Evolutionary Choice Research Articles

Evolutionary choice between cholesterol and ergosterol

Sterol biosynthesis has evolved early in the history of eukaryotes. In most animals, as well as in primitive fungi, the main sterol is cholesterol. During the process of evolution, fungi acquired the ability to synthesize ergosterol. The pathway of its biosynthesis is more complex than the one of cholesterol biosynthesis. However, the evolutionary choice of most fungi was ergosterol, and the reason for this choice is still debated. In the majority of the works on this issue, the choice of most fungi is associated with the transition to life on land, and, consequently, the danger of cell dehydration. In our review we oppose this point of view. Probably, compared to cholesterol, ergosterol has more pronounced antioxidant properties. Indeed, the presence of three double bonds in the structure of the ergostеrol molecule, as compared to one in cholesterol, relatively increases the likelihood of interaction with reactive oxygen species. Perhaps, the transition to life on land required additional antioxidant protection. Due to the aforementioned structural differences, the molecule of cholesterol is apparently more flexible than that of ergosterol. Experimental data indicate that this feature provides greater membrane flexibility as compared to fungal membranes, as well as a greater ability to compensate for disturbances in the packing of membrane phospholipids. Presumably, for animal cells these qualities turned out to be relatively more important than antioxidant ones, which predetermined their evolutionary choice of sterol.

Evolutionary Choice between Cholesterol and Ergosterol

Evolutionary Choice between Cholesterol and Ergosterol

History of the Red Nucleus, its Tracts and Species Evolutionary Choice

History of the Red Nucleus, its Tracts and Species Evolutionary Choice

The impact of evolved psychological mechanisms on innovation and adoption: A systematic literature review

Studies of the impact of psychological factors and cognitive decision processes, which are often regarded as micro-foundations of innovation and adoption, are a dominant theme in the recent innovation literature. Across a range of disciplines, analysis of the role of evolved psychological mechanisms (EPM) in decision-making has led to dramatic changes in our understanding of motivation and the mechanisms of decision-making. However, the emerging literature applying these findings to innovation and technology management has not been thoroughly assessed. Given the substantial advances in psychology and economics generated by the application of an EPM lens, we undertake a systematic review of innovation, adoption, and resistance literature in which EPMs are applied or considered. This paper synthesizes the existing literature, describes the influence of EPMs on decisions involving new ideas or technologies, proposes Evolutionary Choice Theory (ECT) as a parsimonious and consilient theory of decision-making, and offers pragmatic insights for practitioners to support consistent and effective managerial interventions.

HOW DO PSYCHOLOGICAL FACTORS AFFECT INNOVATION AND ADOPTION DECISIONS?

Interest in the significant impact of psychological factors on innovation outcomes is growing rapidly. Our understanding of cognitive processes is, however, evolving, and research on the specific forms and role of these factors within innovation-related decisions is limited. We propose a theory of decision-making that offers consilience across research areas, is grounded in both physical and social sciences, explains the constructs already established by innovation, adoption and resistance research, and serves the needs of innovation researchers and practitioners as a pragmatic tool. Using a variety of established research tools in novel ways including semantic field and bibliometric analysis and by drawing on research from diverse disciplines, we identify evolved psychological mechanisms as influences on adoption decision processes. We conclude that Evolutionary Choice Theory, defined as the collective influence of these evolved psychological mechanisms, should be adopted by innovation practitioners and researchers and provide specific pragmatic applications to inform this adoption.

The Evolutionary Fate of Mitochondrial Aminoacyl-tRNA Synthetases in Amitochondrial Organisms

During the endosymbiotic evolution of mitochondria, the genes for aminoacyl-tRNA synthetases were transferred to the ancestral nucleus. A further reduction of mitochondrial function resulted in mitochondrion-related organisms (MRO) with a loss of the organelle genome. The fate of the now redundant ancestral mitochondrial aminoacyl-tRNA synthetase genes is uncertain. The derived protein sequence for arginyl-tRNA synthetase from thirty mitosomal organisms have been classified as originating from the ancestral nuclear or mitochondrial gene and compared to the identity element at position 20 of the cognate tRNA that distinguishes the two enzyme forms. The evolutionary choice between loss and retention of the ancestral mitochondrial gene for arginyl-tRNA synthetase reflects the coevolution of arginyl-tRNA synthetase and tRNA identity elements.

Clocks, Hourglasses, and History‐dependent Clocks

Many organisms have free-running circadian clocks to anticipate the time of the day, including the Kai protein-based clock in the cyanobacterium Synechococcus elongatus. However, other species have an ‘hourglass’ timer, such as the cyanobacterium Prochlorococcus marinus. What conditions favor an hourglass timer or a free running clock over the other? We argue that this evolutionary choice is influenced by the noise levels in the external environment (e.g., light fluctuations due to weather) relative to noise levels in the internal environment of the cell (e.g., molecular fluctuations). Besides different clock dynamics in different species, we find that the clock of a single species, S. elongatus, exploits a clock-metabolic coupling to tune its clock dynamics towards an hourglass timer to deal with changing noise levels.

HOW DO PARTIALLY HIDING BEHAVIOR AND COMPLETELY HIDING BEHAVIOR IMPACT INTERACTING POPULATIONS?

As the two main behaviors of prey populations in ecological systems, the partially hiding behavior (PHB) and the completely hiding behavior (CHB) play a significant role in determining the dynamics of predator–prey models. This work examines to the dynamical consequences of predator–prey systems with the PHB and the CHB. Previous research has independently studied the two behaviors, and the general conclusions are that the two behaviors can have positive and/or negative impacts on the considered population models. However, to our knowledge, no study has combined and compared the two behaviors in studying the dynamical consequences of predation interactions. Motivated by this, we investigated the dynamical consequences induced by the PHB and the CHB. From a mathematical point of view, the dynamical behaviors are studied and the corresponding sufficient conditions are given. Our findings are general and some published models are special cases of ours. From an ecological point of view, we find that the size of the ecological regions is mainly determined by the two behaviors, and which one is ecologically beneficial for the health coexistence of the interacting populations are primarily determined by the functional response and the attack coefficient of predators. Moreover, we conclude that the evolutionary and optimal choices of prey behavior (PHB or CHB) depend on the predators attack coefficient (large or small attack coefficient) and the resource level (abundant or pool resource level).

Clocks, Hourglasses, and History‐dependent Clocks

Many organisms have free‐running circadian clocks to anticipate the time of the day, including the Kai protein‐based clock in the cyanobacterium Synechococcus elongatus. However, other species have an ‘hourglass’ timer, such as the cyanobacterium Prochlorococcus marinus. What conditions favor an hourglass timer or a free running clock over the other? We argue that this evolutionary choice is influenced by the noise levels in the external environment (e.g., light fluctuations due to weather) relative to noise levels in the internal environment of the cell (e.g., molecular fluctuations). Besides different clock dynamics in different species, we find that the clock of a single species, S. elongatus, exploits a clock‐metabolic coupling to tune its clock dynamics towards an hourglass timer to deal with changing noise levels.Support or Funding InformationK.H. thanks the James S. McDonnell Foundation for support via a Postdoctoral Fellowship. A.M. thanks the Simons Foundation for support.

Evolution of C4 photosynthesis predicted by constraint-based modelling.

Constraint-based modelling (CBM) is a powerful tool for the analysis of evolutionary trajectories. Evolution, especially evolution in the distant past, is not easily accessible to laboratory experimentation. Modelling can provide a window into evolutionary processes by allowing the examination of selective pressures which lead to particular optimal solutions in the model. To study the evolution of C4 photosynthesis from a ground state of C3 photosynthesis, we initially construct a C3 model. After duplication into two cells to reflect typical C4 leaf architecture, we allow the model to predict the optimal metabolic solution under various conditions. The model thus identifies resource limitation in conjunction with high photorespiratory flux as a selective pressure relevant to the evolution of C4. It also predicts that light availability and distribution play a role in guiding the evolutionary choice of possible decarboxylation enzymes. The data shows evolutionary CBM in eukaryotes predicts molecular evolution with precision.

Thermally Modified Iron-Inserted Calcium Phosphate for Magnetic Hyperthermia in an Acceptable Alternating Magnetic Field.

Magnetic hyperthermia treatment using calcium phosphate nanoparticles is an evolutionary choice because of its excellent biocompatibility. In the present work, Fe3+ is incorporated into HAp nanoparticles by thermal treatment at various temperatures. Induction heating was examined within the threshold H f value of 4.58 × 106 kA m-1 s-1 (H is the strength of alternating magnetic field and f is the operating frequency) and sample concentration of 10 mg/mL. The temperature-dependent structural modifications are well correlated with the morphological, surface charge, and magnetic properties. Surface charge changes from +10 mV to -11 mV upon sintering because of the diffusion of iron in the HAp lattice. The saturation magnetization has been achieved by sintering the nanoparticles at 400 and 600 °C, which has led to the specific absorption rate of 12.2 and 37.2 W/g, respectively. Achievement of the hyperthermia temperature (42 °C) within 4 min is significant when compared with the existing magnetic calcium phosphate nanoparticles. The systematic investigation reveals that the HAp nanoparticles partially stabilized with FeOOH and biocompatible α-Fe2O3 exhibit excellent induction heating. In vitro tests confirmed the samples are highly hemocompatible. The importance of the present work lies in HAp nanoparticles exhibiting induction heating without compromising the factors such as H f value, low sample concentration, and reduced duration of applied field.

The Origin of Diversification: An Evolutionary Theory

Diversification is a fundamental concept in economics, decision theory and finance. It also lies at the core of the Darwinian evolution argument, and diversifying behavior known as bet-hedging has been widely documented in other species. The central premise of this paper is that attitudes towards diversification are, at least in part, the evolutionary product of natural selection. The main contribution consists of an evolutionary choice model relating diversifying behavior to evolutionary fitness, which is used to prove that diversification is advantageous from an evolutionary perspective. Two situations are distinguished: in the model under risk, when probabilities of future reproductive success are known, natural selection favours the traditional mean-variance diversification strategy, whereas in the model under uncertainty, when probabilities are unknown, the naive diversification heuristic and the related principle of insufficient reason emerge as maximizing evolutionary fitness. These insights into the potentially biological origins of diversifying behavior may have implications for how one can treat observed anomalies in practice.

Molecular Requirements of High-Fidelity Replication-Competent DNA Backbones for Orthogonal Chemical Ligation.

The molecular properties of the phosphodiester backbone that made it the evolutionary choice for the enzymatic replication of genetic information are not well understood. To address this, and to develop new chemical ligation strategies for assembly of biocompatible modified DNA, we have synthesized oligonucleotides containing several structurally and electronically varied artificial linkages. This has yielded a new highly promising ligation method based on amide backbone formation that is chemically orthogonal to CuAAC "click" ligation. A study of kinetics and fidelity of replication through these artificial linkages by primer extension, PCR, and deep sequencing reveals that a subtle interplay between backbone flexibility, steric factors, and ability to hydrogen bond to the polymerase modulates rapid and accurate information decoding. Even minor phosphorothioate modifications can impair the copying process, yet some radical triazole and amide DNA backbones perform surprisingly well, indicating that the phosphate group is not essential. These findings have implications in the field of synthetic biology.

Type I Interferons in Newborns-Neurotoxicity versus Antiviral Defense.

ABSTRACTIn most children and adults, primary infection with herpes simplex virus 1 (HSV-1) is asymptomatic. However, very rarely (incidence of 1 in 1,000,000), it can cause herpes simplex encephalitis (HSE). HSE also occurs in infants but with a much starker incidence of one in three. This age difference in susceptibility to HSV-1-caused HSE is not well understood. In a recent article in mBio, authors have identified the choroid plexus as the anatomical site of robust HSV-1 replication in the brain. They point to low levels of type I interferon (IFN) receptor as causal of the lack of HSV-1 replication control in neonates, in contrast to adults. Here, I discuss these findings in the context of human genetic evidence. I point to the balancing act of type I IFN acting as a neurotoxin and an antiviral agent, an evolutionary choice of a lesser evil.

Humanity Rising

The main paradigm we presently use to understand our universe is theoretical physics. It has helped us understand much about space, time, energy, and matter but does not presently explain or predict the emergence of information, computation, life, and mind. In biological systems, the discipline of evolutionary development (evo-devo) biology studies how evolutionary and developmental processes interact to guide the production of ordered, complex, adaptive, and intelligent structures. In living systems, we can distinguish evolutionary processes, which are stochastic, variety-creating, divergent, and contingently adaptive, and developmental processes, which produce convergent and systemically statistically predictable structures and trajectories in a hierarchical developmental cycle, from seed, to adult, to reproduction, aging, and death. If our universe is also a cycling, evo devo system, that moves from seed, to adult, to reproduction and death, as several scientists and philosophers now suspect, it must also exhibit both unpredictable evolutionary creativity over its life span and many predictable and constraining developmental constants, functions, and futures, as it grows up, reproduces, and dies. As science learns to see our universe as an evo-devo system, our foresight will greatly improve, and humanity will gain new moral responsibilities, both to predict and help developmental processes unfold, and to increase evolutionary free choice and diversity of paths.

Parameter asymmetry and time‐scale separation in core genetic commitment circuits

Theory allows studying why Evolution might select core genetic commitment circuit topologies over alternatives. The nonlinear dynamics of the underlying gene regulation together with the unescapable subtle interplay of intrinsic biochemical noise impact the range of possible evolutionary choices. The question of why certain genetic regulation circuits might present robustness to phenotype‐delivery breaking over others, is therefore of high interest. Here, the behavior of systematically more complex commitment circuits is studied, in the presence of intrinsic noise, with a focus on two aspects relevant to biology: parameter asymmetry and time‐scale separation. We show that phenotype delivery is broken in simple two‐ and three‐gene circuits. In the two‐gene circuit, we show how stochastic potential wells of different depths break commitment. In the three‐gene circuit, we show that the onset of oscillations breaks the commitment phenotype in a systematic way. Finally, we also show that higher dimensional circuits (four‐gene and five‐gene circuits) may be intrinsically more robust.

The competition between simple and complex evolutionary trajectories in asexual populations.

BackgroundOn rugged fitness landscapes where sign epistasis is common, adaptation can often involve either individually beneficial “uphill” mutations or more complex mutational trajectories involving fitness valleys or plateaus. The dynamics of the evolutionary process determine the probability that evolution will take any specific path among a variety of competing possible trajectories. Understanding this evolutionary choice is essential if we are to understand the outcomes and predictability of adaptation on rugged landscapes.ResultsWe present a simple model to analyze the probability that evolution will eschew immediately uphill paths in favor of crossing fitness valleys or plateaus that lead to higher fitness but less accessible genotypes. We calculate how this probability depends on the population size, mutation rates, and relevant selection pressures, and compare our analytical results to Wright-Fisher simulations.ConclusionWe find that the probability of valley crossing depends nonmonotonically on population size: intermediate size populations are most likely to follow a “greedy” strategy of acquiring immediately beneficial mutations even if they lead to evolutionary dead ends, while larger and smaller populations are more likely to cross fitness valleys to reach distant advantageous genotypes. We explicitly identify the boundaries between these different regimes in terms of the relevant evolutionary parameters. Above a certain threshold population size, we show that the probability that the population finds the more distant peak depends only on a single simple combination of the relevant parameters.

On the biogenic origins of homochirality.

Homochirality, the single-handedness of optically asymmetric chemical structures, is present in all major biological macromolecules. Terrestrial life's preference for one isomer over its mirror image in D-sugars and L-amino acids has both fascinated and puzzled biochemists for over a century. But the contrasting case of the equally fundamental phospholipids has received less attention. Although the phospholipid glycerol headgroups of archaea and bacteria are both exclusively homochiral, the stereochemistries between the two domains are opposite. Here I argue that the reason for this "dual homochirality" was a simple evolutionary choice at the independent origin of the two synthesizing enzymes. More broadly, this points to a trivial biogenic cause for the evolution of homochirality: the enzymatic processes that produce chiral biomolecules are stereospecific in nature. Once an orientation has been favored, shifting to the opposite is both difficult and unnecessary. Homochirality is thus the simplest and most parsimonious evolutionary case.

Evolutionary governance choice for corporate social responsibility: a forestry campaign case in South Korea

Firms select different governance types (e.g. internalisation, outsourcing or collaboration) for corporate social responsibility (CSR) activities. This paper examined how the choice of CSR governance type is influenced by social factors and organisational experiences and how changes in these factors affect the governance choice. These questions are especially meaningful in the context of developing countries with weak institutional environments and recent social change. With the unique phenomenon that is not readily explainable in terms of the extant theoretical groundwork on CSR governance choice, a case study of a South Korean forestry campaign by Yuhan-Kimberly was analysed. It was found that social circumstances triggered Yuhan-Kimberly's initiation of forestry projects, but the absence of social infrastructure limited the choice of governance type early on. Lack of experience also constrained the governance choice. Over time, environmental change and the accumulation of organisational knowledge caused the choice of governance to evolve. This study contributes to the CSR governance choice literature by exploring social and organisational determinants other than economic efficiency and by applying a dynamic perspective.

A Maternal Factor Unique to Ascidians Silences the Germline via Binding to P-TEFb and RNAP II Regulation

Suppression of zygotic transcription in early embryonic germline cells is tightly linked to their separation from the somatic lineage. Many invertebrate embryos utilize localized maternal factors that are successively inherited by the germline cells for silencing the germline. Germline quiescence has also been associated with the underphosphorylation of Ser2 of the C-terminal domain (CTD-Ser2) of RNA polymerase II [1-3]. Here, using the ascidian Halocynthia roretzi, we identified a first deuterostome example of a maternally localized factor, posterior end mark (PEM), which globally represses germline transcription. PEM knockdown resulted in ectopic transcription and ectopic phosphorylation of CTD-Ser2 in the germline. Overexpression of PEM abolished all transcription and led to the underphosphorylation of CTD-Ser2 in the somatic cells. PEM protein was reiteratively detected in the nucleus of the germline cells and coimmunoprecipitated with CDK9, a component of posterior transcription elongation factor b (P-TEFb). These results suggest that nonhomologous proteins, PEM and Pgc of Drosophila [3-5] and PIE-1 of C. elegans [1, 6, 7], repress germline gene expression through analogous functions: by keeping CTD-Ser2 underphosphorylated through binding to the P-TEFb complex. The present study is an interesting example of evolutionary constraint on how a mechanism of germline silencing can evolve in diverse animals.