Changes in the heritable attributes of populations of organisms over time. Major mechanisms include drift, natural selection, mutation, and gene flow (migration).

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Why doesn't lard taste good? [closed]

I mean looking from evolutionary perspective sugar tastes sweet and individuals that had this perception ate more sugar and survived and those that didn't perceive sugar as sweet didn't eat it and ...
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91 views

Why does Citric Acid occur in Citrus fruits?

Why is there so much citric acid in citrus fruits? And how did it evolve i.e. what did it come from? Is it a by-product of the ripening process? Why have citrus fruit evolved a particularly high ...
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23 views

Effect of sex-ratio on the effective population size

As stated on this wikipedia article, the effective population size $N_e$ when the sex ratio differs from $\frac{1}{2}$ is $$N_e = \frac{4N_mN_f}{N_m+N_f}$$ I understand the biased sex-ratio ...
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33 views

Games with non-uniform interaction rates

Background: Many models in evolutionary game theory assume uniform interaction rates. For instance, consider the $2\times 2$ game: \begin{array}{l c c} & A & B \\ A & a & b \\ ...
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Why does our body exhibit bilateral symmetry? [duplicate]

Externally, we (humans) look symmetrical. However, internal organs don't show the same patterns of symmetry (heart being on the left side while the liver is on the right side, etc.). It is a bit ...
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70 views

How to understand relatedness in an infinite island model?

My understanding is that the relatedness coefficient in kin selection models measures positive assortment. That is, altruism is more likely to evolve if altruists tend to interact with other ...
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4answers
148 views

The selective pressure of contraceptives

Does it seem probable that the existence of contraceptives (which has reduced human reproduction to below survival-level in many populations) will be a completely new selective pressure on human ...
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84 views

Understanding the meaning of $s$ and $t$ in a population genetics equation

Sewall Wright in this article (1937) at the end of page 313 gives the equation: $$\Delta q = (s+tq)q(1-q) \space\space\space\space\space\space\space\space\space(1)$$ This equation is an ...
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19 views

Evolutionary motivation behind number of neurons in DCMMP

I'm studying neuro-anatomy right now and I was surprised to learn that there are only three neurons along the Dorsal Column Medial Lemniscal Pathway (DMLP) which relays mechanical sensations from the ...
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115 views

Why do baby mammals tend to play? [closed]

Why do babies of any mammal tend to play ? From humans to small dog pups, cubs of a lion, baby bears, etc. *I am not sure if the tag I chose is correct or not. Please correct me if I'm wrong.
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53 views

$F_{ST}$ and the genetic variance in metapopulations

From this video (21'15''), the speaker gives the following formulae in order to calculate the between and among populations genetic variance from the $F_{ST}$: $$V_{Among Pop} = 2 F_{ST}V_G$$ ...
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59 views

Inbreeding Coefficient and Coefficient of Relationship

Wikipedia gives the following formula to calculate a "path of coefficient of relationship" between an ancestor $A$ and an offspring $O$: $$\rho_{AO} = 2^{-n} \left( \frac{1+f_A}{1+f_O} \right)^{1/2} ...
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29 views

What is the origin of viruses? How could they get both living and non-living characteristics? [duplicate]

I read that viruses are called intermediate between living and non-living particles. Well, if so, then where did they originate from? From living or non-living? If they originated from either living ...
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1answer
657 views

What is needed for a G-matrix?

I have been doing a lot of reading on quantitative genetics and the G- (and B-) matrix lately. I get the principle behind performing the analysis now but I am still not sure how to do it. I'd like to ...
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2answers
392 views

What are evolutionary implications of contraception and reduced childhood mortality rates worldwide?

I've heard the following idea this morning: Before the introduction of contraception, humans conceived quite a lot of babies (there was little to do to avoid that), but the population was kept in ...
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2answers
2k views

Why do humans bury their dead? [closed]

As far as we know Ape Men or the Neanderthal Man was the first to bury its dead. My question is why. I don't think they practiced religion or believed in spirits or faith or stuff like that. ...
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3answers
174 views

Evolution (Reductionism)

My recent post was tagged as unclear so I wanted to re frame my question. Though I am a layman, I would love to read books and find the stuff, if I get an overall picture of intelligence factor. My ...
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2answers
195 views

Why asexual reproduction?

When I took a course on genetics and evolution, I learned that recombination and sexual reproduction is advantageous compared to asexual reproduction. Sexual reproduction allows more combinations of ...
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4answers
347 views

Are we inevitable in the evolution?

Suppose we wind time back to the instance when life emerged on Earth and let evolution start over again, will human beings or any other kind of self-conscious animals evolve ultimately, inevitably? ...
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3answers
628 views

Is there an evolutionary purpose to armpit perspiration?

Given that most Americans seem to do fine using anti-perspirant, it got me wondering: is there an evolutionary purpose to underarm perspiration? I can't imagine it acts to attract the opposite sex. ...
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1answer
541 views

Fossils of intermediate stages?

If Humans are evolve from Monkeys, there must be stages in the evolution process, when it was 1% human and 99% monkey, 2% human and 98% monkey and so on. This is because evolution was a very slow ...
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334 views

Where are the evolutionary “inbetweeners”? [closed]

The problem I've always had with evolution is the actual lack of variation between animals. More specifically, the lack of observable gradual change between species. Take for example the hammerhead ...
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1answer
134 views

Before Evolution was proposed by Charles Darwin, what were the leading secular theories to explain how life developed? [closed]

Outside of evolution, what were the leading scientific schools of thought that Charles Darwin contented with when he published his evolution theory as way of natural selection in 1859?
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435 views

What modern insects are not (flying OR descended from flying ancestors)?

What modern insects are not flying or descended from flying ancestors? (I read somewhere that 99% are, so of course I instantly became curious which aren't. xD ) EDIT: Sorry, I should have been ...
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5k views

What factors are known to affect evolution?

My understanding is that the possible mechanisms of evolution are: Environmental changes Cultural/mating preferences Population Immigration Genetic Mutation Am I missing anything? I've heard that ...
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3answers
134 views

How did the horned lizard evolve?

It's a lizard that has the ability to burst blood vessels in it's eyes and shoot blood as self defense. How can this behavior be explained evolutionary? Wouldn't it mean that there had to be some ...
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3k views

Why do different humans look different?

Although farmers appear to be able to tell their cows apart, cows look very much alike to me. And this similarity in appearance seems to be a general trait across the animal kingdom: one individual of ...
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128 views

Have proteins been observed to come into existence through mutations and natural selection?

A protein that catalyzes one reaction can theoretically be modified by mutations and natural selection and eventually catalyze another reaction completely unrelated to the original. Has this been ...
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1answer
401 views

Did spiders respond to light for building webs before artificial light was invented?

I have noticed that during summer, beautiful spider colonies grow wherever a strong light is: I'm wonder whether spiders evolved to seek naturally lighted areas where they build nests (before ...
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2answers
74 views

Conservation Genetics - Book recommendations

Can you please give me some advice for a book in (evolutionary) conservation genetics that offers an in-depth review of the mathematical formulations used in this field. I read the book Evolutionary ...
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2answers
144 views

What is doubling of genetic material invented in flowering plants?

David Attenborough in his Kingdom of Plants 3D said, that flowering plants made two inventions: (1) doubling of genetic material and (2) symbiosis with animals. What was meant by "doubling of genetic ...
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794 views

Are there genetic similarity between humans and pigs that don't exist in chimps?

Chimps are our closer relative. Any genetic similarity between humans and chimps must exist on the common ancestor. Pig branch out sooner. So, any genetic similarity between humans and pigs must be ...
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1answer
904 views

Why are urban birds still scared of humans?

I understand that animals are naturally scared of humans because we basically slaughtered every living thing we found in our way for millennia. How long does it take for them to genetically 'forget' ...
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325 views

Why are some fungi poisonous?

There are many poisonous fungi in nature. For example Amanita Phalloides. What reasons could a fungus need poison for? Some species, like venomous snakes, use poison to kill other species as prey. ...
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105 views

Evolution after the development of sexual reproduction

My understanding of evolution is that genetic mutation occurs in individual members of a species, and they become a new species. Isn't a definition of species a group of genetically similar organisms ...
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1answer
124 views

Why do Lapidaria margaretae look like stones?

Previous Research I stumbled across a trending reddit post "Lapidaria margaretae looks like stones" (as of 3rd Februrary 2015); but I could not find discussions as to reasons behind why. Question/s ...
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255 views

On evolution statistics [closed]

This basic evolution theory question has been haunting me since childhood and I'm kind of embarrassed that I can't explain it yet: Consider a butterfly. It's wings have evolved to look like the eyes ...
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1answer
4k views

What is the difference between these terms: clade, monophyletic group and taxon?

Wikipedia definitions for these terms are pretty similar: http://en.wikipedia.org/wiki/Clade http://en.wikipedia.org/wiki/Monophyletic_group http://en.wikipedia.org/wiki/Taxon They sound like the ...
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2answers
657 views

How did the first sexual animal come to exist? [closed]

I am more or less familiar with the evolution theory based on mutations. Now, starting with a nonsexual being, how did the first organism that reproduces sexually come to exist.
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161 views

Agony, Hydrophobia and viruses in the light of evolutionary principles

I'm undergraduate physics student, but I've always been interested in biology. So I have a couple of questions about an application of the evolutionary principles to practice. Agony as the last ...
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1answer
54 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 ...
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1answer
158 views

Largest direct ancestor of humans

Going back the genealogical lineage from present humans to the beginning of life, what was the biggest - in terms of body size or mass - animal in this sequence? More generally, what would a time vs. ...
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2answers
126 views

Definitions of robustness and canalization

The concepts of robustness and canalization are fashionable today in the biology literature. However, I am not sure of their definitions and I am not sure either that all authors actually use the same ...
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2answers
155 views

Do couples having children later in life act as an evolutionary mechanism?

Ok, this may be just wild nonsense and I have to warn that my knowledge on the subject is limited. I was reading about how in some countries people choose to have children later in life. After that ...
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3answers
6k views

Why do our eyes close when we sleep?

Why do our eyes close when we sleep? Is it to relax our eye muscles? How can it be explained from an evolutionary point of view?
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1answer
49 views

Definition of Linkage Desiquilibrium (LD)

According to wiki, linkage disequilibrium $D$ equals $$D = x_{11} - p_1\cdot q_1$$ where: $$ \begin{matrix} \text{Haplotype} & \text{Frequency}\\ A_1B_1 & x_{11}\\ ...
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1answer
74 views

Effective population size when the population sizes varies from season to season

Let's think of a species which has four generations per year and which population size changes from season to season so that the population size is 100 in summer, 200 in spring, 50 in autumn and 20 in ...
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4answers
72 views

What evidence do we have to derive a rate of evolution?

When analyzing how the human species evolved and will continue to evolve over time, what evidence and tools (theory/models) do we have available to derive the rate at which this happens? Is it even ...
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1answer
917 views

Why were dinosaurs not as smart as we are?

According to http://en.wikipedia.org/wiki/Dinosaur, Dinosaurs were the dominant terrestrial vertebrates for 135 million years. They had a lot of time to evolve. My question is: why were dinosaurs not ...
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1answer
1k views

Female preference for males who are already in a relationship [closed]

A common saying is that women are generally more attracted towards men who are already in a relationship, and this phenomena does seem to have its own place in popular culture that is not matched by a ...