Telmo Pievani

The sixth mass extinction: Anthropocene and the human impact on biodiversity

Mass extinctions are a major pattern in macroevolution. Because of their frequency, quickness and global effects, they shaped the global biodiversity several times during the geological ages. As an integrative factor with respect to microevolutionary Neo-Darwinian processes, mass extinctions are probably due to a set of different possible causes (basaltic super-eruptions, impacts of asteroids, global climate changes, continent drifts, and so on). An analogy has been proposed. If we compare the rates and amounts of extinction during those singular evolutionary events with the range of species losses over the past few centuries and millennia in human times, we see a similar trend. Then, according to a group of authoritative evolutionists like Edward O. Wilson and Niles Eldredge, we have evidence that humans are now causing the so called “Sixth Mass Extinction”. “Anthropocene” also means that Homo sapiens has become a dominant evolutionary force. Through a mix of different significantly impacting activities (i.e., fragmentation of habitats, overpopulation, chemical pollution, invasive species, over-exploitation of resources in hunting and fishing), we have produced the conditions for a serious extinction crisis. According to Nature (March 2011), the sixth mass extinction is under way: “we find that Earth could reach that extreme within just a few centuries if current threats to many species are not alleviated” (Barnosky et al. 2011). We discuss here a recent model for mass extinctions (the “Perfect Storm Model”), based on the idea that these macroevolutionary patterns could be produced by a mix of three main simultaneous causes and conditions.

Born to Cooperate? Altruism as Exaptation and the Evolution of Human Sociality

In recent papers (e.g. Wilson and Wilson, 2007), it has been confirmed that the two standard solutions for the apparent paradox of the evolution of altruism and pro-social behaviours – ‘kin selection’, which leaves unsolved the question of population structure, and ‘group selection’ – can indeed be consistent with one other. The result is a possible explanation of the ambiguity between deeply entrenched attitudes to cooperation inside social groups and organized hostility among them (Bowles, 2008). Nevertheless, these models seem to undervalue the potential effects of ‘multilevel’ evolution and both notions remain strongly engaged with gene-centred interpretations of evolutionary dynamics – which lose their explanatory power when applied to group-living species that show unconditioned forms of altruism and pro-social feeling, especially when cultural evolution enters the process. In order to avoid ‘cultural discontinuity’ hypotheses at the other extreme, I emphasize the importance of ‘functional cooptation’, or ‘exaptation’ (Gould and Vrba, 1982; Gould, 2002) in arriving at a more satisfying explanation of the origins of free or reciprocal unselfishness, in group-living animals and in culture-bearing species.

Multi-level human evolution: ecological patterns in hominin phylogeny.

Evolution is a process that occurs at many different levels, from genes to ecosystems. Genetic variations and ecological pressures are hence two sides of the same coin; but due both to fragmentary evidence and to the influence of a gene-centered and gradualistic approach to evolutionary phenomena, the field of paleoanthropology has been slow to take the role of macro-evolutionary patterns (i.e. ecological and biogeographical at large scale) seriously. However, several very recent findings in paleoanthropology stress both climate instability and ecological disturbance as key factors affecting the highly branching hominin phylogeny, from the earliest hominins to the appearance of cognitively modern humans. Allopatric speciation due to geographic displacement, turnover-pulses of species, adaptive radiation, mosaic evolution of traits in several coeval species, bursts of behavioral innovation, serial dispersals out of Africa, are just some of the macro-evolutionary patterns emerging from the field. The multilevel approach to evolution proposed by paleontologist Niles Eldredge is adopted here as interpretative tool, and has yielded a larger picture of human evolution that integrates different levels of evolutionary change, from local adaptations in limited ecological niches to dispersal phenotypes able to colonize an unprecedented range of ecosystems. Changes in global climate and Earths surface most greatly affected human evolution. Precisely because it is cognitively hard for us to appreciate the long-term common destiny we share with the whole biosphere, it is particularly valuable to highlight the accumulating evidence that human evolution has been deeply affected by global ecological changes that transformed our African continent of origin.

How to Rethink Evolutionary Theory: A Plurality of Evolutionary Patterns

Nature has recently depicted the empirical advancements of the theory of evolution as a confrontation between “reformists”, that claim for an urgent rethinking of the standard neo-Darwinian approach including so far neglected factors and processes, and “conservatives” who reply “all is well” about the current evolutionary research programme based on genetic variation and natural selection. The fight is mainly around genetic reductionism, but it seems inconclusive. Reformists stress very important factors, but they are still missing a coherent proposal about the architecture of the future extended evolutionary theory. Conservative react defensively, relying just on non-essential add-ons to the old and stable neo-Darwinian core. We analyze the debate and we propose an interpretation. Evolutionary biology is a rapidly expanding field. The bone of contention is how to update and extend the central core of the Darwinian legacy. We propose here the idea that what is happening in the field today is a development of the evolutionary research programme, whose structure is composed of a set of compatible and integrated evolutionary patterns. Evolutionary biology has been extended over its history by the inclusion of more and more patterns, rather than by revision to core theory. Niles Eldredge’s “Hierarchy Theory” is an example of global structure (meta-theory) aiming at incorporating and unifying the currently observed evolutionary patterns.

The Incompleteness of Each Tradition: Toward an Ethic of Complexity (L'incompiutezza di Ogni Tradizione: Verso Un'etica Della Complessita)

Abstract This article addresses the power of human technologies to wreak destruction on a planetary scale, such as genetic manipulation and weapons of mass destruction. It proposes the need for a new ethic that would be planetary in scale. Its central aim would be to include the great historical and contemporary diversity of human cognitive and epistemological experience. An “ethic of complexity” can weave together the threads of our common heritage. Although humanitys evolutionary past has been shown to be quite diverse, recent genetic and anthropological research has shown it also to be surprisingly unified. New images and metaphors are providing humanity with a vision that transcends familiar ethnic hatreds and so-called clashes of civilizations. The new planetary culture can be a shining example of unity-in-diversity, or unitas multiplex. It will be robustly diverse, intermixed to the core, and filled with awe at the rich lineages of our common past.

Mirror neurons in the tree of life: mosaic evolution, plasticity and exaptation of sensorimotor matching responses

Considering the properties of mirror neurons (MNs) in terms of development and phylogeny, we offer a novel, unifying, and testable account of their evolution according to the available data and try to unify apparently discordant research, including the plasticity of MNs during development, their adaptive value and their phylogenetic relationships and continuity. We hypothesize that the MN system reflects a set of interrelated traits, each with an independent natural history due to unique selective pressures, and propose that there are at least three evolutionarily significant trends that gave raise to three subtypes: hand visuomotor, mouth visuomotor, and audio–vocal. Specifically, we put forward a mosaic evolution hypothesis, which posits that different types of MNs may have evolved at different rates within and among species. This evolutionary hypothesis represents an alternative to both adaptationist and associative models. Finally, the review offers a strong heuristic potential in predicting the circumstances under which specific variations and properties of MNs are expected. Such predictive value is critical to test new hypotheses about MN activity and its plastic changes, depending on the species, the neuroanatomical substrates, and the ecological niche.

Education in Evolution and Science Through Laboratory Activities

Evolution is the unifying framework for the science of biology. [...] It likewise demands an equally dominant role in biology education. [...] Simultaneously it is the most important, the most misunderstood, and most maligned concept in the syllabus—if it even appears in the syllabus (Investigating Evolutionary Biology in the Laboratory, by William F. McComas (ed.). Dubuque (Iowa): Kendall-Hunt, 2006. pp. vi + 388. s/b

Individuals and groups in evolution: Darwinian pluralism and the multilevel selection debate

41, 99).

Humans’ Place in Geophysics: Understanding the Vertigo of Deep Time

Outlined here is an updated review of the long-standing ‘kin selection vs group selection’ debate. Group selection is a highly contentious concept, scientifically and philosophically. In 2012, Dawkins’ attack against Wilson’s latest book about eusociality concentrated all the attention on group selection and its mutual exclusivity with respect to inclusive fitness theory. Both opponents seem to be wrong, facing the general consensus in the field, which favours a pluralistic approach. Historically, despite some misunderstandings in current literature, such a perspective is clearly rooted in Darwin’s writings, which suggested a plurality of levels of selection and a general view that we propose to call ‘imperfect selfishness’. Today, the mathematically updated hypothesis of group selection has little to do with earlier versions of ‘group selection’. It does not imply ontologically unmanageable notions of ‘groups’. We propose here population structure as the main criterion of compatibility between kin selection and group selection. The latter is now evidently a pattern among others within a more general ‘multilevel selection’ theory. Different explanations and patterns are not mutually exclusive. Such a Darwinian pluralism is not a piece of the past, but a path into the future. A challenge in philosophy of biology will be to figure out the logical structure of this emerging pluralistic theory of evolution in such contentious debates.

Bellarmine's Revenge? On Some Recent Trends in the Roman Catholic Church Concerning the Relation of Faith and Science

We define the phenomenon of “denialism in science” (denial of scientific evidence without any support), its multiple facets, and its influential cognitive roots. Biological evolution and geophysical evidence are preferred topics for deniers in scientific issues. The case history of peculiar denialism in Canadian conservative government is outlined and interpreted as an example of insidious manipulative strategy against the acceptance and diffusion of scientific evidences. Earth sciences and evolutionary biology share a set of counterintuitive features, which can explain the psychological success of denialism in public debates. The roots of these counterintuitive features are briefly presented. The popular appeal of pseudoscience and denialism makes it clear that receiving solid teaching of the value of scientific thought and the scientific method early in life is of fundamental importance.