What is the Hierarchy Group?

The Hierarchy Research Group is an international network of research composed by highly-qualified scholars in evolutionary biology, paleontology, anthropology, genetics, ecology and philosophy of biology. The group met in Genoa (2006), Havana (2010), Salt Lake City (2011) and, more recently, in Padua (2014). The general aim of this Group is to consolidating and extending its initial advances, identifying questions in natural sciences in which Hierarchy Theory provides the most comprehensive solutions, and discovering new promising avenues for its application.

What is the Hierarchy Group website?

In such a perspective, the Hierarchy Group website is intended as a useful device to spur International scientific discussion and its goal is to promote and establish an enduring international network of Institutions and scholars devoted to the hierarchical approach to evolution. This is the first website completely dedicated to the Hierarchy Approach and emergent issues of life complexity. It is not a news-based one, but rather an organized academic scientific repository of up-to-date material and links to hierarchy theory. The main interest of this completely open website is that hierarchy theory becomes as much known as possible both among established professionals, science students, and interested people.


↘ What is the Hierarchy Group project?

This website is part of a larger pilot project entitled “The Hierarchy Group: Approaching Complex Systems in Evolutionary Biology” and funded by the Templeton Foundation (

The coordination of the research activities of the project is provided by the headquarters at the Department of Biology of the University of Padua (Italy), but the entire project is also based on a solid and essential International network of scientific institutions able to provide administrative and logistic support at any stage.

The Project Leader, Professor Niles Eldredge, is the founder of the Hierarchy Approach, and one of the world’s leading evolutionists. The Project Co-Leader, Professor Telmo Pievani, is an internationally established philosopher of biology, with demonstrated experience in group coordination and the communication of science. Professor Ian Tattersall, at the congress in Havana (2010) presented a talk about Hierarchy Theory and human evolution, titled: “Emergence in the Origin of Human Symbolic Cognition”. The other scholars involved (see “people” section of this website) are at the frontier of these researches and leading participants in the currently relevant International scientific literature. The highest levels of excellence and scientific credibility are assured by this panel of participants.

The main aim of this project is to pursue a methodology of coordinated interdisciplinary research, within an already-established theoretical core – namely the Hierarchy Theory of evolution and multilevel approach to the complexity of life –, mainly focused on the publication of peer-reviewed papers and a multi-authored book.


The multi-authored book: a hierarchical perspective on evolution

The primary goal of the Hierarchy Group’s project is the realization of a multi-authored book about the Hierarchy Approach to evolution, and its dissemination. Despite the significant impact of Hierarchy Theory on evolutionary biology, no comprehensive and up-to-date treatment of the subject has yet been published. At the two most recent meetings of the Hierarchy Group – especially at the last one held in Padua –, plans were discussed to organize in detail a thematically integrated multi-authored book which aims to synthesize advances in the hierarchy theory of evolution. The provisional book title is “Evolutionary Theory: A Hierarchical Perspective”. This publication has the potential of becoming a seminal contribution to contemporary evolutionary biology. Apparently familiar topics (e.g., speciation, extinction, adaptation, natural selection, genetic inheritance and variation, common descent, phylogeny) will be presented with a genuinely novel approach in the hierarchical framework, which incidentally has the potential to bring ecology and evolution back together, after a period of separation by outdated disciplinary fences. The same framework will allow discussion in an integrated way of the issues that are most debated, such as co-evolution, development, phenotypic plasticity, niche construction, genomic evolution, multiple channels of inheritance, and macro-evolutionary patterns and processes. Publication of the book will be both significant and timely, because it will provide a single explanatory framework for integrating the tremendous recent advances in various specialized areas of biology (from clarifying the molecular processes of development, to enlightening the framework of the entire tree of life), and will concurrently revitalize a higher education curriculum by introducing the new approach in a textbook format. In fact, the book is intended to serve also as an advanced undergraduate-graduate level textbook as well as a stand-alone, state-of-the-art publication on the subject (the first of its kind) that will be accessible to a general audience.

The multi-authored book, together with this website, will be a longer-term tool for a more general audience of educators and teachers, not only in universities but also in colleges and schools.


A series of peer reviewed papers

The core output of this project also includes a set of submissions and peer-reviewed publications that will anticipate and set the stage for the aforementioned book. In view of the personnel involved in the project (team leaders, senior researchers, core scholars, young researchers, with multiple possibilities of multi-authored articles), we plan preparation of at least six/seven peer-reviewed papers on the main issues of Hierarchy Theory (both specialized in certain fields and interdisciplinary), with particular attention to the current international debates in evolutionary biology and philosophy of biology. Tentative specific topics of the papers will include: the historical and philosophical role of a hierarchical approach in the extension and revision of the general structure of evolutionary theory; Hierarchy Theory and other multi-level approaches to evolution; convergence of ecology and genetics as a core methodology for future evolutionary researches; a revision of speciation and other major evolutionary concepts; Hierarchy Theory and human evolution: the emergence of Homo sapiens; biological evolution and cultural evolution from a hierarchical perspective; and Giovan Battista Brocchi, the first hierarchy thinker in evolutionary biological history.

↘ International meetings

One internal workshop was recently held at the Department of Biology in Padua (May 2014), at the beginning of the project activities, devoted to sharing the results of researches already carried out, to establishing, coordinate and plan the implementation of the main specific aims of the project.  Furthermore, a final International public event with presentation and discussion of the outcomes of the project will be organized in New York in March 2016. This second meeting will be an open event for the dissemination of results, the presentation of the book to the public, discussion of the subject with other experts and specialists with different viewpoints, and the launch of future researches and projects.


↘ What does the Hierarchy Group expect to find from the research?

The most significant expected findings from the research will be:

  • a shared and defined version of the Hierarchy Theory of Evolution, in all its aspects, and viewed as a unifying approach to representing the complex multi-level structure of the organic world;
  • reconstruction of the historical roots of this approach in the development of biological thought;
  • the implications of this pluralistic approach for the renewal of evolutionary studies at large;
  • its implications for the researches about complex biological systems;
  • its implications for the study of the relationships between different levels and units in evolution (microevolution and macroevolution; ecology and evolution; genealogical entities and ecologic entities);
  • its implications for the researches in human evolution and anthropology (integrating biological and cultural evolution);
  • its philosophical and methodological consequences (crisis of genetic reductionism);
  • its educational applications;
  • its impact on public debates about evolutionary issues.

↘ The future of the Hierarchical Theory of Evolution: an enduring impact?

The last few decades have witnessed considerable advances in the production of explanatory patterns in evolutionary biology. Some authors have proposed to gather all these novelties in an Extended Evolutionary Synthesis in order to update the Modern Synthesis. The approach followed in this project suggests that the appropriate way to handle this vast range of evolutionary phenomena is to frame them into a hierarchical, complex, and pluralistic view.

A major consequence of the paradigm shift in life sciences produced by the application of Hierarchy Theory to evolutionary biology was a shift in focus towards approaching complexity in living systems in new ways. It opened new avenues for empirical and theoretical research,

demanding development of novel tools and methodologies. Having formalized the theoretical foundations, the Hierarchy Group is entering a new stage of applying the Hierarchy Theory of evolution to new biological questions and phenomena beyond biology proper.

Several emerging evolutionary fields – like evolutionary developmental biology, epigenetics, phenotypic plasticity, the interplay between functional and structural factors in evolution – are demanding a revision and extension of the structure of evolutionary theory, begun decades ago with the Neutralistic approach and Punctuated Equilibria theory. The forthcoming structure of the theory of evolution appears as a scientific research programme, that is a set of integrated and plural patterns of explanation for any evolutionary phenomenon.

Hierarchy Theory, as a frame integrating ecological and genealogical levels of evolution, is a favorite candidate to be the theoretical core of this emerging pluralistic Evolutionary Research Programme for the future.

It could also have a sound effect, in public debates, questioning the successful but misleading reductionist and gene-centered rhetoric of much of contemporary evolutionary theory. Furthermore, there are multiple connections, between the ecological and evolutionary hierarchies, on the one hand, and human adaptations, most certainly including human social behavior, on the other. So, a significant development will be the application of Hierarchy Theory to human biological and cultural evolution.

Then the enduring impact of Hierarchy Approach will make a difference in scientific terms (inside the heterogeneous community of evolutionary studies), in educational terms (envisaging new curricula and syllabuses), in communicational terms (against over-simplifications of evolution), and in cultural terms, promoting new connections with non-strictly biological fields and with philosophy and humanities at large. For all these reasons, we expect that Hierarchy Theory will influence future researches.