Chromosomes selection evolutionary. Medical search. Frequent questions

In our evolutionary past, these so-called niche construction effects occasionally created the necessary and sufficient condition for natural selection: a generationally persistent covariance between genes and fitness. (edge.org)
The long-term undifferentiation of molluscan sex chromosomes is potentially sustained by the unexpected intertwined regulation of reversible sex-biased genes, together with the lack of sexual dimorphism and occasional sex chromosome turnover. (nature.com)
The pleiotropic constraint of regulation of reversible sex-biased genes is widely present in ancient homomorphic sex chromosomes and might be resolved in heteromorphic sex chromosomes through gene duplication followed by subfunctionalization. (nature.com)
The evolutionary dynamics of sex chromosomes suggest a mechanism for 'inheritance' turnover of sex-determining genes that is mediated by translocation of a sex-determining enhancer. (nature.com)
I have an idea that the Y chromosome is the location for the development of new genes. (ideaoffer.com)
My speculation is new genes are made on one end of the Y chromosome and if they survive sexual, environmental and other selection pressures, there is a time keeping process. (ideaoffer.com)
A teasing out of the logic that makes it worthwhile for an organism to try out new genes all by themselves on the Y chromosome. (ideaoffer.com)
These Y chromosome genes are expressed in one half of all offspring, mainly the males. (ideaoffer.com)
This question arises because genes on the X chromosomes have backup copies to bail them out of trouble in females. (ideaoffer.com)
The further mutated genes would show up on the X chromosome in only half the males because the other half would receive a non-mutated one from their mother. (ideaoffer.com)
Because it has evolved into what researchers refer to as a "supergene"-a cluster of selfish genes on the same chromosome that are inherited together. (eurekalert.org)
The goal of my research is to identify, clone, and characterize the evolution of genes underlying natural adaptations in order to determine the types of genes involved, how many and what types of genetic changes occurred, and the evolutionary history of these changes. (unc.edu)
The high probability of fixation of neutral and mildly deleterious mutations in the mitochondrial genome explains in part its fast rate of evolution, the high observed frequency of mitochondrial disease in relationship to this genome's small size, and may be the underlying reason for the transfer of mitochondrial genes over evolutionary time to the nucleus. (nih.gov)
These Y chromosome sequences now provide new evidence that Neandertals and early modern humans met and exchanged genes before the major out of Africa migration - potentially as early as 370,000 years ago and certainly more than 100,000 years ago. (mpg.de)
Here we model the evolution of proto-chromosomes within protocells as composed of two types of genes: "fast" for gene-level self-replication and "gene" which facilitates protocell-level reproduction. (naturalgenesis.net)
Our results suggest that dimerization can overcome lower-level effects and work in concert with multilevel selection to allow for complementary genes that coexist at the protocell-level but compete at the level of individual gene-level replication. (naturalgenesis.net)
An analysis of the genes of twelve chimpanzees has now demonstrated that the chimpanzee X chromosome plays a very special role in the animal's development. (scienceblog.com)
By sequencing all the genes in twelve chimpanzees from Central Africa, the researchers demonstrated that beneficial variants are accumulated on the X chromosome in particular. (scienceblog.com)
By closely studying all the chimpanzee genes, the researchers found examples of natural selection in the remaining chimpanzee chromosomes all being associated with genes that are important for the immune system, including a gene that gives partial resistance to HIV in humans. (scienceblog.com)
Glacial periods over the past 6 million years promoted the selection of a set of genes responsible for the metabolism and neurohormonal regulation in cold conditions. (chinadaily.com.cn)
If they enhance fitness, acquired genes are likely to be fixed in the population by natural selection. (blogspot.com)
Consequently, conservation of farm animal breeds had been for several reasons, for example, to retain potentially useful genes and gene combinations such as the Booroola fecundity gene in sheep [10], the exploitation of heterosis, and to overcome selection plateaus, in addition to cultural motivations, research, and food security. (scirp.org)
The team identified 1,215 blocks of genes that consistently occur on the same chromosome in the same order across all 32 genomes. (bionity.com)
The scientists found nine whole chromosomes, or chromosome fragments in the mammal ancestor whose order of genes is the same in modern birds' chromosomes. (bionity.com)
This remarkable finding shows the evolutionary stability of the order and orientation of genes on chromosomes over an extended evolutionary timeframe of more than 320 million years," Lewin says. (bionity.com)
How and why males exist in evolutionary overdrive despite carrying essentially the same genes as females has long puzzled scientists. (nbcnews.com)
In flies and humans, thousands of genes made up of DNA are packaged into tiny units called chromosomes. (nbcnews.com)
Many genes are found on the X chromosome, whereas few are associated with the Y chromosome. (nbcnews.com)
For female fruit flies, the X-chromosome genes can come in two flavors called alleles that not only interact with each other but also with other genes. (nbcnews.com)
Having one X means your genes are more open to selection in males," UF researcher Marina Telonis-Scott said in a telephone interview. (nbcnews.com)
While not as prominent a trend, they also found a similar pattern in so-called autosomal genes, which are those found on any chromosome save the sex chromosomes. (nbcnews.com)
Many of the fruit-fly autosomal genes, however, did work in concert with genes located on the X chromosome. (nbcnews.com)

Fig. 1: Phylogeny-scale profiling of scallop sexual systems and sex chromosomes. (nature.com)
Deborah is Senior Honorary Professorial Fellow in the Institute of Evolutionary Biology whose work focuses on the evolution of breeding systems and sex chromosomes. (ed.ac.uk)

Susan is a Royal Society University Research Fellow at the Institute of Evolutionary Biology whose work answers questions on sexual selection, immunity and recombination. (ed.ac.uk)
I should know, because he sponsored the publication of my first article on group selection in the Proceedings of the National Academy of Sciences in 1975 and we have co-authored a number of more recent articles together, including the comprehensive "Rethinking the Theoretical Foundation of Sociobiology" published in the Quarterly Review of Biology in 2007. (evolution-institute.org)
The question of how and why genetic variation arises and is maintained over long periods of time is of key importance to evolutionary biology, population genetics and conservation biology. (lu.se)
Our study clarifies when, how and why this variation arose, and shows that this variation has been maintained over long evolutionary time periods through so-called balanced natural selection", says Erik Svensson, biology professor at Lund University. (lu.se)

Here, we profile eight genomes of the bivalve mollusc family of Pectinidae in a phylogenetic context and show 350 million years sex-chromosome homomorphy, which is the oldest known sex-chromosome homomorphy in the animal kingdom, far exceeding the ages of well-known heteromorphic sex chromosomes such as 130-200 million years in mammals, birds and flies. (nature.com)
Although some reference genomes are available for this clade, few are at the chromosome level, inhibiting high-resolution genomic studies. (biorxiv.org)
Here, we assemble genomes from three members of the genus, the tiger ( Panthera tigris ), the snow leopard ( Panthera uncia ), and the African leopard ( Panthera pardus pardus ), at chromosome or near-chromosome level. (biorxiv.org)
We hope these genomes will aid in further evolutionary and conservation research of this iconic group of mammals. (biorxiv.org)
This is the first time anyone has sequenced the whole genomes of SD chromosomes and therefore been able to make inferences about both the history and the genomic consequences of being a supergene," Presgraves says. (eurekalert.org)
Even higher rates of fixation of deleterious mutations are predicted to occur in the two nonrecombinant genomes in humans, i.e., the Y chromosome and the mitochondrial genome, as a consequence of their lower Ne than autosomes, and the predicted higher rate of fixation of deleterious alleles on the Y may explain the reduced average life span of males vs. females. (nih.gov)
Since then, improvements in molecular techniques have enabled scientists at the Max Planck Institute for Evolutionary Anthropology to determine high quality sequences of the autosomal genomes of several Neandertals, and led to the discovery of an entirely new group of extinct humans, the Denisovans, who were relatives of the Neandertals in Asia. (mpg.de)
we here produced genomes of six birds-of-paradise species here to look into how their sex chromosomes evolve. (nature.com)

While random mutation provides change, the selection is through survival of the fittest. (wikipedia.org)
A Composite of Multiple Signals Distinguishes Causal Variants in Regions of Positive Selection: The human genome contains hundreds of regions whose patterns of genetic variation indicate recent positive natural selection, yet for most the underlying gene and the advantageous mutation remain unknown. (scienceblogs.com)
We develop a mathematical model that considers the potential roles of three evolutionary forces in maintaining XY * females: Y-to-Y * chromosome transitions (mutation), chromosome segregation distortion (meiotic drive), and differential fecundity (selection). (bioone.org)
Through simulation of the evolutionary operations recombination , mutation , and selection new generations of search points are found that show a higher average fitness than their ancestors. (postgresql.org)
It is designed to be used in combination with other crossover and mutation operators (it applies to the best fitted two parental chromosomes only) both in binary and real-valued (evolutionary) GA. Analytical proof of its ability to improve the result is provided for the simplest case of one variable and when elitist selection strategy is used. (lancs.ac.uk)
This theory distinguishes the basic processes of gene mutation and recombination, natural selection , changes in structure and number of chromosomes, and reproductive isolation. (britannica.com)
These differences in natural selection combined with genetic drift and mutation over many generations of separation eventually result in the two populations becoming discrete species. (jove.com)

To what extent are phenotypic differences among human populations driven by natural selection? (scienceblogs.com)
Several lines of evidence argue for an important role of positive selection in shaping human variation and differences among populations. (scienceblogs.com)
Dan MacArthur already posted some of the supplementary figures from Signals of recent positive selection in a worldwide sample of human populations, but he didn't put up one that I thought was really striking. (scienceblogs.com)
However, the researchers used computer simulations to show that the known small size of Neandertal populations may have led to an accumulation of deleterious mutations in their Y chromosomes which would reduce their evolutionary fitness. (mpg.de)
Dr Susan Johnston receives The Balfour Lecture, for her contribution to using genomic information to understand selection and evolution in wild and domesticated populations. (ed.ac.uk)
Her group studies the causes and consequences of recombination rate variation within and between chromosomes, individuals, sexes, populations and species. (ed.ac.uk)
This mechanism may also occur if a group of birds from the original population disperse to another geographic location and undergo natural selection in the new environment, stopping gene flow between the two populations. (jove.com)
In sympatric speciation, natural selection can occur within populations and result in the formation of new species. (jove.com)
Our lab is broadly interested in the evolutionary origin and maintenance of trait diversity within populations. (github.io)
I interpret genetic patterns to ask how populations have spread or contracted, merged or been fragmented and how they have been shaped by natural selection. (qmul.ac.uk)
We therefore attempt to study the early evolution of sex chromosomes using a variety of methods, including characterization of new portions of the sex chromosome in natural populations, and experimental evolution of sex chromosomes in the lab. (lu.se)
This has significance both for conservating species and for the future evolutionary potential of populations to adapt to rapidly changing environments. (lu.se)
Remaining to be tested are how such factors as natural selection, low recombination rate, and genetic drift due to geographic structuring contribute to the formation and maintenance of these clonal complexes in natural bacterial populations ( 3 , 4 ). (cdc.gov)

A few days ago I discussed a new paper which explores the patterns of natural selection in the genome of the X chromosome. (scienceblogs.com)
Population genetic forces have molded the constitution of the human genome over evolutionary time, and some of the most important parameters are the initial frequency of the allele, p, the effective population size, Ne, and the selection coefficient, s. (nih.gov)
Unlike the rest of the autosomal genome, which represents a rich tapestry of thousands of genealogies of any individual's ancestors, Y chromosomes have a peculiar mode of inheritance - they are passed exclusively from father to son. (mpg.de)
This does not apply to the remaining twenty-two chromosomes in the genome, because both males and females have two copies of each of these. (scienceblog.com)
The team obtained the first chromosome-level nonhuman primate genome and developed the phylogenetic relationship to understand the evolutionary process of social systems in Asian colobines, according to a release from the university. (chinadaily.com.cn)
The reconstruction shows that the mammal ancestor had 19 autosomal chromosomes, which control the inheritance of an organism's characteristics outside of those controlled by sex-linked chromosomes, (these are paired in most cells, making 38 in total) plus two sex chromosomes, said Joana Damas, first author on the study and a postdoctoral scientist at the UC Davis Genome Center. (bionity.com)
Also, we compare patterns of evolution to parameters of the tumour microenvironment in order to find out how surrounding factors shape the cancer genome through selection. (lu.se)

Finally I read that the human Y chromosome is much different than the Chimpanzee one, and is the least analogous to its comparable chimpanzee chromosomes. (ideaoffer.com)

If after a bunch of generations, the gene makes it to the finish line, than it appears to the organism to be a possibly successful addition to the gene arsenal and is moved to the X chromosome. (ideaoffer.com)
When the gene proves good enough to move to X chromosome, why is it beneficial for refining mutations to then be exposed by themselves only in one quarter of the offspring, again in males? (ideaoffer.com)
These Y chromosomes provide new insights into the relationships and population histories of archaic and modern humans, including new evidence for ancient gene flow from early modern humans into Neandertals. (mpg.de)
The data show that Neandertals may have benefited from these interactions as the gene flow resulted in the complete replacement of the original Neandertal Y chromosomes by their early modern human counterparts. (mpg.de)
A gene is a subsection of a chromosome which encodes the value of a single parameter being optimized. (postgresql.org)
The OfGT s were found to be located randomly on the 20 O. fragrans chromosomes, and an analysis of gene replication events indicated that the OfGT gene family underwent strong purification selection during the evolutionary process. (biomedcentral.com)
This study made a comprehensive summary of the OfGT gene family, including functions and co-expression patterns in response to salt and other stresses, as well as an evolutionary perspective. (biomedcentral.com)
If that particular gene gives the male a boost in terms of sexual selection, say a gene responsible for fluffier feathers, the gene would be selected for in the game of natural selection over successive generations. (nbcnews.com)
But note that, whereas evolutionary theory makes clear what constitutes a benefit to a gene - replication - it is not at all clear what constitutes a benefit to an individual (let alone a group). (thisviewoflife.com)
We find independent evolutionary strata (stepwise recombination suppression) in several species, with extensive rearrangements, gene losses, and transposable element accumulation. (pacb.com)
RESEARCH analysis of the CTX-Ms that included a representative sam- site in a gene, among-site variation in evolutionary rate was pling of other class A -lactamases. (cdc.gov)

The breeding genetics in this system inherently select against the Y * chromosome such that the frequency of XY * females should decrease rapidly to very low frequencies. (bioone.org)
But there is also an evolutionary genetic aspect to sexual dimorphism we must consider: in Genetics and Analysis of Quantitative Traits the authors note that evolution of sex specific traits is not going to occur fast. (discovermagazine.com)
Professor William (Bill) Hill OBE receives the 2019 Mendel Medal, for his contribution to the understanding of the genetics of quantitative traits and response to selection. (ed.ac.uk)
Professor Deborah Charlesworth receives The Genetics Society Medal, for her contribution to evolutionary and population genetics. (ed.ac.uk)
The research group Genetics of Sex Differences is interested in sexual selection and sexual conflict, the evolution of sexual dimorphism, and sex chromosome evolution. (lu.se)
We are interested in various aspects of the genetics of sex differences, including sexual selection and sexual conflict, the evolution of sexual dimorphism, and sex chromosome evolution. (lu.se)

Welcome to the website of the Theoretical Evolutionary Ecology lab of the Department of Ecology and Evolution at the University of Lausanne. (github.io)
We work in the interface between evolutionary ecology and genomics. (lu.se)

Scientists have long recognized that the exchange of genetic material by crossing over-known as recombination-is vital because it empowers natural selection to eliminate deleterious mutations and enable the spread of beneficial mutations. (eurekalert.org)
But SD is not forward-looking: preventing recombination has led to SD accumulating many more deleterious mutations compared to normal chromosomes. (eurekalert.org)
Without recombination, natural selection can't purge deleterious mutations effectively, so they can accumulate on SD chromosomes," Larracuente says. (eurekalert.org)
There is considerable agreement among evolutionary gerontologists that the amplitude of -s is small for alleles that are Deleterious In Late Life (DILL), and thus DILL traits are effectively neutral and should be fixed in the human population in relationship to Ne and p. (nih.gov)
This was already known regarding deleterious mutations on the X chromosome, e.g. colour blindness as a recessive trait and therefore only occurring in men. (scienceblog.com)
Chunks of DNA are accidentally incorporated into chromosomes creating genetic variation that is neutral, deleterious or, in rare cases, beneficial. (blogspot.com)
Nonrecombining Y chromosomes are expected to degenerate through the progressive accumulation of deleterious mutations. (bioone.org)

However, when complex hybridization scenarios might explain a species' history, or when events are recent enough that coalescent methods cannot be used, haplotype-level information such as is provided by contiguous, chromosome-level assemblies can greatly improve our understanding of these events. (biorxiv.org)
A Cost of Sexual Attractiveness to High-Fitness Females: Adaptive mate choice by females is an important component of sexual selection in many species. (scienceblogs.com)
However, if the Y chromosome fails to initiate the male pathway (referred to as Y * ), XY * females can result, as is the case in several species of South American field mice (genus Akodon ). (bioone.org)
also, adaptation to a diverse selection pressure imposed by climate, nutritional factors, disease, and parasites are natural agents that discern the species and breeds of livestock [8]. (scirp.org)
Called the father of evolutionary botany, he was the first scientist to synthesize artificially a species of plant that was capable of thriving under natural conditions. (britannica.com)
Working with several species of flowering plants, Stebbins and his coworker, Ernest B. Babcock, studied polyploid plants, which are new species of plants that have originated from a spontaneous doubling of the chromosomes of an existing species. (britannica.com)
2. Creationism, born of the denial of the evolution of species through natural selection, was for a long time an almost exclusively American phenomenon. (coe.int)
In lower vertebrates, however, most species display homomorphic sex chromosomes. (bioone.org)
These two groups of species are also among the best demonstration of natural selection and sexual selection. (nature.com)
Genomic analysis of 11 songbird species reveals evolutionary strata and shows their role in reshaping the genomic architecture of songbird sex chromosomes. (nature.com)
Back then I just finished my analyses of sex chromosomes of the other 50 bird species , and he just started his work on bird-of-paradise (he has recently published the results ). (nature.com)
To ornithologists, or to an evolutionary biologist like me who previously knew little about these magnificent species beyond David Attenborough's documentary movies (not surprisingly, there is a species named 'magnificent bird-of-paradise'), it is always the dream species that one would like to work on. (nature.com)
We are interested at how sex chromosomes of bird-of-paradise species evolve. (nature.com)
Interestingly, we found that major changes between the sex chromosomes have all occurred before the songbird species radiation. (nature.com)
Currently, 160 different plasmidic alleles encode scended from a common ancestor that was incorporated in unique TEM -lactamase enzymes (www.lahey.org/Stud- ancient times into the chromosome of the ancestor of Kluy- ies), and all are descended from a single plasmidic ances- vera species through horizontal transfer. (cdc.gov)
Highly differentiated sex chromosomes are common in many species. (lu.se)
We now have a good knowledge base for investigating the colour variation over longer evolutionary time scales among other species of this damselfly genus, which occurs in Europe, Africa, Asia, Australia, North and South America. (lu.se)
These new genetic results help us understand both the evolutionary processes that take place within a species, and what happens over longer evolutionary macroevolutionary time scales of tens of millions of years and across several different species", concludes Erik Svensson. (lu.se)
To achieve our aim, we use methods from species evolution (phylogenetics) to reconstruct the evolutionary history of individual tumours, from its founder cell up to clinical presentation, over treatment periods and at relapse. (lu.se)

I say this because I read there are 4.8 times more mutations there than other chromosomes. (ideaoffer.com)
On the X chromosome, more refining mutations occur. (ideaoffer.com)
So I'm suggesting that there should be a higher amount of mutations than normal on the X chromosome just like Y, but of a less wholesale variety. (ideaoffer.com)
through several different mutations in a specific genetic region on the damselfly's thirteenth chromosome. (lu.se)

The mechanism of sex determination in mammals appears highly conserved: the presence of a Y chromosome triggers the male developmental pathway, whereas the absence of a Y chromosome results in a default female phenotype. (bioone.org)
In contrast to mammals, birds have a ZW sex chromosome system, with two nearly-identical Z chromosomes in males, and one Z and one specific W chromosome in females. (nature.com)

The major evolutionary transitions concept, when properly applied, is useful and clarifying. (edge.org)
It is therefore regrettable that the concept's originators made category mistakes by characterizing two distinctly human traits as outcomes of major evolutionary transitions. (edge.org)
Major Evolutionary Transitions as Bayesian Structure Learning. (naturalgenesis.net)
Complexity of life forms on Earth has increased tremendously, primarily driven by subsequent evolutionary transitions in individuality, a mechanism in which units formerly being capable of independent replication combine to form higher-level evolutionary units. (naturalgenesis.net)
Here we show, building on work connecting replicator dynamics with Bayesian methods, that (i) evolution of a hierarchical population under multilevel selection is equivalent to inference in hierarchical Bayesian models, and (ii) evolutionary transitions in individuality, driven by synergistic fitness interactions, is equivalent hierarchical structures via Bayesian model comparisons. (naturalgenesis.net)
Such convergent transitions in genomic architecture of mating-type determination indicate strong selection favoring linkage of mating-type loci into cosegregating supergenes. (pacb.com)

By detecting the evolutionary trajectories of W-linked sequences, we have found that recombination suppression started in four distinct strata, of which three were conserved across Neognathae. (bvsalud.org)

Humans' niche construction activities have undoubtedly exposed new covariances between genetic variation and fitness during human evolution, but those activities have neither created that variation nor filtered it, so they don't constitute an evolutionary process. (edge.org)
This lack of variation can be explained by the fact that natural selection, which actually eliminates variation, works stronger on the X chromosome than on the remaining chromosomes. (scienceblog.com)
The great colour variation in insects fascinates the general public, and raises questions about the function of colour signals and its evolutionary consequences for partner choice and conflicts between the sexes", says Erik Svensson. (lu.se)

Human evolutionary exceptionalism, however-the tendency to assume that biologically exceptional human traits come into the world through exceptional processes of biological evolution-is a bad habit we need to break. (edge.org)
In response, they have promoted niche construction as a "neglected evolutionary process" that collaborates with natural selection to direct evolution. (edge.org)
Charlesworth, B. The evolution of sex chromosomes. (nature.com)
Jablonka, E. & Lamb, M. J. The evolution of heteromorphic sex chromosomes. (nature.com)
Daish, T. & Grützner, F. Evolution and meiotic organization of heteromorphic sex chromosomes. (nature.com)
The evolution proceeds by change and selection. (wikipedia.org)
A PDE Model for Protocell Evolution and the Origin of Chromosomes via Multilevel Selection. (naturalgenesis.net)
With colleagues, the authors have pursued a parallel approach to view evolution as a learning process, see the Evolutionary Intelligence section. (naturalgenesis.net)
39. Nadachowska-Brzyska K, BURRI RETO , Ellegren H (2019) Footprints of adaptive evolution revealed by whole Z chromosomes haplotypes in flycatchers. (vogelwarte.ch)
She currently works on the evolution of sex chromosomes in guppy fish. (ed.ac.uk)
Previously she studied the evolution of plant mating systems and plant sex chromosomes. (ed.ac.uk)
She particularly focused on selection acting on traits that help plants to avoid inbreeding, and on the comparatively recent evolution of separate males and females - dioecy - in the plant kingdom. (ed.ac.uk)
Genetic Algorithms, first introduced by John Holland in the 1960s, are a subset of evolutionary algorithms inspired by biological evolution. (cash-platform.com)
In his interview, Curry explains why David Hume is the founder of evolutionary psychology, why social constructivists are really just evolutionary psychologists who got carried away, and why nothing about morality makes sense except in the light of evolution. (thisviewoflife.com)
For almost a decade we have had a female-limited X chromosome evolution experiment running in our lab, and during this long-term experiment some interesting and unexpected things popped up. (lu.se)
We started the evolution experiment to investigate intralocus sexual conflict on the X chromosome in Drosophila melanogaster . (lu.se)
However, it became clear almost from the start of the evolution experiment that the FM did not function completely like a normal X chromosome, due in part to the phenotypic markers it carries. (lu.se)
Multiple convergent supergene evolution events in mating-type chromosomes. (pacb.com)
We thus show remarkable convergence in mating-type chromosome evolution, recurrent supergene formation, and repeated evolution of similar phenotypes through different genomic changes. (pacb.com)
Model organisms: conducting experimental evolution, for example on Drosophila fruit flies (with Bill Sherwin in UNSW), I ask if there are flaws or omissions in our current evolutionary models. (qmul.ac.uk)
We reconstructed the history of sex chromosome evolution of bird-of-paradise, and also other songbirds in this work. (nature.com)
purifying selection, which indicates a slow rate of evolution As with the TEMs, numerous alleles encode unique SHV for bla s in the pre-antimicrobial drug era. (cdc.gov)
Sexual antagonism is also thought to be a key factor in the evolution of sex chromosomes. (lu.se)

Modifiers which dampen this effect need to emerge, so that sex-specific selection doesn't have the side effect of dragging the other sex along in terms of trait value (this is a concern when you have traits, such as high testosterone, which might increase fitness in males, but reduce it their daughters). (discovermagazine.com)
To do so we forced the inheritance of the X through females only, to investigate what happens to a number of phenotypic traits when male selection on the X is removed. (lu.se)
The aim of this experiment was to disentangle the effects of the evolved autosomes and the evolved X chromosome, for example if changes on the autosomes tended to cancel out changes on the evolved X. We have already measured a few key phenotypic traits and are now specifically interested in detecting changes in expression data using RNAseq. (lu.se)

The evolutionary consequences of male mate preferences, however, have received relatively little study, especially in the context of sexual conflict, where males often harm their mates. (scienceblogs.com)

We know from studying their autosomal DNA that Neandertals and Denisovans were closely related and that humans living today are their more distant evolutionary cousins. (mpg.de)

As you know the X is "carried" disproportionately by females, as males have only one copy, so it offers up an interesting window into evolutionary dynamics (see The Red Queen for a popular treatment). (scienceblogs.com)
Males have one X chromosome and one Y chromosome, while females have two X chromosomes. (scienceblog.com)
However, a combination of segregation bias of the male and female Y chromosomes during spermatogenesis/oogenesis and increased fecundity in XY * females could account for the observed frequencies of XY * females. (bioone.org)
The reason is simple: aside from the peculiarities on the sex chromosomes males and females are genetically the same. (discovermagazine.com)
Researchers find that males can respond quicker than females to sexual selection, resulting in glitzier garbs like the male peacock's tail feather, which outshows any drab peahen. (nbcnews.com)
In this case, the females have two X chromosomes (XX) and males, XY. (nbcnews.com)
The researchers suggest this uncomplicated (compared with females) genetic pathway allows males to respond at the drop of a hat to the pressures of sexual selection. (nbcnews.com)
Because sex-specific recombination patterns depend on phenotypic, rather than genotypic sex, homomorphic X and Y chromosomes are expected to recombine in sex-reversed females. (bioone.org)

The different copy numbers of Z chromosomes may have contributed to the usually very different phenotypes between sexes. (nature.com)

Female flies transmit SD -infected chromosomes to about 50 percent of their offspring, as expected under Mendel's laws of inheritance. (eurekalert.org)
We were able to enforce matrilineal inheritance by using an X chromosome balancer (FM), which has multiple inversions so it cannot recombine with the selected X but should still function as a normal X chromosome. (lu.se)

It is difficult to study these processes in old, already highly heteromorphic, sex chromosomes. (lu.se)

Execution Analyses to identify evolutionary first principles that make cancer cells grow, spread, and survive microenvironmental challenges. (lu.se)

They also provide an explanation of previous studies in which it was observed that the X chromosome behaved strangely during the speciation process of humans and chimpanzees, in that it was considerably less variable than the remaining chromosomes. (scienceblog.com)

For years, Niche Construction theorists have argued that standard evolutionary theory cannot account for such interactions between humans' culturally mediated environmental effects and natural selection. (edge.org)
Surprisingly, this interbreeding resulted in the replacement of the original Neandertal Y chromosomes with those of early modern humans, a pattern similar to what has been seen for Neandertal mitochondrial DNA in an earlier study. (mpg.de)
The researchers found that about a third of all the changes that have taken place on the X chromosome since humans and chimpanzees diverged approximately four to six million years ago have been beneficial for the chimpanzee. (scienceblog.com)

The nonrecombining female-limited W chromosome is predicted to experience unique evolutionary processes. (bvsalud.org)
We are looking for a student with bioinformatic skills, who also have good understanding and interest in evolutionary processes. (lu.se)

Contrary to classic theory prediction, sex-chromosome homomorphy is prevalent in the animal kingdom but it is unclear how ancient homomorphic sex chromosomes avoid chromosome-scale degeneration. (nature.com)
Molluscs constitute the second largest, Precambrian-originated animal phylum and have ancient, uncharacterized homomorphic sex chromosomes. (nature.com)
On the basis of these findings, we propose an evolutionary model for the long-term preservation of homomorphic sex chromosomes. (nature.com)

The researchers also calculated that the most recent common ancestor of Neandertal and modern human Y chromosomes lived around 370,000 years ago, much more recently than previously thought. (mpg.de)
Evolutionists generally refer to an unknown evolutionary ancestor to explain ancestral states. (icr.org)

However, little information is available on the evolutionary role of combinations generated by inversions located in homologous and non-homologous chromosomes. (datadryad.org)
Thus, it seems that for each pair of homologous chromosomes inversions no deviation from randomness was detected. (datadryad.org)
Finally, no linkage disequilibrium was observed between inversions located in different chromosomes of the karyotype. (datadryad.org)
For all these reasons it can be assumed that, at the cytological level, the individual inversions rather than their combinations in different chromosomes are the main target of selection. (datadryad.org)

For this objective, we have studied the inversion composition of homologous and non-homologous chromosomes from a D. subobscura sample collected in a well-studied population, Mount Avala (Serbia). (datadryad.org)
In addition, a new environmental selection based on a reference population is designed to keep diversity of the population in each generation and an infill criterion for handling the trade-off between convergence and model uncertainty is proposed for re-evaluation. (springer.com)

That is, what unique and novel insights about morality does an evolutionary approach provide? (thisviewoflife.com)
Human cancer cells: I work with Trevor Graham (Barts Cancer Institute) using experiments on cancer cell lines to ask if we can identify strategies to retard resistance to chemotherapy, by exploiting evolutionary insights. (qmul.ac.uk)

This allowed them to reconstruct the Y chromosome sequences of these individuals, which would not have been possible using conventional approaches. (mpg.de)

In this study, the researchers identified three male Neandertals and two Denisovans that were potentially suitable for DNA analysis, and developed an approach to fish out human Y chromosome molecules from the large amounts of microbial DNA that typically contaminate ancient bones and teeth. (mpg.de)
Scientists have no fossil molecules, and thus they cannot go back into deep evolutionary time and analyze the hypothetical pre-hemoglobin that supposedly existed. (icr.org)

Due to their lack of recombination, SD chromosomes have begun to show signs of evolutionary degeneration. (eurekalert.org)

Over the past three billion years, natural selection has yielded several pivotal innovations in how genetic information gets assembled, packaged, and transmitted across generations. (edge.org)
To be sure, human language, as the only communication system with unlimited expressive potential that natural selection ever devised, is biologically exceptional. (edge.org)
However, this inference assumed that all copies of the 9-repeat allele were identical by descent and that the geographic distribution of this allele had not been influenced by natural selection. (scienceblogs.com)
The aim of this research is to ascertain whether these combinations are also a target for natural selection. (datadryad.org)
This process is called natural selection. (scienceblog.com)
On the other hand, the males only have one X chromosome and it is expressed immediately, thus enabling natural selection to 'catch sight' of it. (scienceblog.com)
In the ever-evolving landscape of artificial intelligence, one approach stands out for its ability to harness the power of natural selection and optimization: Genetic Algorithms (GAs). (cash-platform.com)
These algorithms simulate the process of natural selection to find approximate solutions to optimization and search problems. (cash-platform.com)
Dr Curry is Departmental Lecturer at the University of Oxford's Institute of Cognitive and Evolutionary Anthropology, as well as Research Associate at the London School of Economics' Centre for Philosophy of Natural and Social Science. (thisviewoflife.com)
natural selection cannot work any other way. (thisviewoflife.com)
These rare events should generate bursts of new Y haplotypes, which will be quickly sorted out by natural or sexual selection. (bioone.org)
Two groups of birds, Darwin's finches and Birds-of-Paradise are historically and respectively associated with the discoverers of the rules of natural selection:Charles Darwin and Alfred Wallace. (nature.com)
Wallace may have been overshadowed by Darwin on his independent conception of natural selection. (nature.com)

Contributors review multiple examples of sexual antagonism (e.g., parental care and mating rate), its genetic basis, the various and sometimes dramatic ways that it is manifested (e.g., infanticide and copulatory wounding), and its evolutionary impacts, especially on male-female coevolution and reproductive isolation. (cshlpress.com)

Y chromosomes, and also the maternally-inherited mitochondrial DNA, have been extremely valuable for studying human history. (mpg.de)

A collection of chromosomes that evolves over generations. (cash-platform.com)
Though under cover, the recessive allele kind of hitches a ride on the X chromosome and can be passed on to future generations. (nbcnews.com)

Recombination suppression between sex chromosomes, usually through chromosome inversion, is very critical for maintaining the sex. (nature.com)

The flies were identical genetically, except for their sex chromosomes . (nbcnews.com)

Their second category mistake was to hold up human language as the outcome of major evolutionary transition. (edge.org)
Fig. 6: Evolutionary model for homomorphy maintenance and heteromorphy transition of sex chromosome. (nature.com)
Did human culture arise through an evolutionary transition in individuality (ETI)? (naturalgenesis.net)
Did Human Culture Emerge in a Cultural Evolutionary Transition in Individuality? (naturalgenesis.net)

Human evolutionary exceptionalism has sown misunderstanding in every area it has touched. (edge.org)
By comparing the archaic human Y chromosomes to each other and to the Y chromosomes of people living today, the team found that Neandertal and modern human Y chromosomes are more similar to one another than they are to Denisovan Y chromosomes. (mpg.de)
The new results make it probable that corresponding activity takes place in the human X chromosome. (scienceblog.com)
What can evolutionary approaches tell us about human moral systems that other approaches cannot tell us? (thisviewoflife.com)
Human Homosexuality: A Paradigmatic Arena for Sexually Antagonistic Selection? (cshlpress.com)

New research on fruit flies, detailed online last week in the journal Proceedings of the National Academy of Sciences, finds males have fewer genetic obstacles to prevent them from responding quickly to selection pressures in their environments. (nbcnews.com)

An international research team led by Martin Petr and Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has determined Y chromosome sequences of three Neandertals and two Denisovans. (mpg.de)
Difficulties in assembling W chromosome sequences have hindered the identification of duck W-linked sequences and their evolutionary footprint. (bvsalud.org)

At first, the complete replacement of both Y chromosomes and mtDNA of early Neandertals was puzzling, as such replacement events are quite unlikely to occur by chance alone. (mpg.de)
Hemoglobins occur sporadically among the invertebrate phyla in no obvious [evolutionary branching] pattern. (icr.org)

We developed a method, Composite of Multiple Signals (CMS), that combines tests for multiple signals of selection and increases resolution by up to 100-fold. (scienceblogs.com)
The composite evolutionary tree. (icr.org)

In this corner, multilevel selection theory (MLST), a configuration of ideas that began with Darwin and has maintained a degree of continuity, in addition to a degree of change, up to the present. (evolution-institute.org)

Groillas are highly polygynous, and there is a great deal of male-male competition, therefore driving sexual selection. (discovermagazine.com)
Called sexual selection, the result is typically a showy male and a plain-Jane female. (nbcnews.com)
This volume includes discussion of the evolutionary origins of sexual conflict and its relationship to other evolutionary forces (e.g., sexual selection). (cshlpress.com)
Thus there is usually extreme sexual selection on male bird-of-paradise. (nature.com)

Anatomy63

Organisms7

Diseases22

Chemicals and Drugs28

Analytical, Diagnostic and Therapeutic Techniques and Equipment30

Psychiatry and Psychology2

Phenomena and Processes175

Disciplines and Occupations3

Technology, Industry, Agriculture1

Information Science6

Health Care4

Genes32

Systems and sex chromosomes2

Biology4

Genomes8

Mutation7

Populations13

Genome7

Chimpanzee chromosomes1

Gene11

Genetics6

Ecology2

Deleterious7

Species19

Mutations4

Mammals2

Transitions6

Trajectories1

Variation3

Evolution23

Traits3

Consequences1

Autosomal1

Females8

Sexes1

Inheritance2

Heteromorphic1

Analyses1

Speciation1

Humans3

Processes2

Homomorphic3

Ancestor2

Inversions4

Population2

Insights2

Reconstruct1

Molecules2

Degeneration1

Natural13

Reproductive isolation1

Mitochondrial1

Generations2

Inversion1

Genetically1

Transition4

Human5

Flies1

Sequences2

Occur2

Composite2

Multilevel selection1

Sexual selection4