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In a recent opinion piece, Denis Duboule has claimed that the increasing shift towards systems biology is driving evolutionary and developmental biology apart, and that a true reunification of these two disciplines within the framework of evolutionary developmental biology (EvoDevo) may easily take another 100 years. He identifies methodological, epistemological,

In a recent opinion piece, Denis Duboule has claimed that the increasing shift towards systems biology is driving evolutionary and developmental biology apart, and that a true reunification of these two disciplines within the framework of evolutionary developmental biology (EvoDevo) may easily take another 100 years. He identifies methodological, epistemological, and social differences as causes for this supposed separation. Our article provides a contrasting view. We argue that Duboule’s prediction is based on a one-sided understanding of systems biology as a science that is only interested in functional, not evolutionary, aspects of biological processes. Instead, we propose a research program for an evolutionary systems biology, which is based on local exploration of the configuration space in evolving developmental systems. We call this approach—which is based on reverse engineering, simulation, and mathematical analysis—the natural history of configuration space. We discuss a number of illustrative examples that demonstrate the past success of local exploration, as opposed to global mapping, in different biological contexts. We argue that this pragmatic mode of inquiry can be extended and applied to the mathematical analysis of the developmental repertoire and evolutionary potential of evolving developmental mechanisms and that evolutionary systems biology so conceived provides a pragmatic epistemological framework for the EvoDevo synthesis.

ContributorsJaeger, Johannes (Author) / Laubichler, Manfred (Author) / Callebaut, Werner (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-02-17
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It is not known whether environmental O2 levels increased in a linear fashion or fluctuated dynamically between the evolution of oxygenic photosynthesis and the later Great Oxidation Event. New rhenium-osmium isotope data from the late Archean Mount McRae Shale, Western Australia, reveal a transient episode of oxidative continental weathering more

It is not known whether environmental O2 levels increased in a linear fashion or fluctuated dynamically between the evolution of oxygenic photosynthesis and the later Great Oxidation Event. New rhenium-osmium isotope data from the late Archean Mount McRae Shale, Western Australia, reveal a transient episode of oxidative continental weathering more than 50 million years before the onset of the Great Oxidation Event. A depositional age of 2495 ± 14 million years and an initial 187Os/188Os of 0.34 ± 0.19 were obtained for rhenium- and molybdenum-rich black shales. The initial 187Os/188Os is higher than the mantle/extraterrestrial value of 0.11, pointing to mild environmental oxygenation and oxidative mobilization of rhenium, molybdenum, and radiogenic osmium from the upper continental crust and to contemporaneous transport of these metals to seawater. By contrast, stratigraphically overlying black shales are rhenium- and molybdenum-poor and have a mantle-like initial 187Os/188Os of 0.06 ± 0.09, indicating a reduced continental flux of rhenium, molybdenum, and osmium to seawater because of a drop in environmental O[subscript 2] levels. Transient oxygenation events, like the one captured by the Mount McRae Shale, probably separated intervals of less oxygenated conditions during the late Archean.

ContributorsKendall, Brian (Author) / Creaser, Robert A. (Author) / Reinhard, Christopher T. (Author) / Lyons, Timothy W. (Author) / Anbar, Ariel (Author) / College of Liberal Arts and Sciences (Contributor)
Created2015-11-20
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In this synthesis, we hope to accomplish two things: 1) reflect on how the analysis of the new archaeological cases presented in this special feature adds to previous case studies by revisiting a set of propositions reported in a 2006 special feature, and 2) reflect on four main ideas that

In this synthesis, we hope to accomplish two things: 1) reflect on how the analysis of the new archaeological cases presented in this special feature adds to previous case studies by revisiting a set of propositions reported in a 2006 special feature, and 2) reflect on four main ideas that are more specific to the archaeological cases: i) societal choices are influenced by robustness–vulnerability trade-offs, ii) there is interplay between robustness–vulnerability trade-offs and robustness–performance trade-offs, iii) societies often get locked in to particular strategies, and iv) multiple positive feedbacks escalate the perceived cost of societal change. We then discuss whether these lock-in traps can be prevented or whether the risks associated with them can be mitigated. We conclude by highlighting how these long-term historical studies can help us to understand current society, societal practices, and the nexus between ecology and society.

ContributorsSchoon, Michael (Author) / Fabricius, Christo (Author) / Anderies, John (Author) / Nelson, Margaret (Author) / College of Liberal Arts and Sciences (Contributor)
Created2011
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For at least the past 8000 years, small-scale farmers in semi-arid environments have had to mitigate shortfalls in crop production due to variation in precipitation and stream flow. To reduce their vulnerability to a shortfall in their food supply, small-scale farmers developed short-term strategies, including storage and community-scale sharing, to

For at least the past 8000 years, small-scale farmers in semi-arid environments have had to mitigate shortfalls in crop production due to variation in precipitation and stream flow. To reduce their vulnerability to a shortfall in their food supply, small-scale farmers developed short-term strategies, including storage and community-scale sharing, to mitigate inter-annual variation in crop production, and long-term strategies, such as migration, to mitigate the effects of sustained droughts. We use the archaeological and paleoclimatic records from A.D. 900-1600 in two regions of the American Southwest to explore the nature of variation in the availability of water for crops, and the strategies that enhanced the resilience of prehistoric agricultural production to climatic variation. Drawing on information concerning contemporary small-scale farming in semi-arid environments, we then suggest that the risk coping and mitigation strategies that have endured for millennia are relevant to enhancing the resilience of contemporary farmers’ livelihoods to environmental and economic perturbations.

ContributorsSpielmann, Katherine (Author) / Nelson, Margaret (Author) / Ingram, Scott (Author) / Peeples, Matthew (Author) / College of Liberal Arts and Sciences (Contributor)
Created2011
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The value of “diversity” in social and ecological systems is frequently asserted in academic and policy literature. Diversity is thought to enhance the resilience of social-ecological systems to varied and potentially uncertain future conditions. Yet there are trade-offs; diversity in ecological and social domains has costs as well as benefits.

The value of “diversity” in social and ecological systems is frequently asserted in academic and policy literature. Diversity is thought to enhance the resilience of social-ecological systems to varied and potentially uncertain future conditions. Yet there are trade-offs; diversity in ecological and social domains has costs as well as benefits. In this paper, we examine social diversity, specifically its costs and benefits in terms of decision making in middle range or tribal societies, using archaeological evidence spanning seven centuries from four regions of the U.S. Southwest. In these nonstate societies, social diversity may detract from the capacity for collective action. We ask whether as population density increases, making collective action increasingly difficult, social diversity declines. Further, we trace the cases of low diversity and high population density across our long-temporal sequences to see how they associate with the most dramatic transformations. This latter analysis is inspired by the claim in resilience literature that reduction of diversity may contribute to reduction in resilience to varied conditions. Using archaeological data, we examine social diversity and conformity through the material culture (pottery styles) of past societies. Our research contributes to an enhanced understanding of how population density may limit social diversity and suggests the role that this association may play in some contexts of dramatic social transformation.

ContributorsNelson, Margaret (Author) / Hegmon, Michelle (Author) / Kulow, Stephanie (Author) / Peeples, Matthew (Author) / Kintigh, Keith (Author) / Kinzig, Ann (Author) / College of Liberal Arts and Sciences (Contributor)
Created2011
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What relationships can be understood between resilience and vulnerability in social-ecological systems? In particular, what vulnerabilities are exacerbated or ameliorated by different sets of social practices associated with water management? These questions have been examined primarily through the study of contemporary or recent historic cases. Archaeology extends scientific observation beyond

What relationships can be understood between resilience and vulnerability in social-ecological systems? In particular, what vulnerabilities are exacerbated or ameliorated by different sets of social practices associated with water management? These questions have been examined primarily through the study of contemporary or recent historic cases. Archaeology extends scientific observation beyond all social memory and can thus illuminate interactions occurring over centuries or millennia. We examined trade-offs of resilience and vulnerability in the changing social, technological, and environmental contexts of three long-term, pre-Hispanic sequences in the U.S. Southwest: the Mimbres area in southwestern New Mexico (AD 650–1450), the Zuni area in northern New Mexico (AD 850–1540), and the Hohokam area in central Arizona (AD 700–1450). In all three arid landscapes, people relied on agricultural systems that depended on physical and social infrastructure that diverted adequate water to agricultural soils. However, investments in infrastructure varied across the cases, as did local environmental conditions. Zuni farming employed a variety of small-scale water control strategies, including centuries of reliance on small runoff agricultural systems; Mimbres fields were primarily watered by small-scale canals feeding floodplain fields; and the Hohokam area had the largest canal system in pre-Hispanic North America. The cases also vary in their historical trajectories: at Zuni, population and resource use remained comparatively stable over centuries, extending into the historic period; in the Mimbres and Hohokam areas, there were major demographic and environmental transformations. Comparisons across these cases thus allow an understanding of factors that promote vulnerability and influence resilience in specific contexts.

ContributorsNelson, Margaret (Author) / Kintigh, Keith (Author) / Abbott, David (Author) / Anderies, John (Author) / College of Liberal Arts and Sciences (Contributor)
Created2010
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The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to

The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012–2014 HSPDP coring campaign.

ContributorsCohen, A. (Author) / Campisano, Christopher (Author) / Arrowsmith, Ramon (Author) / Asrat, A. (Author) / Behrensmeyer, A. K. (Author) / Deino, A. (Author) / Feibel, C. (Author) / Hill, A. (Author) / Johnson, R. (Author) / Kingston, J. (Author) / Lamb, H. (Author) / Lowenstein, T. (Author) / Noren, A. (Author) / Olago, D. (Author) / Owen, R. B. (Author) / Potts, R. (Author) / Reed, Kaye (Author) / Renaut, R. (Author) / Schabitz, F. (Author) / Tiercelin, J.-J. (Author) / Trauth, M. H. (Author) / Wynn, J. (Author) / Ivory, S. (Author) / Brady, K. (Author) / O'Grady, R. (Author) / Rodysill, J. (Author) / Githiri, J. (Author) / Russell, J. (Author, Author) / Foerster, V. (Author) / Dommain, R. (Author) / Rucina, S. (Author) / Deocampo, D. (Author) / Billingsley, A. (Author) / Beck, C. (Author) / Dorenbeck, G. (Author) / Dullo, L. (Author) / Feary, David (Author) / Garello, Dominique (Author) / Gromig, R. (Author) / Johnson, T. (Author) / Junginger, A. (Author) / Karanja, M. (Author) / Kimburi, E. (Author) / Mbuthia, A. (Author) / McCartney, T. (Author) / McNulty, E. (Author) / Muiruri, V. (Author) / Nambiro, E. (Author) / Negash, E. W. (Author) / Njagi, D. (Author) / Wilson, J. N. (Author) / Rabideaux, N. (Author) / Raub, T. (Author) / Sier, M. J. (Author) / Smith, P. (Author) / Urban, J. (Author) / Warren, M. (Author) / Yadeta, M. (Author) / Yost, C. (Author) / Zinaye, B. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-02-19
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The evolution of cooperation is a fundamental problem in biology, especially for non-relatives, where indirect fitness benefits cannot counter within-group inequalities. Multilevel selection models show how cooperation can evolve if it generates a group-level advantage, even when cooperators are disadvantaged within their group. This allows the possibility of group selection,

The evolution of cooperation is a fundamental problem in biology, especially for non-relatives, where indirect fitness benefits cannot counter within-group inequalities. Multilevel selection models show how cooperation can evolve if it generates a group-level advantage, even when cooperators are disadvantaged within their group. This allows the possibility of group selection, but few examples have been described in nature. Here we show that group selection can explain the evolution of cooperative nest founding in the harvester ant Pogonomyrmex californicus. Through most of this species’ range, colonies are founded by single queens, but in some populations nests are instead founded by cooperative groups of unrelated queens. In mixed groups of cooperative and single-founding queens, we found that aggressive individuals had a survival advantage within their nest, but foundress groups with such non-cooperators died out more often than those with only cooperative members. An agent-based model shows that the between-group advantage of the cooperative phenotype drives it to fixation, despite its within-group disadvantage, but only when population density is high enough to make between-group competition intense. Field data show higher nest density in a population where cooperative founding is common, consistent with greater density driving the evolution of cooperative foundation through group selection.

ContributorsShaffer, Zachary (Author) / Sasaki, Takao (Author) / Haney, Brian (Author) / Janssen, Marco (Author) / Pratt, Stephen (Author) / Fewell, Jennifer (Author) / College of Liberal Arts and Sciences (Contributor)
Created2016-07-28
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Prospective memory is defined as the process of remembering to do something at a particular point in the future after first forming a conscious intention. There are three types of prospective memory intentions; event-based, time-based and activity-based intentions. Research has suggested that activity-based is one of the dominant prospective memory

Prospective memory is defined as the process of remembering to do something at a particular point in the future after first forming a conscious intention. There are three types of prospective memory intentions; event-based, time-based and activity-based intentions. Research has suggested that activity-based is one of the dominant prospective memory failures that people self-report yet there is little research on this area of prospective memory. The current study focuses on how activity-based PM is influenced by the association between the match of internal context and intended action. According to previous research, similar context between intention formation and retrieval has been shown to facilitate prospective memory, which increases the execution of intentions. Based on literature, we hypothesized that there would be higher intention completion when the internal context matches the intended action to be completed in the future. Results showed that internal context affected activity-based intention completion significantly. However the interaction between internal context and the intended action did not significantly affect intention completion. Although we did not get the hypothesized interaction, the means do cross over showing the interaction pattern is there. We decided to treat this as a pilot study and replicate it with a well-powered experiment consisting of 560 valid participants.
ContributorsEdrington, Alexis Adele (Author) / Brewer, Gene (Thesis director) / Presson, Clark (Committee member) / McClure, Samuel (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2015-12
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"Gastrodiplomacy: Opening Minds by Filling Stomachs" explores the role of food as an instrument of cross-cultural exchange and understanding, in three parts: why food is an ideal medium of communication, how food exchange can be an effective catalyst of conflict resolution, and a study that highlights the relationship between ethnic

"Gastrodiplomacy: Opening Minds by Filling Stomachs" explores the role of food as an instrument of cross-cultural exchange and understanding, in three parts: why food is an ideal medium of communication, how food exchange can be an effective catalyst of conflict resolution, and a study that highlights the relationship between ethnic food consumption and positive or negative stereotyping of racial and ethnic groups. The study revealed that those who ate food that lies beyond their culture's traditional culinary boundaries fairly often were more likely to have a higher opinion of different racial and ethnic groups; those who rarely strayed beyond those boundaries were more likely to negatively stereotype different cultures. "Gastrodiplomacy" works its way through the foods of the world, and how innately geography, food, and politics are connected, whether it's through French discrimination against kebabs \u2014 a traditionally Middle Eastern food \u2014 or through the use of the dolma to help settle long-standing disputes between the warring countries of Armenia and Azerbaijan.
Created2015-05