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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Why does the wavelength in curly hair differ?

Different people and animals have different wavelengths in the curls in their hair. I understand what purposes hair serves in protecting the skin from light and bugs. I am wondering about the eventual ...
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Relationship between lifespan and reproductive age?

I remember reading a while ago that there is a "general rule" in biology between an animals lifespan and when they reach reproductive age. In other words, an organism that reaches sexual maturity ...
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Are heterozygotes always fitter than homozygotes? Can inbreeding be beneficial?

Inbreeding is mostly not very good because when there is a 'disease' in one allele, the other could/would take over the function. But when you have two of the same genes/alleles, do they, or could ...
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64 views

Why do horses recycle their endometrial lining while humans don't?

How does not recycling the endometrial lining of the uterus benefit humans (and other organisms that menstruate), while recycling it is beneficial to horses (and other organisms that undergo estrus ...
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362 views

How do traits with no negative effects get “weeded out” via evolution?

If only those who are most fit to reproduce are the ones reproducing the most, it makes sense that traits that prevent one from reproducing would eventually disappear from a population. But what ...
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88 views

What's the correct name for the war of sexes in evolution?

I'm searching for the correct term for the part of the selfish gene evolution regarding sexes. In nature, this means the evolution of the traits such as the ducks' adaptation to "trap" the drakes' ...
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64 views

What is the difference between natural selection and adaptation?

From what I've read it seems that the only actual difference is that creationists use adaptation and people who believe in evolution use natural selection. But otherwise, from my understanding, the ...
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159 views

Why are the human knees and elbows bent in an opposite direction

I can assume that the hands used to be the same as legs. And they got weaken, and changed direction when human started to walk on two? Also why do the hand palms facing the body and not facing down ...
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19 views

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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127 views

Hamilton's Rule in practice

I came across this question in USABO 2013 open exam: A mother antelope and its child are galloping along the plains, when they encounter a group of hungry lions. If the two antelopes try to escape ...
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25 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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45 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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99 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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36 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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1answer
1k 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
61 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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138 views

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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19 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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56 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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58 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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138 views

What were the camels' humps good for back in the polar areas?

I've heard that camels lived in the North America formerly and just in the last few thousands years they've migrated to the hot deserts. Thus they allegedly utilized the adaptations against the cold ...
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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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29 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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42 views

What negative effects does cannabalism have in other species (like prion diseases) and how are they mitigated?

It is well known that human cannibals are likely to suffer from a variety of ailments, particularly prion diseases. However a great many other species, from insect to ape practice cannibalism at much ...
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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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30 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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1answer
47 views

Determination of genes to be modified in epigenetics [closed]

It seems that during reproduction particular genes are targeted for modification (mutation, deletion, insertion, etc.) given environmental inputs of either or both of the parents. If a creature was ...
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55 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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37 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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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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13 views

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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50 views

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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966 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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39 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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84 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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43 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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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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42 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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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. ...
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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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66 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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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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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
121 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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1answer
73 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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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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80 views

How to read cladograms/phylograms?

I understand the difference between cladograms and phylograms; the latter can show the evolutionary linkage over time. However, I am having trouble finding out which two organisms are most closely ...
2
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1answer
47 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
37 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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Evolution to store limited Fat

Why are our bodies not evolved to store only limited amounts of fat, which won't kill us with all diseases associated with obesity? Wouldn't obese people die faster and clean the gene pool for people ...