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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Ecological specialization and relative abundance

I am reading Evolution in Changing Environments by R. Levin but have a hard time. Claim At page 25, Levin says as a conclusion The more efficient a caste at meeting the contingency for which it ...
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Have people in Africa already started evolving resistance to AIDS?

Are people living in areas where AIDS is rampant (for e.g. Africa), less likely to die from it than they once were because some of the people without genes/mutations that give them resistance already ...
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Why can't humans drink sea water?

Why can't humans drink sea water? It would seem to be a huge evolutionary advantage for an animal to be able to drink sea water rather than have to rely on fresh water, and it's provably not ...
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1answer
22 views

Without plant breeding and domestication, would most of the foods consumed by humans evolve to become inedible?

Would this happen? Do species evolve to avoid being consumed, especially the animal species which have no need to leave seeds?
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1answer
43 views

If crocodiles are k-selected, why do they supposedly “not age,” as in avoid senescence?

I recently saw a few sources stating that Crocodiles do not biologically age, implying negligible senescence. Basically, a 70 year old crocodile is in the same physical/health condition as a 7 year ...
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3answers
731 views

Why does sexual selection evolve beautiful features?

I have a very raw understanding of sexual selection: Say a group of females of a certain species "likes" some feature of a certain groups of males; by "like" I mean some behaviour that makes this ...
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1answer
95 views

Is evolution a predictive theory? [closed]

My feeling is that almost any observation can be explained by current evolutionary theory. Is there any example of someone developing a rigorous framework or mathematical model of how evolution works?
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1answer
34 views

How does mutualism arise? [closed]

How can a mutualism between two species arise? I have thinking about this for a while and I have come up with the following points 1.If mutualism gives one specie a competitive edge over its ...
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2answers
210 views

How quantitative is the theory of evolution right now? [closed]

We developed complex structures like eyes and brain, whose mechanisms rely on specific species of molecules and relevant chemical reactions. But we did not develop an enhanced night vision, the ...
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2answers
374 views

Why do squirrels have twitchy bushy tails?

Whenever I see a squirrel in the woods, it is always the big bushy tail flipping around that gets my attention first. A pray animal with a big bushy flag calling attention to it's self seems to be ...
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1answer
997 views

Darwin's first sketch of a phylogenetic tree

Coming from Darwin's notebook this first sketch of a phylogenetic tree became one of the most emblematic image from Darwin's work. I have a hard time to read what is written on it. What is written ...
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1answer
42 views

What are Some Classical Examples of Local Adaptation?

Question Can you please give a list of classical (textbook) examples of local adaptations? How to answer Examples don't necessarily need to include what evidence supports this specific example of ...
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5k views

What is the evolutionary reason behind the fragility of teeth?

Almost all organs in the human body have a rather large threshold within which the organ or tissue is capable of repairing itself using materials supplied by the body, whether it's made from organic ...
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1answer
35 views

A doubt on Introgression

Wikipedia says that Introgression, also known as introgressive hybridization, in genetics is the movement of a gene (gene flow) from one species into the gene pool of another by the repeated ...
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1answer
17 views

Statistical genetics: Allele frequencies that follow a Dirichlet distribution

From Foll and Gagiotti (2008) (software BayeScan). They consider a model where several subpopulation are derived from a unique ancestral population. We consider a set of $I$ loci and let $K_i$ be ...
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2answers
3k views

How can birds disperse seeds when they are able to digest them?

I've just read in a book that birds' guts can digest almost all the consumed seeds with the exception of mistletoe and loranthus (which stays stuck on the branches). On the other hand, I know that the ...
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2answers
5k views

Why is it beneficial for trees to grow that tall?

Why is it beneficial for trees to grow that tall? This sounds like a kid's question Mom, Dad... why are trees so tall? Costs and Benefits There are some obvious ...
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1answer
57 views

Is there selection against long proteins and long genes?

Background thought Titin and TTN Titin is the largest protein in the human genome with 33423 amino acids. Titin is coded by the gene TTN that must be at least $3 \cdot 33423 \approx 100kb$ long. ...
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161 views

Up to date, extensive documentary about dinosaurs?

I just finished reading the Wikipedia page about dinosaurs, and I very much enjoyed it. I knew that much of what I learned in the 80's as a child is (and was) incorrect, and now that I am a parent, I ...
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2answers
47 views

Simple computational biology project for AP Biology class. Ideas? [closed]

Our teacher assigned us a project to do with an extremely open-ended prompt and it should be completed within a month. I was planning on doing something related to computation and evolution in terms ...
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27 views

What model of epistasis best fit the reality?

In theoretical population genetics, it is very common to have to assume a model of epistatic interaction. The two most common models are the additive model and the multiplicative model. Additive ...
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54 views

Disposable Soma Theory and the case of the contraposition

According to August Weismann (1889), Kirkwood and Holliday (1979): Because of the evolution of an organism that is segregated into soma and germ cells, soma becomes disposable, and in the face of ...
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1answer
50 views

Evolution & Celluar Chemistry [closed]

I'm new to this site but had a question on evolution, apologies if some of these questions seem basic but they are from a book i am reading challenging the role of chance in evolution. Taking the ...
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0answers
22 views

Ewens-Watterson Test of Neutrality

The Ewens-Watterson test is one of the first test of neutrality (of no selection). Later came tests such as Tajima's D or Fu, Li's G and many other. Question Can you please make a description of how ...
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Is Mutation Theory still “valid” for complex organisms?

I'm afraid like most people I suffer from having learned "A History of Evolution" in school, rather than cutting to the chase and learning the actual "up to date" version of the subject. (Imagine if ...
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1answer
22 views

How to incorporate intraspecific variation in discrete characters in comparative analyzes?

I'd like to run a multivariate analysis (Pavoine et al. 2011) that aims to disentagle the effect of environmental gradients on traits, considering its autocorrelation with phylogeny and space. It uses ...
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2answers
8k views

What is the evolutionary advantage of red-green color blindness?

Red-green colorblindness seems to make it harder for a hunter-gatherer to see whether a fruit is ripe and thus worth picking. Is there a reason why selection hasn't completely removed red-green ...
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1answer
458 views

Cyanobacterial photosynthetic oxygen yield

I am somehow not convinced that biotic factors are solely responsible for creating 21% of atmosphere (around 40 million moles of oxygen). There may be additional issues here. Since cyanobacteria ...
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5answers
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Why don't mammals have more than 4 limbs?

Arthropods have 6 or more limbs and arthropods with 6 limbs appear to move faster than arthropods with 8 limbs so I wonder whether this might have something to do with fast and efficient locomotion. ...
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1answer
36 views

Relationship between genetic diversity within and between species

Here is a quote from Wagner (2008) A second line of evidence [against neutralism] comes from the relationship between the mean number of polymorphic differences between alleles within a species, $\...
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13 views

Are there any pre-existing evolutionary explanations for the viscosity and abundance of canine mucus?

If there is, it's not something you find on search engines. To be honest, I first posed this question in a "Bad Ad-hoc Hypothesis" convention kind of context, but now I'm curious if there's any real ...
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1answer
593 views

What are the atmospheric requirements for large dinosaurs?

What are the atmospheric requirements for large dinosaurs? and are the atmospheric constituents for supporting large dinosaurs any different from the atmosphere today?
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191 views
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313 views

Are there natural selection experiments that quantitatively agree with theoretical modeling? [closed]

Has anyone ever conducted an evolution experiment and quantitatively compared it to theory? For example, has anyone ever put bacteria in a million petri dishes filled with antibiotics and calculated ...
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8answers
6k views

Why does evolution not make our life longer?

Why does evolution not make life longer for humans or any other species? Wouldn't evolution favour a long life?
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Is salivation decrease during sleep beneficial?

Papers [1, 2, 3] tell that a salivation decrease is not only unpleasant, but harmful for dental health. What cause that decrease? What is the reason for it and do animals have it? I guess it's a ...
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Did the Great Oxygenation Event also cause a mass extinction?

Its usually assumed that the Great Oxidation Event around 2.3 bya caused a great extinction of anaerobic life on earth. But as I was reading Nick Lane's book, ...
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945 views

Why would lethal genes evolve?

I've been reading through 'The Selfish Gene' by Dawkins. At a few places in the book he states that incest is damaging because it would give a very high chance of lethal recessive genes becoming ...
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38 views

Biological species concept [duplicate]

I could not understand a portion of an article I was reading. It was about biological species concept and it said ' There is difficulty in the application of biological species concept in those ...
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1answer
142 views

Mutation-drift equilibrium and among loci variance in heterozygosity

At mutation-drift balance, the increased heterozygosity brought by new mutations is exactly equal to the loss of heterozygosity due to genetic drift. At equilibrium, the expected heterozygosity for a ...
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82 views

How does the introduction of clones would affect population genetics? [closed]

Since the ability to clone animals gives another way to preserve species, this could help for the breeding process. It has been noted that with the ability to clone animals, endangered species can ...
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1answer
144 views

Selection Pressure on Orca Whale Coloration

What is the proposed selection pressure that leads to the distinctive coloration of Orca whales? I can find nothing in the literature.
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42 views

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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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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291 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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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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4k 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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14 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. ...