments provide valuable insights about microbial life as preserved in the rock record since the Archean (e.g., Knoll 1985; Brocks et al. 1999; Xiong et al. 2000; Eigenbrode and Freeman 2006; Kaufmann et al. 2007; Brake and Hasiotis 2008). Paradigms of evolutionary biology on Earth extend to astrobiology, a field that studies the origin, evolution and distribution of extraterrestrial life forms. The goal of space exploration in its pursuit to find life is to “follow the water” (NASA 2008). As such, the presence of “the universal solvent”—water—is key to assessing the habitability of Mars and other planets (e.g., Rothschild 1990; Malin and Edgett 2003; Squyres et al. 2004; Lineweaver et al. 2004; Bullock 2005). Many recent publications present telescope and space probe data as evidence for the presence of watery biomes in our solar system, and beyond. Life possibly existed in the paleowater body at Endeavour Crater, Mars (Arvidson et al. 2014). Saltwater oceans hypothetically exist below the ice on the Saturn moon Enceladus (e.g., Postberg et al. 2009, 2011). On Europa, the innermost icy satellite of Jupiter, potential biomes include brines made of …