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 human facial and head hair continue to grow?

Many people can grow extremely long head hair and facial hair. Are there evolutionary theories as to why this is the case? It seems like having long hair could be a disadvantage, and extremely long ...
5
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2answers
53 views

Is there a name for this phenomenon described in “Phylogenies and the Comparative Method”?

The figures below are from Felsenstein's paper "Phylogenies and the Comparative Method". I was wondering if there was a specific name for this effect where there is an apparant correlation that is ...
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1answer
62 views

Altruism in viscous (asexual) populations

The viscosity of a population is the tendency of offspring to remain near their place of birth. Taylor 1992 ("Altruism in viscous populations") provides a model to study how viscosity affects the ...
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1answer
2k views

How did the huge dinosaurs cope with gravity and loads on bones, etc.?

It's very costly to be a huge animal. Your mass grows in cube when you scale up, but you still only have two/four legs to support the same weight. This increases the pressure that your body needs to ...
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2answers
99 views

Characters do not make the genus, but the genus gives the characters?

In his Origin of species, in the chapter entitled 'Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs', Darwin, speaking of the nature of classification systems of living ...
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297 views

Why don't mosquitoes evolve towards muting themselves?

Quite certainly, muted mosquitoes would be much more effective as far as their blood-sucking pursuits are concerned, since mosquito sound is predominantly responsible for sealing their fate (between ...
3
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1answer
407 views

Opposite results between Blomberg's K and phylogenetic signal in Phylocom (AOT)

I've been trying to test for significant phylogenetic conservatism in some plant traits. So far I used R-package picante (Blomberg's K) and AOT in Phylocom. So far these two methods yield completely ...
9
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1answer
814 views

How and when did a dedicated immune system evolve?

I have recently been doing a lot of research into the interplay between the innate and adaptive immune systems in humans, and mammalian laboratory models. This has led to my reading some interesting ...
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1answer
68 views

What is a selectively neutral genotypic change?

I am reading the paper "Neutral evolution of mutational robustness". Because I am new to neutral evolution, I have a few questions. Firstly, from my understanding, genotypic neutrality means the ...
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2answers
501 views

Can we make a rough estimate of the number of generations since the origin of life?

According to what we've learnt : we can approximate the number of generations since the first human pretty much like us (depending what / who we talk about). we have an idea of the series of life ...
3
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1answer
189 views

How does rate of evolution/innovation scale with population size?

I understand that there will be many other factors that affect rate of evolution/innovation. However, other things being equal, how will the rate of evolution vary between two populations of different ...
2
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1answer
54 views

Why is an increase in the amount of oxygen in the atmosphere favorable for life?

I have followed the David Attenborough series on 'First life' and heard, that an increase in the amount of oxygen in the atmosphere, as it took place just before the Cambrium, is generally favorable ...
6
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1answer
53 views

Independent contrasts with non-homologous traits

I have morphometric measurements for a trait across various animal taxa, and would like to study the relationship between the size of this trait, and the animals' body size. In theory, I can account ...
5
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1answer
94 views

How are behaviors genetically coded in animals?

I am curious as to how complex behavior is passed down genetically? For example, how is the building of a web genetically coded in a spider? And how is the complex behavior of constricting prey coded ...
2
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0answers
56 views

Differing number of “things” in mammals [closed]

I'm not a biology expert, but I have often wondered about the following facts of life: All mammals have precisely 5 fingers on each of our 4 extremities. Granted, some may not be seen, but the bone ...
1
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1answer
116 views

Why is the gene regulation in eukaryotic cells needs multiple level of control than in prokaryotic cells?

That "eukaryotic cells are more complex" and "compartmentalized" are used to justify the need of more level of control of gene expression. I get the basic idea but can't convince myself why complexity ...
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4answers
414 views

Why don't most animals have “heads” in the middle of their bodies? [closed]

For example, humans. It would seem like, to me, if our brains and eyes, ears, etc. were situated in our stomach area they would be more protected from harm and more central than up at the top in and ...
6
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3answers
513 views

Is homosexuality an adaptation in humans?

Homo sapiens have menopause - as some other mammals (e.g. some Cetacea) - a phenomenon where older females live for decades after the end of their own reproduction. Perhaps homosexuality, that looks ...
5
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1answer
76 views

Queller's 1985 version of Hamilton's rule

Queller 1985 ("Kinship, reciprocity and synergism in the evolution of social behavior") provides a generalization of Hamilton's rule that allows for non-additivity. To accomplish that, Queller writes ...
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1answer
93 views

Basic Modelling in Quantitative Genetics

I am pretty bad in thinking quantitative genetics models. I am trying to get some basic understanding of modelling the evolution of a quantitative trait. I am therefore asking for help to analyze a ...
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0answers
12 views

Are amantadine and rimantadine MOAs unknown to evolution?

Are any natural (human or otherwise) antiviral mechanisms similar to the antiviral mechanisms of amantadine and rimantadine, or are these mechanisms undiscovered by evolution? Are drug researchers ...
5
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2answers
64 views

What ways are there to determine how big genera are?

I want to look at genera as a whole, across the animal kingdom to determine the range of sizes of genera. I have examined species richness and genetic diversity (pairwise distance from sequence data ...
5
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1answer
65 views

How to seek for available genetic data relevant to ecology and evolution?

I had a quick look online. There seems to exist many different website of database archiving. Some data might be free of charge while some others might not be. I found things such as Dryad, TreeBase, ...
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1answer
169 views

Can pandas hunt for meat?

Recently, I learned that pandas have a carnivore's digestive system but that it exists almost exclusively as a herbivore. If pandas hunted would they be able to find meat in their environment? Can't ...
8
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1answer
255 views

Why do we find some things disgusting and others delicious?

For example, why do I love paprika while my girlfriend hates it? Why do I find broccoli disgusting and she adores it? As humans, there are things we'd all agree on being awful, like rotten meat, for ...
14
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2answers
500 views

Have we ever observed two drosophila lineages that evolved reproductive isolation in labs?

Background The standard definition of species refers to the concept of reproductive isolation. If two lineages are found to be reproductively isolated, then we consider these two lineages to belong ...
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1answer
585 views

Evolution of umbilical cord and reason of its elongation

To answer a question myself, recently I've read that Years and years ago, a long umbilical cord enabled a woman to grasp her baby after birth and run away from predators" Update: $Question:$ ...
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4answers
10k views

Why 22 amino acids instead of 64?

This question got me thinking about amino acids and the ambiguity in the genetic code. With 4 nucleotides in RNA and 3 per codon, there are 64 codons. However, these 64 codons only code for 22 (...
2
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1answer
116 views

What would be required to evolve an animal (non-human) brain to obtain human-level cognition? [closed]

Could any animal subject to the right conditions evolve human-level intelligence? Suppose that an artificial intelligence (AI) decided to artificially evolve a population of octopus (don't ask why, ...
2
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1answer
55 views

Evolution and Phenotypes.

This may be better suited for the English language SE, but When discussing evolutionary changes in species is it proper to refer to their phenotypes? In this context: "Imagine if a cow did not ...
5
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1answer
78 views

How do bumblebees and hornets avoid the negative effects of inbreeding?

I just learned that all hornets and bumblebees except for the queen die at the end of the year and the queen starts a new nest in spring. But that means the next generation of queens have only ...
6
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1answer
87 views

Why are abiogenesis and evolution considered unrelated?

When a discussion about evolution comes across abiogenesis - the typical reaction is that they are unrelated (see the headline at http://www.factsnotfantasy.com/abiogenesis.php). It seems to be ...
3
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2answers
62 views

Terminology for inefficacy of selection on recessive alleles

I am wondering is there some proper terminology which is used to say that deleterious recessive alleles might be able to hide, reducing the the efficacy of selection, in diploid organisms/chromosomes. ...
7
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2answers
88 views

Is there a name for the evolutionary loss of vestigial structures?

Consider a biological structure which no longer benefits an organism, such as the eyes of an organism whose population now lives in total darkness. I can think of three reasons why such a structure ...
7
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1answer
917 views

Term for trait that is advantageous to a population only as long as it is rare

I remember reading about a concept—in evolutionary biology or natural selection, I think—whereby a particular trait is advantageous to the population or species but only so long as that trait is only ...
0
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1answer
90 views

What is the point at which abiogenesis is complete and evolution begins? [closed]

Is the minimum criterion for life a single cell? It seems that self-replicating RNA is not enough, but I don't know. What would be the most basic cell that could fit this criterion and what cells ...
3
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1answer
144 views

Any evolutionary explanation for human blood groups?

What is the explanation of people having blood types from an evolutionary perspective?
3
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1answer
106 views

Why do cows (and other hooved animals) need a hierarchy?

Clearly numerous animals have a hierarchy - hereditary one. For example, I understand zebras have a pecking order, and must map this hierarchy from highest to first in line and lowest to last in line ...
3
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1answer
484 views

How did the endoplasmic reticulum come to be?

Organelles are sub-cellular compartments in cells. However prokaryotes don't use organelles to organise their intracellular space. Evolutionarily, there is evidence that mitochondria and ...
3
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2answers
1k views

Why has our nose evolved with the nostrils facing down?

For most animals, the whole bottom of their face sticks out and they have a snout with a mouth and nose at the end. But humans have a flat face and just a nose that sticks out. We used to have the ...
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3answers
81 views

how to find accurately the closest species to my plant species?

I'm working on some bioinformatic analysis of a non-model woody plant within the family with least information. So, I'm looking for a closest species to my plant. Any suggestion would be highly ...
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0answers
57 views

Evolution of Wheat

In the evolution of wheat, there are two instances of chromosomal doubling, when Emmer wheat Triticum turgidum was formed from Einkorn wheat, and when Triticum aestivum was formed from Emmer wheat. ...
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0answers
33 views

Analytical Methods for Estimating Probability of Fixation

The probability of fixation $P$ of an allele is an very important measure and there exists several solutions to estimate this probability. Each method has its own assumptions and it is often hard to ...
0
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1answer
65 views

Would it be more genetically efficient to have shorter lifespans?

If, for example, humans had an average lifespan of, say, 30 years, and we reached sexual maturity at age 10, then we could "evolve" more quickly and theoretically "weed-out" more genetic diseases ...
2
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1answer
60 views

Very introductory online source of information in evolutionary biology

We receive quite a lot of questions from layman in evolutionary biology in this site that are sometimes difficult to answer just because there is way too much to say. Why don't human keep evolving? is ...
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2answers
55 views

How to compute the regression of individual fitness on individual phenotype

Consider a population structured in groups of two individuals. Individuals' interactions follow an additive prisoner's dilemma: \begin{array}{c |c |c|} & C & D \\ \hline \text{Cooperate (} C \...
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1answer
153 views

Interlocus Contest Evolution means suicide?

I was reading Matt Ridley's "Genome" book. I am trying to understand the Interlocus Contest Evolution in his X-Y chapter. I do not understand why the X and Y chromosome would want to kill each other. ...
1
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1answer
83 views

History: Building a “Phylogenetic network” of famous evolutionary biologists [closed]

Seems like many of the famous evolutionary biologists are somehow related to each others. For example (and I might be mistaken), Ronald A. Fisher was mentored by a descendent of Charles Darwin. Joe ...
2
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1answer
122 views

Are there any examples of how to apply evolutionary models?

Apologies if this question it too open-ended; evolutionary biology is not my primary field. I have been reading a lot about the use of statistical mechanics in analyzing evolutionary dynamics. As an ...
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85 views

Does embryonic development mimic (partly at least) the evolution of organisms on earth?

What do we know about the forces/mechanisms which lead to this seemingly "fast forward" evolution stages of the embryo? What are the theories dealing with this idea?