Changes in the heritable attributes of populations of organisms over time. The mechanisms of evolution are mutation, migration, drift, and selection.

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What did cyanobacteria gain from photosynthesis?

As far as I understand, cyanobacteria began performing photosynthesis long before plant cells as we know them arrived on the scene. But cyanobacteria do not seem to use polysaccharides in the same way ...
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5answers
2k views

How can homosexuality evolve despite natural selection?

I would imagine that the answer to this question would be population control, especially since even if one sibling is homosexual this does not necessarily mean that the other siblings will be too.
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1answer
286 views

Examples of Vestigial Genes

I consider the existence of a broken GULO gene in humans to be the clearest evidence for human evolution - just what else is it doing there otherwise? Are there any other examples of vestigial genes ...
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0answers
9 views

Do bears generally have sesamoid bones in their fore and hind feet?

I can't seem to find any information specifically (that shows photographic evidence) of whether bears (of any kind) have sesamoid bones in their feet. And whenever I read information that says that ...
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40 views

Why females evolved to be physically weaker than males? [duplicate]

Why have male-female diverged in relationship to strength? What is the evolutionary advantage for this?
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1answer
3k views

Why are men stronger than women?

What are the evolutionary explanations for why women are physically weaker than men (on average), and is this difference adaptive? See figure one here. I suppose that something puts pressure on men ...
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Effective population size of a metapopulation structured on a grid

Scenario Consider a rectangular metapopulation consisting of $x \cdot y$ demes, where $x$ is the number of deme horizontally and $y$ is the number of demes vertically. The population size per deme is ...
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11 views

Effective population size of a continuously spread population

Is there any model to calculate (theoretical predictions) the effective population size of a continuously spread population? Imagine for example a population spread over an infinite 2D landscape. ...
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2answers
156 views

Components of the concept of Developmental Noise?

Developmental noise is a concept that correspond to the amount of possible phenotypic variance of a given genotype in a given environment. Intrinsic noise (aka Cellular noise) is a component of ...
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213 views

Randomness in living systems

The point of my question is not to talk about events that are uncontrolled by living organisms. My question is about controlled randomness, or I'd like to say adaptive random process. Process that are ...
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1answer
62 views

Why do many people seem to prefer unhealthy compared to healthy foods?

I don't have any concrete statistics on this but many of us seem to love the taste of food that is unhealthy for us. Over the centuries, wouldn't it have been a non negligible advantage to those who ...
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1answer
64 views

Are there evolutionary advantages for the bee sting to kill the bee?

The question title says it all: are there advantages for the sting of a bee to kill the bee? It seems to me getting rid of this would have only advantages, and might've been selected for if a mutation ...
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1answer
42 views

Which of these versions of allopatric speciation is correct? [closed]

I'm confused with the illustrations of allopatric speciation. Here are two diagrams- Which one of them is correct and why? According to wikipedia the second figure is correct but I'd like to know ...
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2answers
118 views

Does evolution head to some optimum? [closed]

Currently we have many species which are "good enough" for current environment, some species emerge, another die. So let's say that they could be close to some local optima. Does the evolution head to ...
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2answers
57 views

Would it be possible to eat things from another planet [closed]

Although at first glance my question is perhaps better suited for a space exploration or sci-fi forum I looked and felt this forum was more appropriate. What makes plants and animals edible and ...
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2answers
709 views

Can parents' learned traits be transmitted genetically?

I am wondering whether a behavioral trait (e.g. fear or stress experienced in the lifetime of the parent) can be transmitted genetically to its offspring? I understand that a behavioral tendency for ...
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0answers
20 views

Has anything evolved to prey on endoparasites?

Is there any organism which lives within a host but gains nutrition not from host cells/materials but by preying on the host's endoparasites? If not, what barriers might exist to the evolution of ...
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5answers
362 views

Why have parasites not evolved to be harmless?

I have yet to understand why so many viruses or bacteria haven't evolved to be harmless (specifically, I don't know of any harmless virus). I think it would be greatly beneficial for a virus to ...
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5answers
9k views

Why haven't prey evolved the ability to always outrun their predators?

I can understand why some prey can't outrun a recently evolved species. However, since cheetahs have existed for so long, why haven't its prey evolved to always outrun it, driving cheetahs to ...
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0answers
32 views

Identity By Descent vs Identity By State

Background The concepts of Identity By Descent (IBD) vs Identity By State (IBS) are central in population genetics, yet I fail to fully wrap my head around the definitions. You can find examples ...
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1answer
35 views

Hardy-Weinberg equilibrium generalized to add inbreeding (non-random mating)

Background Quoting from Gillespie's book The level of inbreeding is measured by the inbreeding coefficient, $F_I$, which is the probability that two alleles in an individual are identity by ...
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3answers
288 views

Is there any evolutionary advantage of selection of L-amino acid over D-amino acid?

After listening to a scientific talk, I had this question that why in the natural selection process, are the L-amino acids selected over the D- form. However, we still we produce D-amino acids; ...
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1answer
48 views

What are anagenesis and cladogenesis?

Are they two types of speciation? I have read wikipedia but can't figure out if they are really two types of speciation
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2answers
500 views

Key points of Wagner's theory of innovation

What are the key points of Andreas Wagner's "theory of innovation" from his book The Origins of Evolutionary Innovations? Specifically: What is new in his theory? What problems in evolutionary ...
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0answers
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Population size and genetic drift - What are the evidences?

Wright-Fisher model From the Wright-Fisher model of genetic drift, the random sampling of allele from one generation to the next is taken from a binomial distribution with parameters $2N$ and $p$, ...
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1answer
72 views

Under what circumstances does Batesian mimicry evolve? [closed]

Batesian mimicry is a form of biological resemblance in which a noxious, or dangerous, organism (the model), equipped with a warning system such as conspicuous colouration, is mimicked by a harmless ...
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1answer
42 views

Why aren't we immune to the “cold” [duplicate]

As far as I know, people suffer from the cold since ever. Why didn't and don't we evolve to resist it?
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6answers
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How is evolution possible in contemporary humans?

I would like to know if evolution is continuing to happen in modern humans, assuming things like existence of the nuclear family structure, fidelity to one partner, etc. It seems to me the answer ...
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1answer
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Why is chlorophyll green? Isn't there a more energetically favorable color? [duplicate]

Chlorophyll being green means it absorbs light in the red and blue area of the spectrum. Isn't this the high and low energy light? Wouldn't plants get more energy if they absorbed light in the green ...
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1answer
51 views

Is the birds' decision to fly away congenital or learned behaviour?

I see two possibilities how could the birds know what to do every fall: The birds' migrations are driven entirely by the vertical memetics and today it is just a custom transferred from parents to ...
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1answer
35 views

Is there a difference between macroevolution and group selection?

I encountered two different attitudes towards macroevolution: The first one included long-term microevolution such as the evolution of Cetacea. The second one included only macroevolution in terms ...
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1answer
42 views

What's the difference between evolution fitness and reproductive success?

What's the difference biological fitness and reproductive success in the biological terminology?
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1answer
121 views

Why does evolution only involve heritable traits?

If natural selection favors a certain behavior that is learnt, then wouldn’t that behavior be found more often among a population (as more offspring will learn that behavior from their parents or ...
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2answers
501 views

Why haven't land animals evolved beyond urination?

It occurred to me (while urinating) that this would seem to be selected against because water is a scarce resource. Why are we constantly losing water we don't need to through urination? What is ...
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7answers
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How do we know that humans and chimpanzees evolved from a common ape ancestor? [closed]

Richard Dawkins in one of his videos says that Evolution is a fact and not just a theory. He goes on to say that man and chimpanzees both evolve from apes. Is this correct (Is evolution a fact and ...
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1answer
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Was Darwin aware of the difficulties behind the concept of species?

Introduction The concept of species is a very old concept that suffers from not being a natural category. There exists no single definition that would categorize living beings into groups and that ...
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1answer
246 views

Sequence evolution simulation tool

I'm looking for a tool to simulate sequence evolution given a specific mutation model and birth-death model. I'm aware of tools and packages like INDELible, Seq-Gen and PhyloSim, but they simulate ...
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1answer
48 views

Why is the probability of fixation of an allele equal to its frequency?

Introduction In a panmictic population, the probability of fixation of an allele at a neutral locus is equal to its frequency at that time. I will refer to this probability of fixation as calculated ...
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0answers
34 views

Is diarrhoea advantageous to the microbe?

Diarrhoea is a common side effect of many feco-orally transmitted bacterial infections. How does diarrhoea help the pathogen? Should it not have a selective evolutionary advantage? Do all symptoms of ...
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4answers
649 views

How did the first life form on Earth reproduce without DNA?

How did the earliest life forms exist without DNA? The most likely scenario I can think of for life happening from nothing is that, over billions of years, with trillions of water molecules and dust ...
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1answer
82 views

What is different between the pigment of giraffes and the pigment of flowers?

I saw this video created by Derek Muller and he says there that it is very unusual to evolutionary develop the colour of the skin without the pigment. That sounds reasonable but if so, what nutrients ...
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1answer
179 views

Approaches towards a theory of innovation in evolution

Evolutionary biologist Andreas Wagner writes in his book "The Origins of Evolutionary Innovations: A Theory of Transformative Change in Living Systems" (Oxford University Press, 2011): We are ...
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2answers
69 views

Infer gene frequency within a species over time

I was reading Karlsson et al. (2014) and I came into this: A selected variant that increases rapidly in frequency in the past ~250,000 years can be detected as an unusual reduction in genetic ...
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3answers
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Intuitive explanation for Kin- and Group- selection

It is known from theoretician in the field of kin selection that kin selection (inclusive fitness theory) and group selection are actually two sides of the same coin. In other words, these two ...
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1answer
69 views

Did toads evolve from frogs?

I know frogs still exist but that doesn't mean there wasn't ever a frog population that evolved into toads. Did frogs evolve into toads because their available swamp slowly went away and toads could ...
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1answer
21 views

Measuring tumor heterogeneity [closed]

I would like to ask if there's any method (established or not) in order to quantify heterogeneity found in mutations occuring in primary neoplasms and metastatic lesions (either common or private) and ...
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0answers
47 views

Is $F_{ST}$ a probability and a correlation coefficient?

$F_{ST}$ is one of the most famous and most important statistics of all of evolutionary biology. Yet, many people misunderstand it or misuse the classical results from the literature on $F_{ST}$ ...
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1answer
35 views

How to compare diversity between different ecosystems?

I've used the Shannon Wiener Diversity Index for a single ecosystem (species as categorical variables). Do you know any alternative indices, especially ones that compare diversity between different ...
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2answers
57 views

Why does the gc content deviate from 50% in prokaryotes

I have read quite some articles but I can't figure out the main reason for gc content deviation in prokaryotes. In eukaryotes I can understand it, because the genome isn't composed at random, like ...
2
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1answer
59 views

First life forms to evolve controlled flight

What was the first living organism able to fly in the skies and control their direction , not just Aeroplankton like bacteria and viruses carried by the winds but something like an winged insect or ...