Evolution Without Genes: A Review

2019 ◽  
Vol 1 (1) ◽  
pp. 45-68
Author(s):  
Abyt Ibraimov
Keyword(s):  
Modern Synthesis ◽  
Mitotic Chromosomes ◽  
Noncoding Dna ◽  
Theory Of Evolution ◽  
Leading Role ◽  
Material Basis ◽  
Scientific Hypothesis ◽  
Species Formation ◽  
Evolutionary Changes ◽  
Eukaryotic Organisms

Evolution is a proven scientific fact. However, its mechanism is unknown. Modern Synthesis, the generally accepted theory of evolution is centered on species formation and population dynamics. According to Modern Synthesis, genes are considered the material basis of evolution. This circumstance is considered as the main obstacle in elucidating the mechanisms of evolution. It is proposed that any scientific hypothesis trying to explain the evolution of eukaryotes should meet the following requirement: all important evolutionary changes (nucleosomes, mitotic chromosomes, chromosome bands, cell nucleus, eukaryotic cells, sex, species, multicellular and homeothermic organisms, including modern humans) should occur based on one component of the genome. As is known, the genome of eukaryotic organisms consists of two components: euchromatin (coding DNA) and heterochromatin (noncoding DNA). A hypothesis is proposed that the evolution of eukaryotes occurred on the basis of a non-coding part of the genome. Therefore, with the advent of eukaryotic organisms, the material basis of evolution has evolved and noncoding DNAs have begun to play a leading role.  

Challenging the Modern Synthesis

2017 ◽  
Keyword(s):  
21St Century ◽  
Evolutionary Biology ◽  
Modern Synthesis ◽  
Early 20Th Century ◽  
Theory Of Evolution ◽  
Original Essays ◽  
New Biology ◽  
Conceptual Foundations ◽  
Orthodox View

Since its origin in the early 20th century, the modern synthesis theory of evolution has grown to represent the orthodox view on the process of organic evolution. It is a powerful and successful theory. Its defining features include the prominence it accords to genes in the explanation of development and inheritance, and the role of natural selection as the cause of adaptation. Since the advent of the 21st century, however, the modern synthesis has been subject to repeated and sustained challenges. In the last two decades, evolutionary biology has witnessed unprecedented growth in the understanding of those processes that underwrite the development of organisms and the inheritance of characters. The empirical advances usher in challenges to the conceptual foundations of evolutionary theory. Many current commentators charge that the new biology of the 21st century calls for a revision, extension, or wholesale rejection of the modern synthesis theory of evolution. Defenders of the modern synthesis maintain that the theory can accommodate the exciting new advances in biology, without forfeiting its central precepts. The original essays collected in this volume—by evolutionary biologists, philosophers of science, and historians of biology—survey and assess the various challenges to the modern synthesis arising from the new biology of the 21st century. Taken together, the essays cover a spectrum of views, from those that contend that the modern synthesis can rise to the challenges of the new biology, with little or no revision required, to those that call for the abandonment of the modern synthesis.

The Modern Synthesis is Partly Wright

Paleobiology ◽  
1981 ◽  
Vol 7 (1) ◽  
pp. 128-131 ◽  
Author(s):  
Steven Hecht Orzack
Keyword(s):  
General Theory ◽  
Modern Synthesis ◽  
Theory Of Evolution

Gould (1980) claims that a “new and general theory of evolution” is emerging. He examines the modern synthesis and asserts that it is being rejected by present day evolutionary biologists. The purpose of this note is to show that Gould's view of the modern synthesis is distorted. Any rejection of the modern synthesis must rest on a more balanced characterization than that presented by Gould.

scholarly journals Structural basis for the absence of low-energy chlorophylls responsible for photoprotection from a primitive cyanobacterial PSI

2021 ◽  
Author(s):  
Koji Kato ◽  
Tasuku Hamaguchi ◽  
Ryo Nagao ◽  
Keisuke Kawakami ◽  
Yoshifumi Ueno ◽  
...  
Keyword(s):  
Co2 Fixation ◽  
Energy Levels ◽  
Low Energy ◽  
Structural Basis ◽  
Photosynthetic Organisms ◽  
Cryo Electron Microscopy ◽  
Evolutionary Changes ◽  
Eukaryotic Organisms ◽  
Pigment Protein Complex ◽  
Resolution Structure

Photosystem I (PSI) of photosynthetic organisms is a multi-subunit pigment-protein complex and functions in light harvesting and photochemical charge-separation reactions, followed by reduction of NADP to NADPH required for CO2 fixation. PSI from different photosynthetic organisms has a variety of chlorophylls (Chls), some of which are at lower-energy levels than its reaction center P700, a special pair of Chls, and are called low-energy Chls. However, the site of low-energy Chls is still under debate. Here, we solved a 2.04-Å resolution structure of a PSI trimer by cryo-electron microscopy from a primitive cyanobacterium Gloeobacter violaceus PCC 7421, which has no low-energy Chls. The structure showed absence of some subunits commonly found in other cyanobacteria, confirming the primitive nature of this cyanobacterium. Comparison with the known structures of PSI from other cyanobacteria and eukaryotic organisms reveals that one dimeric and one trimeric Chls are lacking in the Gloeobacter PSI. The dimeric and trimeric Chls are named Low1 and Low2, respectively. Low2 does not exist in some cyanobacterial and eukaryotic PSIs, whereas Low1 is absent only in Gloeobacter. Since Gloeobacter is susceptible to light, this indicates that Low1 serves as a main photoprotection site in most oxyphototrophs, whereas Low2 is involved in either energy transfer or energy quenching in some of the oxyphototrophs. Thus, these findings provide insights into not only the functional significance of low-energy Chls in PSI, but also the evolutionary changes of low-energy Chls responsible for the photoprotection machinery from photosynthetic prokaryotes to eukaryotes.

Evolution at All Scales in the Vertebrate Fossil Record

2002 ◽  
Vol 11 ◽  
pp. 165-178
Author(s):  
John P. Hunter
Keyword(s):  
Fossil Record ◽  
Large Scale ◽  
Large Time ◽  
Evolutionary Change ◽  
Theory Of Evolution ◽  
Evolutionary Forces ◽  
The Past ◽  
Evolutionary Changes ◽  
Abundant Evidence ◽  
Transitional Forms

The fossil record of vertebrates provides abundant evidence for both the fact and the theory of evolution (Carroll, 1997; Prothero and Schoch, 1994). In support of the fact that evolution has indeed occurred, the vertebrate fossil record clearly documents evolutionary change along lineages, that is, along direct lines of ancestors and descendents. The fossil record also shows step-wise evolutionary changes resulting in the emergence of new kinds of vertebrates from pre-existing kinds—for example, the origin of mammals from the “mammal-like” reptiles. In support of the theory that natural selection, in particular, has been largely responsible for evolutionary change, the fossil record shows that the numerous “transitional” forms that lived in the past—far from being nonviable “monsters”—were functionally integrated organisms that were well adapted to their ecological roles. Finally, the vertebrate fossil record preserves certain large-scale phenomena, such as radiations and trends, which show that evolutionary forces can act over very large time scales.

Development of Wallace's Perception of Biogeography, 1848-1859

1985 ◽  
Vol 4 (2) ◽  
pp. 113-117 ◽  
Author(s):  
John Brooks
Keyword(s):  
Geographical Distribution ◽  
Related Species ◽  
Comprehensive Treatment ◽  
Evolutionary Perspective ◽  
Theory Of Evolution ◽  
Alfred Russel Wallace ◽  
Species Formation ◽  
Active Interest ◽  
The Subject ◽  
The Relationship

Alfred Russel Wallace produced his two-volume treatise, Geographical Distribution of Animals, the first comprehensive treatment with an evolutionary perspective, in 1876. His active interest in the subject, however, began three decades earlier. In 1848, he embarked for Amazonia to seek evidence for species formation by examining the relationship between the distribution and affinity of related species. A series of papers based on his discoveries in the following decade presented not only Wallace's theory of evolution but also his concept of the regional aspects of geographical distribution as the resultant of both physiographic events and the origin and extinction of species. These conceptual papers were all published before Charles Darwin's, On the Origin of species (1859).

Heredity, evolution and development in their (epistemic) environment at the turn of the nineteenth century

2016 ◽  
Vol 49 (1) ◽  
pp. 107-113
Author(s):  
Federica Turriziani Colonna
Keyword(s):  
Nineteenth Century ◽  
Twentieth Century ◽  
Life Sciences ◽  
Research Facility ◽  
Evolution And Development ◽  
Family Wealth ◽  
Material Basis ◽  
Evolutionary Changes ◽  
The One ◽  
Anton Dohrn

During the early 1870s a young zoologist who worked as a Privatdozent delivering lectures at different Prussian universities invested much of his family wealth and solicited his fellows' contributions to establish a research facility by the sea. The young zoologist happened to be called Anton Dohrn. From the time it opened its doors, the Anton Dohrn Zoological Station – or Naples Zoological Station, as it was originally called – played a crucial role in shaping life sciences as it facilitated research aimed at explaining the mechanics of inheritance. During the last quarter of the nineteenth century and the first decades of the twentieth, zoologists attempted to explain how evolutionary changes occur within a population and become stabilized. In so doing, they looked at developmental processes as well as environmental pressure, coming up with different hypotheses to explain inheritance. In some cases, their research was highly speculative, whereas in other cases they conducted cytological observations to identify the material basis of heredity. Research on evolution and development has been carried out in different places, and zoological stations like the one in Naples have played a major role in this story. However, numerous biological institutions active at the turn of the twentieth century have not received much attention from historians.

Evolution at all Scales in the Vertebrate Fossil Record

1999 ◽  
Vol 9 ◽  
pp. 203-220 ◽  
Author(s):  
John P. Hunter
Keyword(s):  
Fossil Record ◽  
Large Scale ◽  
Large Time ◽  
Evolutionary Change ◽  
Theory Of Evolution ◽  
Evolutionary Forces ◽  
The Past ◽  
Evolutionary Changes ◽  
Abundant Evidence ◽  
Transitional Forms

The fossil record of vertebrates provides abundant evidence for both the fact and the theory of evolution (Carroll, 1997; Prothero and Schoch, 1994). In support of the fact that evolution has indeed occurred, the vertebrate fossil record clearly documents evolutionary change along lineages, that is, along direct lines of ancestors and descendents. The fossil record also shows step-wise evolutionary changes resulting in the emergence of new kinds of vertebrates from pre-existing kinds, for example, the origin of mammals from the “mammal-like” reptiles. In support of the theory that natural selection, in particular, has been largely responsible for evolutionary change, the fossil record shows that the numerous “transitional” forms that lived in the past — far from being nonviable “monsters” — were functionally integrated organisms that were well adapted to their ecological roles. Finally, the vertebrate fossil record preserves certain large-scale phenomena, such as radiations and trends, which show that evolutionary forces can act over very large time scales.

Objectcy and Agency

2018 ◽  
Author(s):  
Denis M. Walsh
Keyword(s):  
Adaptive Evolution ◽  
Natural World ◽  
Modern Synthesis ◽  
Scientific Theories ◽  
Object Theory ◽  
Theory Of Evolution ◽  
Agent Theory ◽  
Comprehensive Account ◽  
The Difference ◽  
The Way

Organisms are like nothing else in the natural world. They are agents. Methodological vitalism is a view according to which the difference that organisms make to the natural world cannot be captured wholly if we treat them as mere objects. Understanding agency calls for a different kind of theory, an agent theory. Most of our scientific theories are object theories. The modern synthesis theory of evolution is a prominent example of object theory. Being the way it is, it cannot countenance the contribution to evolution that organisms make as agents. A comprehensive account of adaptive evolution requires an agent theory.

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