It has long been recognized that cancer onset and progression represent a type of reversion to an ancestral quasi‐unicellular phenotype. This general concept has been refined into the atavistic model of cancer that attempts to provide a quantitative analysis and testable predictions based on genomic data. Over the past decade, support for the multicellular‐to‐unicellular reversion predicted by the atavism model has come from phylostratigraphy. Here, we propose that cancer onset and progression involve more than a one‐off multicellular‐to‐unicellular reversion, and are (...) better described as a series of reversionary transitions. We make new predictions based on the chronology of the unicellular‐eukaryote‐to‐multicellular‐eukaryote transition. We also make new predictions based on three other evolutionary transitions that occurred in our lineage: eukaryogenesis, oxidative phosphorylation and the transition to adaptive immunity. We propose several modifications to current phylostratigraphy to improve age resolution to test these predictions. Also see the video abstract here: https://youtu.be/3unEu5JYJrQ. (shrink)

There is a widespread assumption that the universe in general, and life in particular, is 'getting more complex with time'. This book brings together a wide range of experts in science, philosophy and theology and unveils their joint effort in exploring this idea. They confront essential problems behind the theory of complexity and the role of life within it: what is complexity? When does it increase, and why? Is the universe evolving towards states of ever greater complexity and diversity? If (...) so, what is the source of this universal enrichment? This book addresses those difficult questions, and offers a unique cross-disciplinary perspective on some of the most profound issues at the heart of science and philosophy. Readers will gain insights in complexity that reach deep into key areas of physics, biology, complexity science, philosophy and religion. (shrink)

In the atavistic model of cancer progression, tumor cell dedifferentiation is interpreted as a reversion to phylogenetically earlier capabilities. The more recently evolved capabilities are compromised first during cancer progression. This suggests a therapeutic strategy for targeting cancer: design challenges to cancer that can only be met by the recently evolved capabilities no longer functional in cancer cells. We describe several examples of this target‐the‐weakness strategy. Our most detailed example involves the immune system. The absence of adaptive immunity in immunosuppressed (...) tumor environments is an irreversible weakness of cancer that can be exploited by creating a challenge that only the presence of adaptive immunity can meet. This leaves tumor cells more vulnerable than healthy tissue to pathogenic attack. Such a target‐the‐weakness therapeutic strategy has broad applications, and contrasts with current therapies that target the main strength of cancer: cell proliferation. (shrink)

This book tackles the most difficult and profound open questions about life and its origins from an information-based perspective.

Astrobiologists are aware that extraterrestrial life might differ from known life, and considerable thought has been given to possible signatures associated with weird forms of life on other planets. So far, however, very little attention has been paid to the possibility that our own planet might also host communities of weird life. If life arises readily in Earth-like conditions, as many astrobiologists contend, then it may well have formed many times on Earth itself, which raises the question whether one or (...) more shadow biospheres have existed in the past or still exist today. In this paper, we discuss possible signatures of weird life and outline some simple strategies for seeking evidence of a shadow biosphere. Key Words: Weird life—Multiple origins of life—Biogenesis—Biomarkers—Extremophiles—Alternative biochemistry. Astrobiology 9, 241–249. (shrink)

: All known life requires phosphorus (P) in the form of inorganic phosphate (PO43x or Pi) and phosphate-containing organic molecules. Pi serves as the backbone of the nucleic acids that constitute genetic material and as the major repository of chemical energy for metabolism in polyphosphate bonds. Arsenic (As) lies directly below P on the periodic table and so the two elements share many chemical properties, although their chemistries are sufficiently dissimilar that As cannot directly replace P in modern biochemistry. Arsenic (...) is toxic because As and P are similar enough that organisms attempt this substitution. We hypothesize that ancient biochemical systems, analogous to but distinct from those known today, could have utilized arsenate in the equivalent biological role as phosphate. Organisms utilizing such ‘ weird life ’ biochemical pathways may have supported a ‘ shadow biosphere ’ at the time of the origin and early evolution of life on Earth or on other planets. Such organisms may even persist on Earth today, undetected, in unusual niches. (shrink)

We present an exactly soluble electron trajectory that permits an analysis of the soft (deep infrared) radiation emitted, the existence of which has been experimentally observed during beta decay via lowest order inner bremsstrahlung. Our treatment also predicts the time evolution and temperature of the emission, and possibly the spectrum, by analogy with the closely related phenomenon of the dynamic Casimir effect.

The importance of applying game theory to the evolution of information in the presence of noise has recently become widely recognized. This Special Issue addresses the theme of spontaneously emergent order in both classical and quantum systems subject to external noise, and includes papers directly related to game theory or the development of supporting techniques. In the following editorial overview we examine the broader context of the subject, including the tension between the destructive and creative aspects of noise, and foreshadow (...) the significance of some of the subsequent papers in the volume. (shrink)

The problem of life’s origin remains one of the great outstanding challenges to science. Ever since Charles Darwin mused about a “warm little pond” incubating life beneath sunny primeval skies, scientists have speculated about the exact location of this transforming event. Nearly a century and a half later, we remain almost completely ignorant of the physical processes that led from a nonliving chemical mixture to the first autonomous organism. However, some progress at least has been made on tracking down where (...) and when life first established itself on Earth. Fossil evidence suggests that the biological record extends back at least 3.5 billion years, pointing to a still earlier origin1. But this presents a problem. The cratering record of the moon implies that Earth was subjected to intense bombardment by large comets and asteroids over an extended duration until about 3.8 billion years ago. The largest of these impacts would have released enough energy to swathe the planet in incandescent rock vapour, boiling the oceans and sending sterilizing heat pulses a kilometre into the exposed crust2. This unpromising setting – hardly a secure one for warm little ponds – has prompted some astrobiologists to conjecture that life began somewhere else and came to Earth readymade3. Favourite among extraterrestrial originating locations is the planet Mars4. (shrink)