Questions tagged [molecular-evolution]
The study of evolutionary mechanisms in operation at the molecular scale, primarily DNA, RNA, and proteins.
172
questions
-1
votes
1
answer
60
views
Does Mitochondrial Eve existence suggest genetic fitness, and what evolutionary developments map to her time period?
I am not sure of the size of the population at the time of Mitochondrial Eve, but I assume it must have been reasonably large. It seems to me that without bias, each female at that time should have ...
0
votes
1
answer
38
views
How do we logically infer large time scales using Molecular Clocks?
If molecular clocks are uses in genetics to determine the mutation rate of genes to estimate times speciation occurred between two or more life forms, are there genes that have mutation rates that we ...
0
votes
0
answers
38
views
How do we know how long speciation occured? [duplicate]
Just as we use radiometric dating to age rocks, what is the method used to age how long ago speciation occurred in genetics?
-2
votes
1
answer
120
views
Why don't animal cells have both mitochondria and chloroplasts? [closed]
Ancestral eukaryotes had both mitochondria and chloroplasts, why do animal cells only have mitochondria. Why did evolution allow animal cells to give up such a great circle of energy? Where the waste ...
-2
votes
1
answer
67
views
When a dog sniffs up organic material that contains DNA, is it possible his genome incorporates it? [closed]
I'm not kidding. Was just watching my German Shepherd sniffing away at a new Amazon box.
...realized she sniffs vast array of DNA from organic material when on a walk: millions of mammalian, plant, ...
0
votes
0
answers
75
views
When and how did the Embecovirus acquire hemagglutinin esterase?
The Embecovirus is different from the rest of Betacoronavirus by possessing an additional protein, a hemagglutinin esterase (HE).
There are known similarities between the HE's of different viruses (...
2
votes
2
answers
178
views
Why isn't speciation a negative feedback loop?
To rephrase my question more articulately:
Speciation begins when two groups within a species starts to become reproductively isolated, and is complete when the two groups can't interbreed (for the ...
3
votes
0
answers
215
views
Why does mitochondrial DNA have a high mutation rate, even though the mitochondrial function is highly conserved?
My understanding is that genes that are functionally important are more highly conserved. The DNA coding for ribosomal RNA is one example of that. I was surprised to find out that mitochondrial DNA ...
1
vote
1
answer
36
views
What is the mathematical relationship between selection coefficient and dN/dS
dN/dS is often used as a measure of the intensity of selective pressure on a mutation or gene, but I'm curious about how it can be written as a function of the selection coefficient. I'm specifically ...
1
vote
1
answer
105
views
can a cell evolve into a different species in the lab?
A friend of mine does not believe in evolution. He claimed that we can not as humans observe a single cell evolving into a different cell. Is that possible to be observed in the lab?
Thanks in advance....
1
vote
1
answer
42
views
Do TADs derive from operons?
TADs (Topologically associated domains) are DNA sequences in the eukaryotes genome (except plants) that are between two sequences named "Insulator". The genes in TAD just are affected by ...
0
votes
0
answers
31
views
Which genes/proteins constitute the core components of the circadian clock?
What the title says.
For instance in Drosophila melanogaster and Mus musculus (see Patke et al. 2020) the CLOCK, CYCLE/BMAL, CRYPTOCHROME, PERIOD setup seems to be conserved. But other components also ...
1
vote
1
answer
80
views
Do mutations that cause the loss of a complex trait occur more often than mutations causing gain of a complex traits?
The Wiki entry on the evolution of biological complexity states that "[m]utations causing loss of a complex trait occur more often than mutations causing gain of a complex trait". There is ...
1
vote
1
answer
48
views
Is there an published method for removing the effect of isolation by distance from genetic distances?
Isolation by distance is the phenomena that (even partial) reproductive isolation due to geographical distance between reproductive populations will result in greater genetic distance between those ...
0
votes
1
answer
88
views
Reasons for the existence of symporters and antiporters
I'm wondering what is an evolutionary adaptation to the evolution of symporters and antiporters instead of just uniporters.
Antiporters might help preserve electrical neutrality by pumping in/out an ...
1
vote
1
answer
322
views
Defining "species" (Are species an emergent property or an ensemble of quantitative differences?)
Interbreeding
Defining species by the criteria of not being able to breed is problematic:
The concept loses its meaning in phylogenetic prospective, since closely related species were able to breed ...
4
votes
1
answer
78
views
Caloric Mimicry
I was thinking about natural "zero calorie" sweetners and how these compounds could come to be via evolution. I was specifically thinking about monk fruit. While artificial selection likely ...
1
vote
2
answers
1k
views
Does the Miller-Urey experiment explain the origin of life?
According to the Miller-Urey experiment, the early earth atmosphere could have supported the formation of amino acids - and the experiment is hailed as being important in the explanation for the ...
3
votes
1
answer
55
views
What are the relative roles of coding DNA versus regulatory DNA thought to be in evolution?
Intuitively, once you have the idea that some DNA is responsible for turning on and off the DNA that codes for proteins, it's possible to imagine that the regulatory DNA is actually the most important ...
1
vote
1
answer
55
views
Population Genetics Using WGS: How do I know when I have enough individuals?
I am having a difficult time finding information about a minimum threshold for number of individuals to use in wgs pop gen analyses. Are there software or formulas/theory available to determine what ...
0
votes
1
answer
56
views
Common ancestry of our cells to the first unicellular cell
If we start the chapter of life with low fidelity self replicating RNAs forming exactly identical copies of themselves, which then later evolved to form the first primordial basic cells which further ...
4
votes
1
answer
2k
views
Why is DNA replication so much faster in prokaryotes than eukaryotes?
There are many statements to be found on the internet of the sort:
“DNA replication occurs at elongation rates of about 500 nucleotides
per second in bacteria and about 50 nucleotides per second in
...
0
votes
1
answer
288
views
gene mutation occurs on two strands of DNA or just one strand?
Suppose we have one strand with 3'-AAA-5' and the other strand is 5'-TTT-3'.
So when point mutation occurs, does it happen to two strands at the same time? e.g. 3'-AAA-5' becomes 3'-AGA-5' and 5'-TTT-...
6
votes
2
answers
265
views
What is neutral theory of evolution?
The question is not about the very basics, but more about where the line separating the neutral theory from the rest of population genetics lies.
One often reads/hears claims that "the findings ...
2
votes
2
answers
242
views
What are the considerations for studying population genetics of bacterial pan-genomes?
I am beginning to work in the field of human gut microbiome, and wondering how (and if) the concepts of population genetics could be applied there.
Considering the competition between the species ...
0
votes
1
answer
96
views
What is the impact of selection on orthologous and paralogous genes? How would this impact differ in different regions of protein coding genes?
Since paralogs increase the size of the genome and provide more opportunity for the evolution of novel characteristics, would they be more prone to selection?
6
votes
1
answer
140
views
Why are Chromosome Territories important?
Chromosomes occupy discrete regions of the nucleus, referred to as 'Chromosome Territories'. This spatial organization is emerging as a crucial aspect of gene regulation and genome stability in health ...
0
votes
1
answer
570
views
Why is selection less effective in small populations than in larger?
I can understand that the genetic drift has a higher impact on smaller populations, but what does it mean for the selection to be less effective in small populations than higher?
0
votes
0
answers
18
views
Definition of "genomic adaptation"
I have encountered the term genomic adaptation in some literature (for example Sikkink et al. 2017). I am struggling to parse the term, and I have not been able to ...
1
vote
1
answer
113
views
Questions regarding serial passage of virus through animals arising from the paper The proximal origin of SARS-CoV-2
In this answer on bioinformatics.stackexchange.com to the question inquiring about the validity of the paper Kristian G. Andersen et al, The proximal origin of SARS-CoV-2, the author asserts the ...
0
votes
1
answer
44
views
Are the alleles that code for the same phenotype all the same exact sequence?
The idea that you can be homozygous for a gene means that there are limited options or alleles , correct ?
My question is, if the mom has the allele b which codes for a blue eye, and the dad has an ...
1
vote
1
answer
86
views
How do we formulate the mutational load for "junk DNA"?
Question(s)
Based on Joe Felsenstein's textbook, I was trying to formulate the mutational load for the majority of eukaryotic genomes that are junk DNA ($L_{most\_of\_genome}$). (See background ...
1
vote
2
answers
613
views
Why is glycerol the backbone of fat?
Fats are fatty acids joined onto the backbone of a glyercol (propane-1,2,3-triol).
Why was glycerol seemingly chosen by nature to be the backbone of fats? Why can't it have been a butane -1,2,3,4- ...
0
votes
1
answer
28
views
Relationship of RNA-binding proteins to peptidyl-prolyl cis-trans isomerase [closed]
I am studying a Plasmodium gene, known to encode an RNA-binding protein. However a BLAST search brings up mainly peptidyl-prolyl cis-trans isomerases from other species. Why would this be so?
16
votes
1
answer
9k
views
How many times has SARS-CoV-2 mutated?
According to
Coronavirus has mutated at least once
The novel coronavirus that has infected thousands of people across the
world may have mutated at least once — meaning there may be two
...
0
votes
0
answers
85
views
Why are probionts not considered cellular life? [duplicate]
I am currently studying Prescott's Microbiology, 10th edition, by Willey, Sherwood, and Woolverton. Chapter 1.2 Microbes Have Evolved and Diversified for Billions of Years presents the following ...
-2
votes
4
answers
254
views
Why doesn't evolution converge on perfection? [duplicate]
I got to know about an organism called "Tardigrade(water bear)" which is an extremely hardy organism and can survive in most conditions.
My question is that if the aim of life in general is to ...
1
vote
1
answer
151
views
What are the implications/predictions of the selfish gene theory?
Are there any testable predictions or implications of the selfish gene theory? Or it is just interesting interpretation of the observations/experimental data? If this theory is not falsifiable and ...
1
vote
1
answer
65
views
What is known about major events of pre-LUCA evolution?
All organisms share many common biochemical features (including 20 amino acid genetic code) and are believed to have a common ancestor (so-called LUCA). According to wikipedia article, this common ...
0
votes
0
answers
23
views
Effect on gene loss because of compartmentalisation of plastids/mitochondria/endosymbiont?
Considering the transfer of genes during endosymbiosis a gene transfer event (at least fundamentally, even if it's a special case), how does the fact that in this case the genes are inside a ...
1
vote
3
answers
224
views
Is evolution a means to an end?
In "The Red Queen", Matt Ridley frequently argues that evolution is a means to an end, without providing much explanation for such a big statement.
Is this a fact in biology? Do species mutate their ...
1
vote
1
answer
50
views
What causes the elongation of Genome down the evolutionary time line [closed]
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 ...
0
votes
0
answers
55
views
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.
1
vote
1
answer
81
views
Why is the GULO pseudo gene expressed in humans?
The GULO pseudo gene is being expressed in humans according to Genecards.
Why is this still taking place after tens of millions of years since then gene lost the capacity to encode for a functional ...
2
votes
0
answers
87
views
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 ...
1
vote
1
answer
30
views
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?
-2
votes
1
answer
134
views
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 ...
3
votes
1
answer
338
views
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 ...
3
votes
2
answers
727
views
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 ...
0
votes
1
answer
151
views
What created the first ribosome [duplicate]
If a ribosome is made of protein, yet is used in protein sysnthesis, what created the first ribosome?
What created the ribosomal RNA?