Hierarchies in Evolutionary Biology and Quantum Physics (original) (raw)

Hierarchy Theory as the Formal Basis of Evolutionary Theory

From a hierarchical perspective, cladistic theory is firmly rooted in developmental and evolutionary biology. It is here argued that: (1) The biological basis of homology is developmental constraint. Homologies are relationships of constraint inherited by parts of organisms. (2) A character’s coding expresses a set of assumptions about the process by which it has evolved. The ordering and weights associated with states of a character can never be independent of an evolutionary model. (3) Cladogram and tree express different kinds of evolutionary relationships. A cladogram is a hierarchy of types, where a type is the totality of constraints (homologies) inherited by a species. Types are not groups of species, but rather relationships of species. A family tree consists of monophyletic groups of ancestral and descendant species.

Philosophical foundations for the hierarchy of life

Biology & Philosophy, 2010

We review Evolution and the Levels of Selection by Samir Okasha. This important book provides a cohesive philosophical framework for understanding levels-of-selections problems in biology. Concerning evolutionary transitions, Okasha proposes that three stages characterize the shift from a lower level of selection to a higher one. We discuss the application of Okasha's three-stage concept to the evolutionary transition from unicellularity to multicellularity in the volvocine green algae. Okasha's concepts are a provocative step towards a more general understanding of the major evolutionary transitions; however, the application of certain ideas to the volvocine model system is not straightforward.

Quantum mechanical formalism for biological evolution

arXiv (Cornell University), 2010

We study the evolution of sexual and asexual populations in general fitness landscapes. We find deep relations between the mathematics of biological evolution and the formalism of quantum mechanics. We give the general structure of the evolution of populations which is in general an off-equilibrium process that can be expressed by path integrals over phylogenies. These phylogenies are sums of linear lineages for asexual populations. For sexual populations instead, each lineage is a tree of branching ratio two and the path integral describing the evolving population is given by a sum over these trees. Finally, we show that the Bose-Einstein and the Fermi-Dirac distributions describe the stationary state of biological populations in simple cases.

Quantum mechanics formalism for biological evolution

Chaos, Solitons & Fractals, 2012

We study the evolution of sexual and asexual populations in fitness landscapes compatible with epistatic interactions. We find intriguing relations between the mathematics of biological evolution and quantum mechanics formalism. We give the general structure of the evolution of sexual and asexual populations which is in general an off-equilibrium process that can be expressed by path integrals over phylogenies. These phylogenies are the sum of linear lineages for asexual populations. For sexual populations, instead, each lineage is a tree of branching ratio two and the path integral describing the evolving population is given by a sum over these trees. Finally we show that the Bose-Einstein and the Fermi-Dirac distributions describe the stationary state of biological populations in simple cases.

Three Puzzles in Hierarchical Evolution

Integrative and Comparative Biology, 2003

SYNOPSIS. The maximum degree of hierarchical structure of organisms has risen over the history of life, notably in three transitions: the origin of the eukaryotic cell from symbiotic associations of prokaryotes; the emergence of the first multicellular individuals from clones of eukaryotic cells; and the origin of the first individuated colonies from associations of multicellular organisms. The trend is obvious in the fossil record, but documenting it using a high-resolution hierarchy scale reveals three puzzles: 1) the rate of origin of new levels accelerates, at least until the early Phanerozoic; 2) after that, the trend may slow or even stop; and 3) levels may sometimes arise out of order. The three puzzles and their implications are discussed; a possible explanation is offered for the first.

Three Puzzles in Hierarchical Evolution1

2003

SYNOPSIS. The maximum degree of hierarchical structure of organisms has risen over the history of life, notably in three transitions: the origin of the eukaryotic cell from symbiotic associations of prokaryotes; the emergence of the first multicellular individuals from clones of eukaryotic cells; and the origin of the first individuated colonies from associations of multicellular organisms. The trend is obvious in the fossil record, but documenting it using a high-resolution hierarchy scale reveals three puzzles: 1) the rate of origin of new levels accelerates, at least until the early Phanerozoic; 2) after that, the trend may slow or even stop; and 3) levels may sometimes arise out of order. The three puzzles and their implications are discussed; a possible explanation is offered for the first.

Hierarchies and the Sloshing Bucket: Toward the Unification of Evolutionary Biology

Evolution: Education and Outreach

Evolutionary biology presents a bewildering array of phenomena to scientists and students alike-ranging from molecules to species and ecosystems; and embracing 3.8 billion years of life's history on earth. Biological systems are arranged hierarchically, with smaller units forming the components of larger systems. The evolutionary hierarchy, based on replication of genetic information and reproduction, is a complex of genes/organisms/demes/species and higher taxa. The ecological hierarchy, based on patterns of matter-energy transfer, is a complex of proteins/organisms/ avatars/local ecosystems/regional ecosystems. All organisms are simultaneously parts of both hierarchical systems. Darwin's original formulation of natural selection maps smoothly onto a diagram where the two hierarchical systems are placed side-by-side. The "sloshing bucket" theory of evolution emerges from empirical cases in biological history mapped onto this dual hierarchy scheme: little phenotypically discernible evolution occurs with minor ecological disturbance; conversely, greatest concentrations of change in evolutionary history follow mass extinctions, themselves based on physical perturbations of global extent. Most evolution occurs in intermediate-level regional "turnovers," when species extinction leads to rapid evolution of new species. Hierarchy theory provides a way of integrating all fields of evolutionary biology into an easily understoodand taught-rubric.