Evolution, the Logic of Biology
eBook - ePub

Evolution, the Logic of Biology

John S. Torday, Virender K. Rehan

Compartir libro
  1. English
  2. ePUB (apto para móviles)
  3. Disponible en iOS y Android
eBook - ePub

Evolution, the Logic of Biology

John S. Torday, Virender K. Rehan

Detalles del libro
Vista previa del libro
Índice
Citas

Información del libro

By focusing on the cellular mechanisms that underlie ontogeny, phylogeny and regeneration of complex physiologic traits, Evolution, the Logic of Biology demonstrates the use of homeostasis, the fundamental principle of physiology and medicine, as the unifying mechanism for evolution as all of biology. The homeostasis principle can be used to understand how environmental stressors have affected physiologic mechanisms to generate condition-specific novelty through cellular mechanisms.

Evolution, the Logic of Biology allows the reader to understand the vertebrate life-cycle as an intergenerational continuum in support of effective, on-going environmental adaptation. By understanding the principles of physiology from their fundamental unicellular origins, culminating in modern-day metazoans, the reader as student, researcher or practitioner will be encouraged to think in terms of the prevention of disease, rather than in the treatment of disease as the eradication of symptoms. By tracing the ontogeny and phylogeny of this and other phenotypic homologies, one can perceive and understand how complex physiologic traits have mechanistically evolved from their simpler ancestral and developmental origins as cellular structures and functions, providing a logic of biology for the first time.

Evolution, the Logic of Biology will be an invaluable resource for graduate students and researchers studying evolutionary development, medicine and biology, anthropology, comparative and developmental biology, genetics and genomics, and physiology.

Preguntas frecuentes

¿Cómo cancelo mi suscripción?
Simplemente, dirígete a la sección ajustes de la cuenta y haz clic en «Cancelar suscripción». Así de sencillo. Después de cancelar tu suscripción, esta permanecerá activa el tiempo restante que hayas pagado. Obtén más información aquí.
¿Cómo descargo los libros?
Por el momento, todos nuestros libros ePub adaptables a dispositivos móviles se pueden descargar a través de la aplicación. La mayor parte de nuestros PDF también se puede descargar y ya estamos trabajando para que el resto también sea descargable. Obtén más información aquí.
¿En qué se diferencian los planes de precios?
Ambos planes te permiten acceder por completo a la biblioteca y a todas las funciones de Perlego. Las únicas diferencias son el precio y el período de suscripción: con el plan anual ahorrarás en torno a un 30 % en comparación con 12 meses de un plan mensual.
¿Qué es Perlego?
Somos un servicio de suscripción de libros de texto en línea que te permite acceder a toda una biblioteca en línea por menos de lo que cuesta un libro al mes. Con más de un millón de libros sobre más de 1000 categorías, ¡tenemos todo lo que necesitas! Obtén más información aquí.
¿Perlego ofrece la función de texto a voz?
Busca el símbolo de lectura en voz alta en tu próximo libro para ver si puedes escucharlo. La herramienta de lectura en voz alta lee el texto en voz alta por ti, resaltando el texto a medida que se lee. Puedes pausarla, acelerarla y ralentizarla. Obtén más información aquí.
¿Es Evolution, the Logic of Biology un PDF/ePUB en línea?
Sí, puedes acceder a Evolution, the Logic of Biology de John S. Torday, Virender K. Rehan en formato PDF o ePUB, así como a otros libros populares de Biowissenschaften y Zellbiologie. Tenemos más de un millón de libros disponibles en nuestro catálogo para que explores.

Información

Editorial
Wiley
Año
2017
ISBN
9781118729281
Edición
1
Categoría
Zellbiologie

1
Introduction

There are these two young fish swimming along, and they happen to meet an older fish swimming the other way, who nods at them and says, “Morning, boys. How's the water?” And the two young fish swim on for a bit, and then eventually one of them looks over at the other and goes "What the hell is water?"
David Foster Wallace, Kenyon College Commencement Speech, 2005
The premise of this book is that the Big Bang of the Universe gave rise to inorganic and organic compounds alike. Both are formed by bonds, the former constituted by inertness, the latter doing quite the opposite by giving rise to life itself. Organic chemistry provided the physical space within which negentropy, chemiosmosis, and homeostasis all acted in concert to form the first primitive cells. Single‐celled organisms dominated the Earth for the first 3 or 4 billion years, followed by the generation of multicellular organisms as exaptations. How and why this occurred provides the mechanism for the emergence of human biology, starting with the “first principles of physiology.” Such a rendering is way overdue, since the human genome was published more than a decade and a half ago. Without such an effectively predictive working model for physiology, such information is of little value.

Mind the Gap

Let us go then, you and I,
When the evening is spread out against the sky
Like a patient etherized upon a table…
T.S. Eliot, The Love Song of J. Alfred Prufrock
The Michelson–Morley experiment (1887) refuted the notion of luminiferous aether, a theorized medium for the propagation of light, making way for novel thinking about the fundamental principles of physics at the close of the nineteenth century and the beginning of the twentieth. This second scientific revolution was crowned by Relativity Theory (1905), equating energy and mass, a counterintuitive relationship that changed not only the way we see the world around us, but also how we see ourselves. The understanding of the inner workings of the Bohr atom similarly gave insights to physics and chemistry that were previously inaccessible and inconceivable. The twenty‐first century has been declared the “age of biology,” given our foreknowledge of the genetic makeup of humans and an ever‐increasing number of model organisms. Yet the promise of the human genome – the cure for all of our medical ills – has not transpired 15 years hence. We contend that this is symptomatic of our not having attained the level of knowledge in biology that the physicists had reached at the dawn of the second scientific revolution…we are still mired in the sticky, sludgy, stodgy “aether” of descriptive biology. Deep understanding of the inner workings of the cell, particularly as they have facilitated the evolution of multicellular organisms, will herald such breakthrough science. The way in which the cell acts at the interface between the external physical and internal biological “worlds,” authoring the script for Life, is a reality play without an ending, reiterative and reinventive. Thus life is formulated to continually learn from the ever‐changing environment, making use of such knowledge in order to sustain and perpetuate it.

Duality, Serendipity, and Discovery

The field of biomedical research is characterized by paradoxes, serendipitous observations, and occasional discoveries. This is due to the lack of a central theory of biology, DNA notwithstanding. It is also the reason why we have been unable to solve the challenging “puzzle” of evolution. In lieu of guidelines and principles, we collect anecdotes and make up “Just So” stories based on associations and a posteriori reasoning. This book was written to elucidate how to understand biology based on its origins in unicellular life, evolving in the forward direction of biologic history, both ontogenetically (short‐term history) and phylogenetically (long‐term history). We use the figure‐ground image (Figure 1.1), made popular by gestalt psychology, as a way to express the inherent problem in seeing biologic phenomena as dualities: inorganic‐organic, genotype‐phenotype, proximate‐ultimate, structure‐function, health‐disease, synchronic‐diachronic, ontogeny‐phylogeny. It is the latter duality that was the breakthrough for us, realizing that ontogeny and phylogeny, looked at from a cellular perspective, are actually one and the same process, only seen from different perspectives. With that issue put behind us, we could address the “first principles of physiology,” beginning with the plasmalemma of protists as the homolog for all of the subsequent traits expressed by multicellular organisms.
Illustration of the figure-ground image.
Figure 1.1 Figure‐ground “faces.”

Biology as “Stamp Collecting”

As working scientists, the authors of this book have been involved in studies of developmental physiology for many decades. One of us (J.T.) was first introduced to the concepts of cell biology in reading Paul Weiss, one of the founders of the discipline, when he took advanced placement biology in high school. It was Weiss who admonished us not to ask “how or why” questions, but merely to describe biologic phenomena. That attitude prevailed in biology until the advent of molecular biology in the 1960s, which demanded that we ask how biologic mechanisms functioned, having finally “reduced” the problem to its smallest functional unit, the cell, like the Bohr atom in physics. Yet this reductionist approach has not solved some of the remaining fundamentals of physics, hence string theory, “branes,” and multiverses. By analogy, we are of the opinion that we must think in terms of the cell as the smallest functional unit of biology. Conversely, stripping away billions of years of biologic information to focus on DNA is a systematic error that is misleading and misguided, in our opinion. This book is intended to demonstrate how the cell‐molecular approach to evolutionary biology provides novel insights to the how and why for the evolution of form and function.
The “why” question has emerged from the New Synthesis of evolutionary biology, particularly after it had embraced developmental biology as evo‐devo. But even at that, the evolutionists were not delving into the mechanisms of evolution, seemingly content with random mutation and population selection as the mechanisms of evolution. For working scientists like ourselves, studying how organs develop across species, this didn’t seem like a reasonable process since we could see the common denominator between ontogeny and phylogeny at the cellular level, suggesting (to us) that some underlying organizing principle was at large. Not to mention that the ongoing serendipitous, anecdotal nature of both biology and medicine, even in the post‐Human Genome Project era, was frustrating given that science is ultimately supposed to be predictive.
Then in 2004 Nicole King published her ground‐breaking paper demonstrating for the first time that the complete multicellular genomic “toolkit” of sponges was expressed in the unicellular free‐swimming amoeboid form during the life cycle. That reversed everything in biology because up until that point in time physiology was described based on biologic traits in their extant form, not based on how they evolved from the unicellular state. That perspective precipitated our hypothesis that the complete phenotypic toolkit was present in the plasmalemma of unicellular organisms, and raised the question as to how the genome determined complex physiology ontogenetically and phylogenetically, from unicellular organisms to invertebrates and vertebrates.
That question was made all the more pertinent because we had published a seminal paper on the cell‐molecular basis of alveolar physiology that had emerged from decades‐long study of how the fetal lung develops at the cell‐molecular level. Those studies were catalyzed by two landmark observations – the physiologic acceleration of lung development by glucocorticoids, and the observation that parathyroid hormone‐related protein (PTHrP) was necessary for alveolar formation. The linking of those two phenomena through the serial paracrine interactions between the lung endoderm and mesoderm culminated in our fundamental understanding of the physiologic principle of ventilation‐perfusion matching – essentially how the distension of the alveolar wall molecularly coordinated surfactant production and alveolar capillary perfusion to maintain both local and systemic homeostasis.
The experimental evidence for the coordinating effects of cell stretching on PTHrP, leptin, and their cognate cell‐surface receptors on surfactant production and vascular perfusion led to the first scientific documentation of the physiologic continuum from development to homeostasis. More importantly, it begged the question as to how these specific cell types evolved the mammalian lung phenotype, given that the molecular ligand and receptor intermediates involved were highly conserved, deep homologies that could be traced at least as far back as the origins of vertebrate phylogeny in fish, if not all the way back to the unicellular state. If that “story” could be told, it would provide insight to both lung physiology and pathophysiology based on first principles – a counterintuitive idea predicted by this cell‐molecular approach.
More importantly, the functional genomic linkage between lung evolution in complex climax organisms – mammals and birds – and homologous mechanisms in emerging unicellular eukaryotes, formed the basis for fundamental insights into the evolution of all visceral organs. The advent of cholesterol, which Konrad Bloch referred to as a “molecular fossil,” was critical for the evolution of eukaryotes from prokaryotes. The insertion of cholesterol into the cell membrane of eukaryotes enabled vertebrate evolution by facilitating endocytosis (cell eating), increased gas exchange (due to the thinning of the eukaryotic cell membrane), and increased locomotion (due to increased cytoplasmic streaming). And vertebrate evolution is founded on those three biologic traits – metabolism, respiration, and locomotion. Therefore, all of the visceral organs – lung, kidney, skin, skeleton, brain, and so forth – likely evolved from the plasmalemmae of unicellular organisms, providing a unified, common homolog for all of these organs. The existence of vertebrate physiologic mechanisms based on functional cell‐molecular homologies, rather than on the tautologic “Just So” stories for physiologic structure and function that currently prevail, would no longer hamper forward progress in understanding the “how” and “why” of biology and medicine.
Up until now, the void between descriptive and mechanistic physiology has been filled by either top‐down descriptive physiology, or bottom‐up abstract philosophy and mathematics. With the insights gained from the “middle‐out” ligand‐receptor approach we have employed to understand lung evolution, we are now enabled for a paradigm shift from post‐dictive to predictive physiology and medicine.
Historically, physicists became actively involved in biology after the Second World War as an alternative source of employment, having successfully developed and deployed the atomic bomb. The Greek philosophers understood the unity of life intellectually as far back in written history as the fifth century BCE, but had no scientific evidence for it. Beginning with quantum mechanics, physicists felt empowered to comment on the meaning of life, given that they had discovered the operating principle behind the atom and had unleashed its power. Bohr was the first modern physicist to address the question of “what is life” by applying the conceptual principle of the duality of light to biology in his Como lecture in 1927. He went on to explain that this seeming duality was a technical glitch due to the different ways in which the wave and packet forms of light were measured, a phenomenon he referred to as complementarity. T...

Índice