Questions tagged [molecular-evolution]

The study of evolutionary mechanisms in operation at the molecular scale, primarily DNA, RNA, and proteins.

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What causes the elongation of Genome down the evolutionary time line

Theory of natural evolution says that complex life forms arose from simpler ones e.g. starting from Eubacteria to modern day multicellular eukaryotes. {If we try to reduce these changes happening at ...
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What are the methods for detecting anagenetic versus cladogenetic change?

I'm new to the study of phylogenetics and am wondering if there are ways of identifying evolutionary changes that associate with cladogenetic events versus those that arise via anagenesis.
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How valid is Schwartz's criticism of molecular phylogenetics?

A proponent of the human-orangutan clade, Jeffrey Schwartz argues, in this paper [1], that molecular phylogenetics is largely based on a baseless assumption. To sum up, according to him: this type of ...
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Increase rate of change in coding regions?

If a sequence is under selection will it acquire more changes over time because of faster fixation than if changes were neutral? Is this true or am I missing something?
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Can anyone help me with these Biology evolutionary properties homework questions? [closed]

my teacher assigned these worksheet questions, they are ungraded, but he said something might come up on the test really similar to this so I really want to get all of them right. I am pretty ...
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Why did translation develop a specific codon for initiation?

The translation of mRNA is initiated by a specific methionine-accepting tRNA at a specific initiation codon, usually AUG (complementary to the tRNA anticodon). However translation at suitable (albeit ...
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Is there a software simulator for monomeric formation, a la Miller-Urey?

At the moment, does any widely-available software exist for small-scale, programmable simulation of monomeric formation in specific conditions? Could one, for instance, recreate the Miller-Urey ...
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What is the evolutionary relationship between heme, chlorophyll and other tetrapyrroles?

As a non-biologist, I have searched the Internet and found dozens of papers discussing the similarity between the structures of heme and chlorophyll molecules, but I could not find any discussion of ...
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What created the first ribosome

If a ribosome is made of protein, yet is used in protein sysnthesis, what created the first ribosome? What created the ribosomal RNA?
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When we talk of functional macromolecules (e.g. proteins as enzymes, hormones, receptors, antibodies etc), towards what are they evolving?�

Actually this is a question which is given in a book and to be honest,it has baffled me.I'm not so much well versed with molecular evolution so my guess would be,say some sort of enzyme which could ...
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Does low gravity exposure to early stages of human fetus have potential to unloc unused genetic information from earlier stages of evolution?

The title seems quite self explanatory but let me elaborate. New mutations do take a very long time and many generations to occure in the genetic code. But our genetic code already holds all the ...
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Mutation rate and Evolutionary rate?

What is the difference between then?I have read some jobs that describes analysis about mutations rates and another ones with evolutionary rates.I want to know the diferrence between then.
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Do ring species exist?

In trying to understand evolution better, I have been looking at examples of speciation, and have thus come across the topic of ring species. I have tried to find concrete examples of how these work, ...
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Can I simulate a previous and next sequence of my fasta files?

I have fasta sequences of a virus protein that had suffered a mutation in 2008 and this mutant had increase it fitness when compared to wild strain (according to literature).I want to simulate if my ...
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How would inserting a nonfunctional protein impact fitness of an organism?

Producing proteins costs energy, and producing longer proteins costs more energy than shorter proteins. Producing proteins which have no function, would therefore presumably negatively impact the ...
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Can I make an population genetic analysis from incomplete protein?

I have an dataset of fasta sequences. This proteins are not complete (My sequences have 700 nucleotides,while complete sequences have 1725 nucleotides)I would like to know if i can make an population ...
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Coacervater were more like Viruses or Cells?

The answer considers them as first formed living cells as they were precursor of life. But they had no lipid bilayer nor any cellular organization, shouldnt they be more like Viruses ,or like Prions ...
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Is transition more common than transversion during the evolution of duplicated genes?

Transitions are base mutations of purine to purine (A <-> G) or pyrimidine to pyrimidine (C <-> T). Transversions are purine to pyrimidine or vice versa (A <-> C, A <-> T, G <-> C, G &...
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Are there any open phylogenetic projects that don't require coding to make a contribution

I am stay at home learner, not pursuing education formal education and currently doing a part time job. I've however completed masters in biotechnology and I'm studying to pursue PhD in molecular ...
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Is there recent info about the hypothetical ancient two-codon genetic code?

Here is the latest I have found. link This is the basic idea: Evolution does not look ahead and make plans. It would not create a system of mRNA with giant ribosomes to create proteins, until ...
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Is there a specific terms to describe variant of existing genes in bacteria?

I have a question regarding a specific term that describes the variant of existing genes. I am analyzing whole-genome sequencing of a bacterial isolate. I found there are a large number of genes that ...
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What causes the complementary copy of an RNA molecule to separate?

I have recently read an article which explains that, in the RNA World hypothesis, an RNA molecule gets 'scanned' by nucleic acid, catalysed by a different specifically-folded RNA molecule, to arrange ...
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Creating ideal conditions for life

Suppose some scientists built a large vat, sterilised it and filled it with distilled water. Then they start dissolving compounds into the water such as amino acids or what ever they deem conducive to ...
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What is the point of inter-species specific quorum-sensing?

So apparently, according to this TED video, there is a kind of quorum sensing involving a universal, inter-species specific molecule that all bacteria secrete. Is there any evidence of bacteria being ...
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Are molecular machines encoded in the DNA?

I don't know much, if anything, about molecular biology. I watched the "inner life of the cell" on Youtube which triggered my curiosity about how these molecular machines came to be. My simple ...
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Is there any evidence that supports glycolysis in mitochondria or chloroplasts?

Glycolysis is known to be a part of cellular metabolism undergone by both eukaryotic and prokaryotic cells, whether under aerobic or anaerobic conditions. As the endosymbiotic theory states that ...
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How to attain a deep conceptual grasp of key atomic/molecular/genetic/ notions? [closed]

It's a total noob question, I know. I'm a layperson trying to come to grips with basic scientific terminology. I always face a conceptual hurdle in trying to understand micro-talk. The way I'm using ...
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Proteins in different organisms

I know that DNA is universal meaning that all organisms have the same 4 base pairs and also that the same codons code for the same amino acid in all organisms. What I am wondering is that say humans ...
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computing relative synonymous codon usage from a coding sequence alignment while accounting for phylogenetic inertia?

I would like to compute the relative synonymous codon usage (RSCU) from coding sequence alignments. But since the coding sequences from an alignment are not independent realization, the statistics (...
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Have we ever observed fertile offspring with a different number of chromosomes than the parents?

Chimpanzees are supposedly the closest relative of humans from a DNA perspective, they are both diploid, and they both undergo meiosis. However, chimpanzees have 24 chromosome pairs while humans have ...
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What are some examples of non-homologous sequences having similar functions?

I am trying to find some proteins that are non-homologous but functionally similar. However, I cannot seem to find concrete examples. Can someone please point out any resources or provide examples?
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How did genome duplication in jawed vertebrates allow gene specialization?

I am currently reading from Chapter 15 in Principles of Life, 2nd Edition: Many gene duplications affect only one or a few genes at a time, but in some cases entire genomes may be duplicated. When ...
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444 views

How to interpret McDonald-Kreitman test results?

It is easy to get the numbers right and calculate neutrality index. It is easy to memorize "equals", "greater", "lesser", etc. At least on the exams, when certain level of simplicity is assumed. But ...
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Is genetic purging based on random shuffling of the genes of an individual or is it more intentional way of removing deleterious recessive alleles?

Inbreeding depression may be reduced by selection against deleterious alleles, which eliminates, or purges, them from the population. I have two questions: Is genetic purging based on random ...
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Pros and cons of amino acid structure vs DNA sequences for evolutionary comparison [closed]

This is an analysis question for a lab on the amino acid differences in beta globin amongst different primates, and using such differences to construct a cladogram and infer evolutionary relationships ...
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How to choose the most appropriate measure of genetic distance

I am conducting a phylogeography study of a fish species and am trying to construct a phylogenetic tree to describe population structure and ancestry. I have constructed trees using various measures ...
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New evidence about the beginning of life? [closed]

The cover story of the August Scientific American is about new evidence suggesting "volcanic pools" as the location for "first life" as opposed to deep sea smokers like "The Lost City". I was under ...
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Differential Gene Expression

I have a matrix two gene expression datasets, one from 10 normal individuals and ten from diseased individuals, which are normalised log fold change values--, i.e., already processed. My question is:...
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Evolution of autophagy and apoptosis

Autophagy and apoptosis are both necessary for survival of a multicellular organism. I have some information on evolution of autophagy and apoptosis. However, the key difference between the pathways ...
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Text Book Recommendation: Organic Evolution

I was wondering if anyone could point me in the direction of any text books on organic evolution? I have recently become interested in the subject and would like to know more. I think an undergrad ...
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Polymorphism in number of chromosomes?

The answer to this question, saying that Down Syndrome - a trisomy of human chromosome 21 - is caused by de novo mutation (rather than resulting from standing variation) made me think about ...
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Does science have an explanation of how the first “common ancestor” formed in evolution? [closed]

I always have this question on my mind and I need a better explanation on this. Does Charles Darwin's theory explain it or are there any other theories which explain it better than Charles Darwin's ...
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Is it possible to have a mechanism to use carbon dioxide as a source of oxygen in human body?

Is it possible to seperate O2 from CO2 and use it for energy In Human? Why Plants and not Humans can do it?
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Why has life evolved around oxygen? [closed]

Why has life evolved around oxygen? Many lifeforms require oxygen to breakdown bio-molecules and release energy. I think there are two possibilities: Reactions with oxygen tend to release more energy,...
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Why do (almost) all energy carriers contain adenine?

Unlike this question which is specific to just ATP, this one includes all energy carriers. When thinking of common energy carrying molecules, I can think of Adenosine triphosphate (ATP), Nicotinamide ...
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is there any theory about why life evolved to have DNA with 4 different bases and not 6 or other number like in organisms created with artificial DNA? [duplicate]

If organisms can carry DNA with 6 bases which supposedly stores increased genetic information, why living organisms evolved to have DNA made of 4 bases and not 6 or other number? is there any theory ...
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CRISPR/Cas9: What are the main differences between sgRNA and the Cr:TracrRNA ?

So from what I understand, in gene editing, the CRISPR vector expresses a small RNA sequence comprised of a small guide-RNA that is complementary to your target sequence. The sgRNA comprises a 20 Bp ...
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Source for an upper bound in the number of genes based on mutation rates

So I've found myself referring in an answer once again to the idea that complexity (insofar as it's a quantity for which "number of genes" is a proxy) has an upper bound, limited by Muller's ratchet-...
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phylogenetics and substitution ratios for positive selection [closed]

So very new to phylogenetics!. I've been scrambling and reading so much to get this done!!. I would like to see if one or more of the sequences I have (from a gene family) are under positive ...