Punish and Voice: Punishment Enhances Cooperation when Combined with Norm-Signalling

Material punishment has been suggested to play a key role in sustaining human cooperation. Experimental findings, however, show that inflicting mere material costs does not always increase cooperation and may even have detrimental effects. Indeed, ethnographic evidence suggests that the most typical punishing strategies in human ecologies (e.g., gossip, derision, blame and criticism) naturally combine normative information with material punishment. Using laboratory experiments with humans, we show that the interaction of norm communication and material punishment leads to higher and more stable cooperation at a lower cost for the group than when used separately. In this work, we argue and provide experimental evidence that successful human cooperation is the outcome of the interaction between instrumental decision-making and the norm psychology humans are provided with. Norm psychology is a cognitive machinery to detect and reason upon norms that is characterized by a salience mechanism devoted to track how much a norm is prominent within a group. We test our hypothesis both in the laboratory and with an agent-based model. The agent-based model incorporates fundamental aspects of norm psychology absent from previous work. The combination of these methods allows us to provide an explanation for the proximate mechanisms behind the observed cooperative behaviour. The consistency between the two sources of data supports our hypothesis that cooperation is a product of norm psychology solicited by norm-signalling and coercive devices.     

The Impact of Human Activities on Biological Evolution: A Topic of Consideration for Evolution Educators

There is a definitive need, at all science education levels, to strongly emphasize the central anthropogenic role humans now play in current evolutionary processes and biosphere impact. This article presents a brief overview of recent human activities; broad examples of the impact of human activities on biological evolution; a general overview and specific examples of incorporating human activities into evolution education; and further online anthropogenic resources that can be incorporated into educational settings.     

The Role of Off-line Communication in Human Evolution

The existence of embodied communication in humans places them among other living systems and helps to differentiate sign patterns that are common to all bioforms from those that are peculiarly human. Despite the fact that the biological roots of communication have been proven, the understanding of human forms of discourse is still far from being clarified. The main question remains: when and why did humans acquire the ability to exchange messages via speech? My thesis is that it became possible only after humans made a shift from on-line to off-line interaction and learned to communicate in the interpersonal mode via externalized analog codes that constitute the various forms of human culture.     

Design of humanized antibodies: from anti-Tac to Zenapax

Since the introduction of hybridoma technology, monoclonal antibodies have become one of the most important tools in the biosciences, finding diverse applications including their use in the therapy of human disease. Initial attempts to use monoclonal antibodies as therapeutics were hampered, however, by the potent immunogenicity of mouse (and other rodent) antibodies in humans. Humanization technology has made it possible to remove the immunogenicity associated with the use of rodent antibodies, or at least to reduce it to an acceptable level for clinical use in humans, thus facilitating the application of monoclonal antibodies to the treatment of human disease. To date, nine humanized monoclonal antibodies have been approved for use as human therapeutics in the United States. In this paper, we describe procedures for antibody humanization with an emphasis on strategies for designing humanized antibodies with the aid of computer-guided modeling of antibody variable domains, using as an example the humanized anti-CD25 monoclonal antibody, Zenapax.     

Thinking at the global scale

The noosphere concept was originally proposed as a sphere of mind or thought that has emerged from the biosphere over the course of human evolution. Two versions of the noosphere concept were developed in the 20th century and they differed with respect to whether the noosphere was to be considered separate from the biosphere or a new form of the biosphere. Both versions shared an assumption that collective human thought based on a scientific epistemology would achieve a benevolent relationship with the biosphere. Research in global ecology continues to reveal the growing influence of humanity on the biota and on the global biogeochemical cycles, but recent history has not confirmed humanity's ability to self‐regulate. Nevertheless, the noosphere concept remains useful because it acknowledges the uniquely subjective aspect of human brain functioning and the propensity for humans to share ideas and work collaboratively. Both of these features will be needed to develop a structured coupling of humanity and the biosphere that preserves the biophysical processes sustaining the ecosphere.     

Are Existing Global Scenarios Consistent with Ecological Feedbacks?

Scenarios can help planners and decision makers to think through uncertainties about the future and make decisions that are robust to a variety of possible outcomes. To develop useful scenarios we need to understand the main processes of relevance to the system of interest. Ecological processes, and the feedbacks that they can create between human actions and human well-being, are thought to be important for human societies. Current uncertainties over the long-term resilience of ecosystems and the substitutability of ecosystem goods and services can be translated into three alternative realities: ecosystems may be relatively brittle, relatively resilient, or largely irrelevant. Although these extremes are only rough characterizations of reality, they help us to focus our thinking about the possible outcomes of interactions between humans and the rest of the biosphere. Existing global scenarios can be categorized into a small number of families based on shared themes and assumptions about the future. Considering the internal consistency of four of the main scenario families in relation to the three alternative ecological realities suggests that all existing scenarios make strong, implicit assumptions about the resilience of ecosystems. After a detailed discussion of individual examples, we present a synthesis of the incorporation of ecology in existing scenarios. All current scenarios are inconsistent with at least one possible property of ecosystems and their likely interaction with society. The interrelationships between ecological reality, human views of ecosystems, and social responses to actual and perceived ecological change are complex. For the Millennium Ecosystem Assessment and future scenario exercises, we recommend that essential ecological assumptions should be made explicit to ensure that the details of each scenario are consistent with both the perceived and the actual degree of resilience of ecosystems.     

Is the language of intentional psychology an efficient tool for evolutionists?

The language of intentional psychology is commonly used as a means of addressing issues concerning selection. This habit is generally considered an efficient shorthand, but oft-reported misunderstandings leave room for doubt. I stress the general point that efficiency of a mode of expression is an empirical matter, deserving the same treatment, theoretically and methodologically, as other such matters. Mistaken assumptions regarding the relevant cognitive capacities may make for inefficient communication, and discourse about human evolution is a plausible case in point.     

Simulating the Real Origins of Communication

How communication systems emerge is a topic of relevance to several academic disciplines. Numerous existing models, both mathematical and computational, study this emergence. However, with few exceptions, these models all build some form of communication into their initial specification. Consequently, what these models study is how communication systems transition from one form to another, and not how communication itself emerges in the first place. Here we present a new computational model of the emergence of communication which, unlike previous models, does not pre-specify the existence of communication. We conduct two experiments using this model, in order to derive general statements about how communication systems emerge. The two main routes to communication that we identify correspond with findings from the empirical literature on the evolution of animal signals. We use this finding to explain when and why we should expect communication to emerge in nature. We also compare our model to experimental research on the origins of human communication systems, and hence show that humans are an important exception to the general trends we observe. We argue that this is because humans, and probably only humans, are able to ‘signal signalhood’, i.e. to express communicative intentions.     

Worlds within worlds: evolution of the vertebrate gut microbiota

In this Analysis we use published 16S ribosomal RNA gene sequences to compare the bacterial assemblages that are associated with humans and other mammals, metazoa and free-living microbial communities that span a range of environments. The composition of the vertebrate gut microbiota is influenced by diet, host morphology and phylogeny, and in this respect the human gut bacterial community is typical of an omnivorous primate. However, the vertebrate gut microbiota is different from free-living communities that are not associated with animal body habitats. We propose that the recently initiated international Human Microbiome Project should strive to include a broad representation of humans, as well as other mammalian and environmental samples, as comparative analyses of microbiotas and their microbiomes are a powerful way to explore the evolutionary history of the biosphere.     

Nucleotide sequence of the 3' nuclease-sensitive region of the human phosphoglycerate kinase 1 (PGK1) gene.

Many genes are known to have nuclease-sensitive sites and/or control sequences in their 3' flanking regions, but for very few genes has this region been sequenced. Previously, we mapped specific, gene activity-dependent DNAase I- and MspI-sensitive sites at the 3' end of the human X-linked housekeeping gene phosphoglycerate kinase (PGK1). Sequence information presented here shows that the 3' nuclease-sensitive site maps precisely to an Alu sequence and near a "BKM" repeat. This is the first report of an Alu sequence that has alternative chromatin configurations depending on gene activity.     

CO2 sensing in fungi and beyond

Carbon dioxide is not only an important gaseous molecule for maintenance of the biosphere homeostasis, but is also a crucial signalling cue in living cells. Fungal pathogens, including Candida albicans and Cryptococcus neoformans, must adapt to dramatic changes in CO2 levels during colonization and subsequent infection of their human host. Recent reports provide insight into how pathogenic fungi sense environmental CO2 and the role of carbonic anhydrase and fungal adenylyl cyclase in CO2 sensing.     

THE EVOLUTION OF INDIVIDUAL VARIATION IN COMMUNICATION STRATEGIES

Communication is a process in which senders provide information via signals and receivers respond accordingly. This process relies on two coevolving conventions: a “sender code” that determines what kind of signal is to be sent given the sender's state; and a “receiver code” that determines the appropriate responses to different signal types. By means of a simple but generic model, we show that polymorphic sender and receiver strategies emerge naturally during the evolution of communication, and that the number of alternative strategies observed at equilibrium depends on the potential for error in signal production. Our model suggests that alternative communication strategies will evolve whenever senders possess imperfect information about their own quality or state, signals are costly, and genetic mechanisms allow for a correlation between sender and receiver behavior. These findings provide an explanation for recent reports of individual differences in communication strategies, and suggest that the amount of individual variation that can be expected in communication systems depends on the type of information being conveyed. Our model also suggests a link between communication and the evolution of animal personalities, which is that individual differences in the production and interpretation of signals can result in consistent differences in behavior.     

Animals in flow – towards the scientific study of intrinsic reward in animals

The concept of flow, a state of complete absorption in an intrinsically rewarding activity, has played a pivotal role in advancing notions of human well-being beyond minimising suffering towards promoting flourishing and thriving. While flow has played a fundamental role in human positive psychology, it has not yet been explored in non-human animals, leaving an enormous void in our understanding of intrinsic motivation in animals. As ethology and related fields keep progressing in uncovering complex cognitive and affective capacities of non-human animals, we propose the time is ripe to translate the concept of flow to animals. We start by embedding flow in the topic of intrinsic motivation and describe its impact on positive human psychology and potentially positive animal welfare. We then disambiguate flow from related concepts discussed in the animal literature. Next, we derive experimental approaches in animals from the canonical characteristics of flow in humans and provide guidelines for both inducing and assessing flow by focusing on two characteristics that do not necessarily depend on self-report, namely resistance to distraction and time distortion. Not all aspects of the human flow experience are (yet) translatable, but those that are may improve quality of life in captive non-human animals.     

Natural IgM antibodies are involved in the activation of complement by hypoxic human tubular cells

Ischemia-reperfusion injury (IRI) has a major impact on graft survival after transplantation. Renal proximal tubular epithelial cells (PTEC) located at the corticomedullary zone are relatively susceptible to IRI and have been identified as one of the main targets of complement activation. Studies in mice have shown an important role for the alternative pathway of complement activation in renal IRI. However, it is unclear whether experimental data obtained in mice can be extrapolated to humans. Therefore, we developed an in vitro model to induce hypoxia-reoxygenation in human and mouse PTEC and studied the role of the different pathways of complement activation. Exposure of human PTEC to hypoxia followed by reoxygenation in human serum resulted in extensive complement activation. Inhibition studies using different complement inhibitors revealed no involvement of the alternative or lectin pathway of complement activation by hypoxic human PTEC. In contrast, complement activation by hypoxic murine PTEC was shown to be exclusively dependent on the alternative pathway. Hypoxic human PTEC induced classic pathway activation, supported by studies in C1q-depleted serum and the use of blocking antibodies to C1q. The activation of the classic pathway was mediated by IgM through interaction with modified phosphomonoesters exposed on hypoxic PTEC. Studies with different human sera showed a strong correlation between IgM binding to hypoxic human PTEC and the degree of complement activation. These results demonstrate important species-specific differences in complement activation by hypoxic PTEC and provide clues for directed complement inhibition strategies in the treatment and prevention of IRI in the human kidney.     

Tethering KSRP, a decay-promoting AU-rich element-binding protein, to mRNAs elicits mRNA decay

Inherently unstable mRNAs contain AU-rich elements (AREs) in their 3' untranslated regions that act as mRNA stability determinants by interacting with ARE-binding proteins (ARE-BPs). We have destabilized two mRNAs by fusing sequence-specific RNA-binding proteins to KSRP, a decay-promoting ARE-BP, in a tethering assay. These results support a model that KSRP recruits mRNA decay machinery/factors to elicit decay. The ability of tethered KSRP to elicit mRNA decay depends on functions of known mRNA decay enzymes. By targeting the Rev response element of human immunodeficiency virus type 1 by using Rev-KSRP fusion protein, we degraded viral mRNA, resulting in a dramatic reduction of viral replication. These results provide a foundation for the development of novel therapeutic strategies to inhibit specific gene expression in patients with acquired or hereditary diseases.