Species interactions alter evolutionary responses to a novel environment

Studies of evolutionary responses to novel environments typically consider single species or perhaps pairs of interacting species. However, all organisms co-occur with many other species, resulting in evolutionary dynamics that might not match those predicted using single species approaches. Recent theories predict that species interactions in diverse systems can influence how component species evolve in response to environmental change. In turn, evolution might have consequences for ecosystem functioning. We used experimental communities of five bacterial species to show that species interactions have a major impact on adaptation to a novel environment in the laboratory. Species in communities diverged in their use of resources compared with the same species in monocultures and evolved to use waste products generated by other species. This generally led to a trade-off between adaptation to the abiotic and biotic components of the environment, such that species evolving in communities had lower growth rates when assayed in the absence of other species. Based on growth assays and on nuclear magnetic resonance (NMR) spectroscopy of resource use, all species evolved more in communities than they did in monocultures. The evolutionary changes had significant repercussions for the functioning of these experimental ecosystems: communities reassembled from isolates that had evolved in polyculture were more productive than those reassembled from isolates that had evolved in monoculture. Our results show that the way in which species adapt to new environments depends critically on the biotic environment of co-occurring species. Moreover, predicting how functioning of complex ecosystems will respond to an environmental change requires knowing how species interactions will evolve.     

Knowing and Being Known. Approaching Australian Indigenous Tourism Through Aboriginal and Non-Aboriginal Politics of Knowing

Based on ethnographic research conducted with Bardi and Jawi people, two Indigenous groups from the Northwestern Kimberley region of Western Australia, the aim of this paper is to approach the complexities related to Indigenous tourism in Australia through the politics of knowing and not-knowing as embodied by Indigenous tour guides and non-Indigenous tourists. It examines the notion of knowing (or not-knowing) and its usages by Indigenous and non-Indigenous people in the context of their tourist encounter. ‘Knowing’ represents an important aspect through which Aboriginal people and their non-Indigenous guests negotiate their interactions. In particular, the paper shows how Indigenous and non-Indigenous expectations from tourism lead actors to adopt divergent positions and to assert renewed claims in relation to knowledge or knowing, casting new light on issues of self-representation and empowerment in the domain of Indigenous tourism.     

A New Online Database on Chemicals in Accordance with REACH Regulation

The need for comprehensive and reliable risk management of chemicals requires appropriate information, data integration, and sharing, as suggested in Europe by Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation. REACH requires more sharing of responsibilities among authorities, chemical manufacturers, importers, and users to manage the risks that chemicals can pose to human health and the environment throughout their life cycle. This has obviously enlarged the audience of people who could be interested in gathering this information. A major bottleneck is that information sources on chemicals are frequently sparsely distributed, collected, and managed by different institutions, with different aims, resulting in several practical problems. This article describes the conceptual design and implementation of a free online access database (DESC) as an integrated information system on chemical substances in compliance with the REACH regulation. An interdisciplinary approach was applied by involving several experts from different disciplines (ecotoxicologists, chemists, information technology specialists, regulators). DESC contains relevant environmental and toxicological data (physico-chemical and ecotoxicological data, inclusion in priority lists, current classification and labeling, etc.) on more than 651 chemicals, which can be easily consulted by people with different degrees of expertise interested in knowing the risk from exposure to chemicals and their safe use.     

Blood flow subject to a single cycle of body acceleration

The present study deals with the effect of a single cycle of body accelerations on blood flow in arteries. Such body accelerations are usually caused unintentionally, for example during travel in road vehicles, aircraft or spacecraft. A mathematical model of flow in single arteries subject to a pulsating pressure gradient due to the normal heart action as well as body acceleration expressible in terms of unit functions is presented. The body acceleration is such that it builds up from zero to a maximum value at a uniform rate, remains constant at the maximum value for some time, and thereafter reduces to zero at a uniform rate. The resulting equations are solved by using the technique of Laplace transforms. Computational results are presented for the effects of body accelerations on flow variables namely flow rate, velocity of flow, acceleration and shear stress corresponding to blood flow in the human aorta.     

Human Biology and Ecology: Variation in Nature and the Nature of Variation

Human biology seeks to understand human variation and the biological, environmental, social, and historical influences on that variation. Views of the nature of both variation and environment have changed during the past 100 years. Typological approaches to nature and human diversity shifted to an evolutionary perspective during the first half of the 20th century. In the second half, widespread human biological variation was documented and interpreted in terms of adaptation to the environment. Environmental physiology and reproductive ecology continue to document environmental influences on human biological functioning, but with (1) an expanded concept of environment that acknowledges more fully the interactions among its physical, biotic, and social aspects and (2) an expanded theoretical basis, drawing on evolutionary ecology and life history theory, acknowledging tradeoffs and changing constraints and opportunities over the lifetime. Human biology gains from greater interaction with other fields, such as political ecology, but also contributes to them. [Keywords: biological anthropology, human ecology, adaptation, environmental physiology, reproductive ecology]     

The limits of adaptation: humans and the predator-prey arms race

In the history of life, species have adapted to their consumers by evolving a wide variety of defenses. By contrast, animal species harvested in the wild by humans have not adapted structurally. Nonhuman predators have high failure rates at one or more stages of an attack, indicating that victim species have spatial refuges or phenotypic defenses that permit further functional improvement. A new compilation confirms that species in the wild cannot achieve immunity from human predation with structural defenses. The only remaining options are to become undesirable or to live in or escape to places where harvesting by people is curtailed. Escalation between prey defenses and predators' weapons may be restricted under human dominance to interactions involving those low-level predators that have benefited from human overexploitation of top consumers.     

The polyelectrolyte properties of elastin.

The charge structure and ionic interactions of elastin prepared from the pig thoracic aorta by acid, alkali, or CNBr extraction have been investigated by potentiometric titration and radiotracer techniques. The number of charged groups was consistent with the amino acid composition, comparable to elastin from other sources and insensitive to the method of preparation. The enthalpies of ionization of the basic groups were comparable for those previously found for proteins but those of the acidic groups were higher. Ionic interactions were predominantly electrostatic although a strong affinity for chloride ions was noted. Changes in ionic interactions as the elastin was stretched had a similar effect to an increase in the apparent fixed charge density of the tissue. Mechanical strain altered the protonation of the elastin and the pK of the carboxyl groups. Conversely, the conformation of the elastin network varied with ionic strength and pH, being particularly sensitive to the degree of ionization of the more basic groups and with the ionic strength and anion composition of the medium. We speculate that strain induced changes in the conformation of elastin altering its reactivity towards lipids, ions or matrix macromolecules or changes in its mechanical properties resulting from changes in its ionic environment may be of physiological or pathological importance.     

Impacts of Demographic and Socioeconomic Factors on Spatio-temporal Dynamics of Panda Habitat

Demographic and socioeconomic factors of individual people and households may have significant impacts on their environment, which in turn may affect the spatio-temporal dynamics of wildlife habitat and local biodiversity. In the Wolong Nature Reserve (China) for giant panda conservation, local households live a rural lifestyle that has caused forest degradation by activities such as cutting fuelwood. Based on field data and a spatial agent-based model that integrates cross-scale data and cross-discipline models, we examine how panda habitat would respond to changes in a set of socioeconomic and demographic factors individually, and under a conservation scenario and a development scenario (setting factors to values that would benefit or degrade habitat, respectively). The model simulates each family member's life history (including needs, attitudes, and activities) and the household agents' interactions with each other and with the environment through their activities over 30 years. Our simulations show that among all the factors under consideration, providing cheaper electricity and changing the age structure through increasing marriage age or prolonging the interval between consecutive births could change habitat quantity significantly (at α = 0.05 level); and the differences in panda habitat between the two scenarios escalate over time. In addition to benefiting local policy-making, this study provides a new approach to studying human–environment interactions from the perspectives of individual needs and decisions.     

Historical Ecology on Sandoy, Faroe Islands: Palaeoenvironmental and Archaeological Perspectives

We present palaeoenvironmental, geomorphological, archaeological, and place-name data which allow a holistic assessment of the history of landscape change on Sandoy, Faroe Islands, especially in terms of the changes that occurred in response to the colonization of the island by humans. In contrast to other situations in the North Atlantic region, there is considerable continuity in the patterns and processes of landscape evolution across the initial settlement horizon. Many of the characteristic features of post-settlement North Atlantic landscapes—absence of trees, widespread blanket mires, high rates of soil erosion—were already in place when the first people arrived. Although human impact on Sandoy appears to have been light, conversely, the unusual environment forced major alterations of the subsistence economy imported by the colonists. Settlement-era archaeological records suggest that, from the start, patterns of resource use differed substantially from the regional norm, and these differences became amplified over time as the Faroese economy created a locally sustainable cultural landscape.     

Alien arthropod predators and parasitoids: interactions with the environment

Many species of entomophagous arthropods have been introduced either intentionally (through the practice of biological control) or unintentionally to new regions. We examine interactions of these aliens with their new environments in the context of rapid global change linked to human activity. We consider effects of such interactions on establishment and spread of the alien species and effects on indigenous biota and ecosystems. Major elements of global change that affect alien-environment interactions include landscape modifications by humans (e.g., cultivation, habitat loss and fragmentation) and increases in atmospheric CO₂ and other gases resulting in climate change and other effects (e.g., changes in food quality for herbivores that affect higher trophic levels as well). Alien arthropod predators can alter landscapes for their benefit, to the detriment of indigenous species. A brief review also of blood-feeding alien arthropods makes clear that interactions with the environment critically influence invasions of zoophagous arthropods in general.     

Determination,a l'equilibre,des constantes d'association de ligands radioactifs ou non radioactifs par une methode non graphique

The present work deals with the determination of association constants at equilibrium by a non-graphical method in binding systems containing one specific receptor. Equations have been derived from that originally described by Lea (Biochim. Biophys. Acta, 322, 68–74), the terms of which are obtained from the data of simple displacement curves of a bound radioactive ligand by unlabelled competitors identical or different in nature. By knowing the function relating the variations of the bound ligand (B) to the affinity constant (K_i) and the quantity (M_i) of competitor for a given system, it is possible to calculate any of these parameters when the two others are measured. Thus, it becomes easy to compare the relative affinities of differents receptors for the same ligand or that of one receptor for various labelled or unlabelled ligands. Furthermore, theoretical displacement curves can be drawn and compared to experimental data, when only knowing the affinity constant of a specific binding system in given conditions. These modes of calculation have been tested in a study of interactions between various steroids and a fraction of human serum proteins precipitated by ammonium sulfate (30–45%) and containing the sex hormone-binding globulin. Association constants thus obtained agree well with those reported in the literature and determined by graphical procedures.     

Human-specific amino acid changes found in 103 protein-coding genes

We humans have many characteristics that are different from those of the great apes. These human-specific characters must have arisen through mutations accumulated in the genome of our direct ancestor after the divergence of the last common ancestor with chimpanzee. Gene trees of human and great apes are necessary for extracting these human-specific genetic changes. We conducted a systematic analysis of 103 protein-coding genes for human, chimpanzee, gorilla, and orangutan. Nucleotide sequences for 18 genes were newly determined for this study, and those for the remaining genes were retrieved from the DDBJ/EMBL/GenBank database. The total number of amino acid changes in the human lineage was 147 for 26,199 codons (0.56%). The total number of amino acid changes in the human genome was, thus, estimated to be about 80,000. We applied the acceleration index test and Fisher's synonymous/nonsynonymous exact test for each gene tree to detect any human-specific enhancement of amino acid changes compared with ape branches. Six and two genes were shown to have significantly higher nonsynonymous changes at the human lineage from the acceleration index and exact tests, respectively. We also compared the distribution of the differences of the nonsynonymous substitutions on the human lineage and those on the great ape lineage. Two genes were more conserved in the ape lineage, whereas one gene was more conserved in the human lineage. These results suggest that a small proportion of protein-coding genes started to evolve differently in the human lineage after it diverged from the ape lineage.     

On the terms used to refer to ‘natural’ forests: a response to Veen et al.

The importance of harmonizing the group of terms used to indicate ‘natural’ forests is reported in several studies. In a recent paper the term virgin forest is proposed as a unifying concept for forests which are not influenced by man in their development. In response to that paper my aim is to clarify the terms virgin and old-growth. My response focuses on two points: the term virgin forest is generally used to indicate forests that have not been influenced by people even in the distant past, therefore something different from what described by the authors; the definition drawn up for the proposed term substantially overlaps with the definition of old-growth forest resulting from a long history of studies on this theme. I think that the overlap between the two analyzed terms can ultimately only increase the existing confusion on this group of forest terms.     

Validation of a full body finite element model (THUMS) for running-type impacts to the lower extremity

The purpose of this study was to determine whether modifying an existing, highly biofidelic full body finite element model [total human model for safety (THUMS)] would produce valid amplitude and temporal shock wave characteristics as it travels proximally through the lower extremity. Modifying an existing model may be more feasible than developing a new model, in terms of cost, labour and expertise. The THUMS shoe was modified to more closely simulate the material properties of a heel pad. Relative errors in force and acceleration data from experimental human pendulum impacts and simulated THUMS impacts were 22% and 54%, respectively, across the time history studied. The THUMS peak acceleration was attenuated by 57.5% and took 19.7 ms to travel proximally along the lower extremity. Although refinements may be necessary to improve force and acceleration timing, the modified THUMS represented, to a certain extent, shock wave propagation and attenuation demonstrated by living humans under controlled impact conditions.     

Long-term land-cover changes in the Belgian Ardennes (1775–1929): model-based reconstruction vs. historical maps

Understanding long‐term human‐environment interactions requires historical reconstruction of past land‐cover changes. The objective of this study is to reconstruct past land‐use and land‐cover changes in a rural municipality of the Belgian Ardennes over the last 250 years. Two approaches were compared. The first approach produced backward projections based on a mechanistic model which computes the demand for different land uses under the assumption of an equilibrium between the production and consumption of resources. The second approach involved using a series of historical maps to extract directly land‐use areas. A stochastic Markov chain model was also used to project backward missing land‐cover data in the time series. The consistency between the results obtained with the different approaches suggests that land‐use area can be successfully reconstructed on the basis of the mechanistic model, under conditions of a subsistence farming system and a closed economy. Land‐use/cover changes in the Belgian Ardennes from 1775 to 1929 were more driven by the interventionist measures of the Belgian government and by technological progress than by the ‘pressure’ of the growing population and livestock. Thanks to agricultural intensification, a decrease in land under human use was supporting increasing human and livestock populations from 1846 to 1880. Reforestation has accelerated since the mid‐19th century. This case study illustrates the highly dynamic and non‐linear character of land‐use change trajectories over long time periods and their strong interactions with the history of societies.     

Introduction: categorization, cleverness and consciousness

Various recurring themes in the history of the subject are reviewed. In the context of adaptation to a complex environment, one precondition for survival must be a capacity for object identity, which may be the most basic form of categorization. Evidence will be presented that suggests that the capacity is not learned. In considering learned associations among categorized items, a distinction is made between reflexive and reflective processes: that is between those associations in which a cue or signal provides an unambiguous route to the response, no matter how complex that route may be, in contrast to those in which learned information must be ordered and reordered 'in thought'. An example of one experimental approach to the latter is provided. Finally, the problem of conscious awareness is considered in terms of stored categorical knowledge and associations, on the one hand, and a system that monitors them, on the other. Neurological evidence of disconnections between these different levels is reviewed.     

The memory of water: Archaeobotanical evidence of wetland plants from Modena (Emilia-Romagna,northern Italy) and palaeoecological remarks

Modena, founded by the Romans (183 BC), has always been conditioned by water in all its urban history. In the city, numerous archaeobotanical investigations have been carried out in order to reconstruct the natural landscape and human–environment interactions over time. During these investigations, four archaeological sites (two Roman and two medieval) have revealed deposits with a marked character of palaeobiocoenosis, largely resulting from the natural environment surrounding the sites, due to natural “seed rain”. These deposits are characterized by widespread evidence of plants related to water, constituting a valuable archive to investigate habitats which currently have become very rare and threatened, if they have not completely disappeared. The present paper aims to reveal the peculiarities of the Roman/medieval archaeocarpological floristic lists (through a comparison with the flora over the last two centuries in the area of Modena) and highlight the possible causes explaining the presence or the demise of several taxa, considering also the palaeoecological reconstruction of the environment in which they have been found.     

Breaking Through Disciplinary Barriers: Human–Wildlife Interactions and Multispecies Ethnography

One of the main challenges when integrating biological and social perspectives in primatology is overcoming interdisciplinary barriers. Unfamiliarity with subject-specific theory and language, distinct disciplinary-bound approaches to research, and academic boundaries aimed at “preserving the integrity” of subject disciplines can hinder developments in interdisciplinary research. With growing interest in how humans and other primates share landscapes, and recognition of the importance of combining biological and social information to do this effectively, the disparate use of terminology is becoming more evident. To tackle this problem, we dissect the meaning of what the biological sciences term studies in “human–wildlife conflict” or more recently “human–wildlife interactions” and compare it to what anthropology terms “multispecies ethnography.” In the biological sciences, human–wildlife interactions are the actions resulting from people and wild animals sharing landscapes and resources, with outcomes ranging from being beneficial or harmful to one or both species. In the social sciences, human–nonhuman relationships have been explored on a philosophical, analytical, and empirical level. Building on previous work, we advocate viewing landscapes through an interdisciplinary “multispecies lens” in which humans are observed as one of multiple organisms that interact with other species to shape and create environments. To illustrate these interconnections we use the case study of coexistence between people of the Nalu ethnic group and Critically Endangered western chimpanzees (Pan troglodytes verus) at Cantanhez National Park in Guinea-Bissau, to demonstrate how biological and social research approaches can be complementary and can inform conservation initiatives at the human–primate interface. Finally, we discuss how combining perspectives from ethnoprimatology with those from multispecies ethnography can advance the study of ethnoprimatology to aid productive discourse and enhance future interdisciplinary research.     

pH-dependent absorption in the B and Q bands of oxyhemoglobin and chemically modified oxyhemoglobin (BME) at low Cl- concentrations.

We have measured the optical absorbance in the maxima of the Q and B bands for oxyhemoglobin and oxyhemoglobin (BME) in dependence on the pH value of the solution in the region between pH 4.4 and pH 10. From the absorbance data optical titration curves are derived for both bands. These yield for oxyhemoglobin pK values 4.3, 5.3, 6.8, 7.8, and 9.0, whereas for oxyhemoglobin (BME) only one pK value at 4.3 is observed. These data are in good agreement to those derived recently from resonance Raman spectroscopy. The changes of the oscillator strengths in the Q bands are interpreted in terms of Gouterman's four-orbital model to arise from A1g-distortions of the heme group, resulting from changes of the heme-apoprotein interactions due to protonation processes of amino acid-side groups in the beta-chains. The difference between the sets of pK values in oxyhemoglobin and oxyhemoglobin BME is explained from the fact that the bifunctional reagent BME blocks important pathways of heme-apoprotein interactions. The fact that in any case increase of the Q band absorbance is accompanied by a corresponding increase in the B band absorbance leads us to the conclusion that the electronic structure of the B bands has to be described in terms of a six-orbital model, taking into account configurational interaction with the L and N bands.     

Constraints and release at different scales – The role of adaptation in biological invasions

Attempts to find a consensus on traits promoting the invasiveness of exotic species have agreed on the idiosyncrasy of successful invasions. Despite considerable efforts to integrate aspects of context-dependency into theories of invasions, none of them has provided an evolutionary perspective taking consistently into account the direction of environmental changes in terms of ‘constraint’ vs. ‘release’. Applying the filter theory of species sorting, I consider different filters at different scales explaining evolutionary changes during invasions. Within this hierarchical approach, the focus is on the factorial filters climate, abiotic environment and biotic environment, distinguishing trophic interactions and plant-plant interactions. This review summarizes the evidence of adaptive shifts from native to exotic ranges, thereby differentiating the direction of shifts with regard to either constrained or released situations. Following this systematic approach, the present paper identifies further trade-offs within hierarchical levels complementing already existing hypotheses such as those for biotic interactions. In particular, the role of climatic changes should more explicitly be linked with evolutionary responses during invasions. Studying exotic species successfully invading several regions with different environmental conditions will be a promising starting point to enlarge the understanding of context-dependency of invasions.