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The hierarchical interplay between ecology and genealogy is a fundamental ingredient for the most compelling current explanations in evolutionary biology. Yet philosophy of biology has hardly welcomed a classic fundamental intuition by palaeontologist Niles Eldredge, i.e. the non-coincidence and interrelation between ecology and genealogy, and their interaction in a Sloshing Bucket fashion. Hierarchy Theory and the Sloshing Bucket need to be made precise, developed and updated in light of an explosion of new discoveries and fields and philosophical issues. They also suggests re-thinking concepts such as natural selection, species, and speciation that have always been part of evolutionary theory La interacción jerárquica entre ecología y genealogía es un ingrediente fundamental de las más convincentes explicaciones de la biología evolucionista en la actualidad. Sin embargo, la filosofía de la biología apenas ha acogido una intuición fundamental y clásica debida al paleontólogo Niles Eldredge, a saber: la no-coincidencia e interrelación entre la ecología y la genealogía, y su interacción a modo de cubeta rebosante. La Teoría de la Jerarquía y la de la Cubeta Rebo- sante necesitan mayor precisión, así como un ulterior desarrollo y acutalización a la luz de la explosión de nuevos descubrimientos y campos y de cuestiones filosóficas. Siguieren asimismo la necesidad de repensar conceptos tales como selección natural, especie y especiación, que han formado siempre parte de la teoría evolucionista

The concept of exapta

Considering recent data coming from different disciplines like molecular biology and palaeontology – handled as elements of an inference towards the best explanation – here we explore the hypothesis that the development of a fully articulated language favoured key cultural innovations, which in turn pushed the last population wave of Homo sapiens out of Africa about 60 to 50K ago. Human biogeography could be the keystone for the correct interpretation of the fragmentary data concerning the so-called “Paleolithic Revolution”. It is possible that the “final wave” of people out of Africa after the period of 60K, associated with the L3 haplogroup, was the bearer of the behavioural innovations which until now have been associated with the symbolic revolution. In “The Final Wave” model, the evolutionary process is continuous, but with punctuated bursts of innovations in small populations; there is a direct liaison between biological evolution and cultural evolution (with the latter grafted onto the former); a growing interdisciplinary collection of evidence is unified in a frame stressing the role of biogeography in the evolution of cognitively modern human behaviour.

Hierarchy theory (e.g. Salthe 1985, Eldredge 1986) provides a unifying approach for representing the multi-level structure of the organic world and an explanatory framework for the wide range of natural phenomena. Its birthdate can be located in the 1980s, when evolutionary biologists began exploring in detail the nature of hierarchical systems as an approach to understanding both the nature of these complex systems, and the nature of their interactions that underlie the evolutionary process. Nowadays hierarchy theory is being developed and updated in light of an explosion of new discoveries and fields, but also as a way of re-thinking and re-framing concepts, like speciation, that have been present in evolutionary theory for many decades. According to hierarchy theory, organisms are parts of at least two different kinds of systems: (1) matter-energy transfer systems, where organisms are parts of local populations that in turn are parts of local ecosystems. The economic roles played by such populations are what constitute ecological niches. Local ecosystems are parts of regional systems, a geographic mosaic of matter-energy transfer systems that together constitute the global biosphere. (2) genetically-based information systems: organisms are parts of local breeding populations that in turn are parts of each individual species. Species, through the process of evolution, are parts of historical lineages: genera, then families, orders etc. of the Linnaean Hierarchy. While evolutionary theory has legitimately focused most on genetic processes and the formation of genetic lineages, evolution does not occur in a vacuum: specifically, it is what takes place inside matter-energy transfer systems that determines, in large measure, the patterns of stability and change in genetic systems that we call “evolution”. The “sloshing bucket theory of evolution” (Eldredge 2003) is an example of how theoretical hierarchy theory applies to the real world of biological systems and their histories. The theory describes the multilevel interplay between ecological disruption, taxic extinction and consequent bursts of evolutionary diversification. The pulse, pace and scope of ecological disruptions – ranging from localized disturbances; regional, longer term disruptions; and (rarely) drastic global environmental change – have corresponding effects on dynamic matter-energy systems on different scales. Localized disruptions result in re-establishment of very similar local ecosystems, based on genetic recruitment of members of the same species still living outside the affected area; on the grandest scale, mass extinctions resulting from global environmental disruption witness the disappearance of larger-scale taxonomic entities. Over periods of millions of years (5-10 my, typically), the ecological roles played in the now-disrupted ecosystems by organisms in now-extinct groups are assumed by evolutionarily modified species that are derived from taxa that survived the extinction event. The intermediate situation – where regional ecosystems are disturbed, resulting in the extinction of many species – is perhaps of the greatest interest: the fossil record shows clearly that most speciation events (hence most evolutionary genetic change in the history of life) take place as a consequence of regional ecosystemic collapse and multiple extinctions of species across different lineages. Traditional presentations of speciation commonly depict one species at a time, and classify speciation events on a geographical basis (allopatric, peripatric, sympatric etc.). In light of hierarchy theory, both these habits are wrong, and a rethinking the process of speciation is needed to explicitly describe the interaction between (1) economic and (2) genealogical events. First, with “geographic speciation”, more than an eco-geographical event we actually mean one of the possible genealogical consequences of ecological barriers, i.e. the multiplication of genealogical entities at the level of species within instances of the evolutionary hierarchy (we use the biological concept of species, with no necessary link with the individuality thesis). As Gavrilets (2010) pointed out, a geographical taxonomy of speciation is silent about what happens in the genealogical hierarchy, for example about the kinds of genetic, morphological or behavioral “uncoordination” that yield reproductive isolation. A new taxonomy of processes of genealogical diversification (e.g., sympatric speciation, birth of varieties and subspecies, agamospecies) is possible. On the other hand, geographic barriers impact many species at once: ecological events which arguably trigger speciation are cross-phyletic. Second, a proper re-description of geographic speciation should contextualize the phenomenon properly in the scenario of ecological systems (ecosystems and, at a macroevolutionary time scale, faunas). Sometimes speciation can be adaptive (a critical assessment of its relative frequency would be necessary). But the important thing is that adaptation – usually seen from an intra-populational point of view – should as well be described in the context of ecological reassortment and reshaping of communities. We are in presence of contemporaneous processes that occur at the population-ecological time scale at different levels of the ecological hierarchy, inviting reinterpretation of the concepts of adaptation and fitness, coevolution, and niche construction. Intra-populational, inter-individual variation of ecologically relevant traits is examined as the “raw recruit” for natural selection. Transversal comparison among ecological communities brings into focus patterns in ecological processes and systems, and also processes like adaptive convergence. In this way, some epistemological problems which are usually related to adaptation disappear, and new ways of framing the issue emerge. For example, coevolution is not a separate issue, neither it is niche construction, i.e., the cross-genealogical modification of selective pressures as a consequence of the existence and activity of populations, including the interactive role of abiotic factors. It is important to remark that this re-worked speciation concepts seems to play a key role in the most updated views on hominid evolution.

Palaeontologists Stephen J. Gould and Elisabeth Vrba introduced the term “ex-aptation” (Gould, Vrba, 1982; Vrba, Gould, 1986) with the aim of improving and enlarging the scientific language available to researchers studying the evolution of any useful character, instead of calling it an “adaptation” by default, coming up to what Gould named an “extended taxonomy of fitness” (Gould, 2002). With the extension to functional co-optations from non-adaptive structures (“spandrels”), the notion of exaptation expanded and revised the neo-Darwinian concept of “pre-adaptation” (which was misleading, for Gould and Vrba, in suggesting foreordination). Exaptation is neither a “saltationist” nor an “anti-Darwinian” concept and, from 1982 to date, was adopted by many researchers in evolutionary and molecular biology, and particularly in human evolution. Exaptation was also addressed with some theoretical objections. With respect to one of these - the “non-operationality objection” - we analyze the possible operationalization of the concept in two recent meaningful studies, and identify six directions of empirical research, necessary to test “adaptive vs. exaptive” evolutionary hypotheses. We then write on a comprehensive survey (available online) of the literature, and on the basis of this we make a quantitative and qualitative evaluation of the adoption of the term among scientists who study human evolution.We discuss the epistemic conditions that may have influenced the adoption and appropriate use of exaptation, and comment on the benefits of an “extended taxonomy of fitness” in present and future studies on human evolution.

Science is culture because it helps us answer questions that go well beyond experimental results: From where do we come? and Why are we here? Genetics and palaeontology tell us that we are on a two million year journey: from when the first examples of the genus Homo, our bipedal ancestors, spread from Africa and colonized Eurasia on several occasions; from when, much later, small groups belonging to our curious and resourceful species, Homo sapiens, left Africa again and undertook the exploration of old and new worlds.

Accademia Nazionale dei Lincei, International Conference Rome, 11 February - 12 February 2009.

Since 2005 the website Pikaia (http://www.pikaia.eu) is active in Italy keeping Italian readers informed about everything new happening in the fields of evolution in Italy and abroad and suggesting news, papers, books, websites, congresses and seminars.

Many studies about organizational experiences and theories converge today in the idea that the economic factor, most competitive now in the production of value, is the de-materialization of the economical and organizational processes. Immaterial factors (like knowledge, services, information, relationships, virtual transactions, etc.) are the competitive and crucial innovations for future competition and, at the same time, the most important criteria to rethinking and understanding the future organization. If this is true, we can realize that every person in organizations, every personal history in organizations, or better the evolutionary uniqueness of every person in organizations, is the real depositary and bearer of this de-materialization.

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 humanity's 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.

This article looks at the prevalent view of time in the history of Western philosophy and science and then contrasts it with the emerging new vision of time as ontologically constructive. Throughout Western history, philosophers and scientists attempted to marginalize and anesthetize the role of time by prioritizing being over becoming. But beginning with the Darwinian revolution in biology, the West could no longer deny the constructive role of time in bringing forth new ontological orders. While the 20th century witnessed the split between the reversible time of physics and the developmental time of biology, the time has now come for this divide to be reconciled. Twenty-first century science is already revealing the constructive role of time in cosmology with the likelihood of multiple universes. In conclusion, the authors speculate that our moment in human cultural development is ripe for a complex, multidimensional, and transdisciplinary understanding of time.

The author intends to give the outlines of a possible "radical theory of emergence" in development processes (biological and cognitive). Said theory should be based on two main observations: 1) development processes are emergence phenomena starting from reticular connections that concern the integrated totality of the systems being studied (internal source of the order); 2) development processes occur within structurally coupled systems whose co-evolutional structure has characteristics of irreducible uniqueness and contingency (external source of the order). The endogenous aspect and the exogenous aspect in the production of order in complex systems are here to be understood as being complementary and simultaneous. The two observations on the exo-endogenous character of development can then be generalized into a third: the crisis of the computational paradigm is read via the crisis of adaptationalist thought, sketched by biologists like Francisco Varela, by evolutionists like Stephen J. Gould and Richard Lewontin, as well as philosophers of biology like Susan Oyama. Following the latter's Development Systems Theory (DST), two possible directions are here explored to formulate an epistemological reflection on development in an emergentist and co-evolutionist key: a) a direction that tries to trace the "ontogenetic" (i.e. relevant to individual development) origins of the structural subject/object paring, which Varela defined as "embodiment" of knowledge; b) a direction that tries to trace the "phylogenic" (i.e. relevant to the biological evolution of our species) origins of this "incarnation" of the mind.

This dissertation brings a contribution to the philosophical debate on adaptive landscapes, an influent "model" or "metaphor" in evolutionary biology. Some elements of innovation are: the distinction between native and migrant metaphor; a processual and communicational idea on what the Modern Synthesis was, and on what role a metaphor could have played in it; a view (taken by Richard Lewontin) of the disunity and theoretical structure of population genetics; the distinction between “adaptive surfaces” (mainly metaphors) and “combination spaces”, two terms normally conflated in the word “landscape”; an analysis of what bridges (including heuristics) may be cast between equations of gene frequency and the genotype space that, due to its huge dimensionality, cannot be handled by mathematics; a specified vocabulary to be used to clear the adaptive landscapes debate, accompanied by a plea in favor of a pragmatic approach - for example, the plurality of available notions of model forces us to choose one notion and see where it brings, otherwise we get stuck in confused, endless debates; an updated analytical comment of recent landscapes - Dobzhansky, Simpson, Dawkins but also the proliferation of combination spaces used in evolutionary biology to address a great variety of problems; the vision (got by Sergey Gavrilets) of a patchwork of tools finally making Mendelian population suitable model also for speciation; the exact position of holey landscapes in this patchwork, and the idea that scientists’s questions - like “how possibly” questions - matter in accessing this patchwork and in deciding “what explains” and “what describes” what in the world; the direct response to some mistakes Massimo Pigliucci made, I think, in his assessment of the adaptive landscape; an analysis of the Extended Evolutionary Synthesis project at its present stage, and some reflections on the conditions that will allow such a project to give a fair treatment and a good position to tools from the past, like the adaptive landscapes.