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 do spiders have a leaf at the bottom of a piece of web?

I've lately seen a lot of instances where a leaf is dangling from a piece of web coming down off a tree. What purpose/s does this serve for the spider? Is it some sort of mechanism for the spider to ...
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Regarding inherited fertility in animals

If an animal is fertile does it follow that both its parents of the same species (not necessarily the same species of the offspring)? Was it Mayer who said a fertile male and fertile female of two ...
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57 views

Fisher's Geometric Model for Dummies

Fisher's geometric model is still today one of the most important and fundamental model in evolutionary biology but it seems to me that most student in evolutionary biology don't really understand it ...
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1answer
27 views

Evolutionary support for parenting book “The happiest baby on the block”

The book by Dr Harvey Karp (MD) The Happiest Baby on the Block proposes that the duration of human gestation has evolved as a tradeoff between cranial size and development of the infant. He ...
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1answer
53 views

Can we influence evolution by teaching primates to control fire? Should we?

Most people with a strong interest in biology will have heard of Kanzi the Bonobo, the ape that has the wherewithal to collect fuel for a campfire and play pac-man. But is it conceivable to influence ...
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1answer
68 views

How closely related are two parasites Giardia intestinalis and Trichomonas vaginalis?

How closely related (from the evolutional point of view) are parasites Giardia intestinalis and Trichomonas vaginalis? Giardia genome is about 12 Mb and its major cellular proceses are rather simple. ...
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60 views

What is the “Spandrels” debate about?

In a former question, as a side question, I asked a clarification about the "Spandrels" paper. Being not a biologist, it was the first time I encoutered it. Subsequently I tried to collect some ...
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1answer
74 views

Why do baby mammals tend to play?

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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Evolution 15 + 15 [closed]

If I flap my hands for say, about 1hr everyday, and I teach my future children to repeat this and so on, theoretically (at least), how many generations would it take for my grand [sons ...] to be ...
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57 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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3answers
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Evolution of bird wings

In this answer on aviation.SE a comparison is made between the shapes of airplanes wings and the shapes of birds wings. It concludes with the following remark: After all, no bird has winglets. Not ...
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1answer
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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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55 views

Is the mutation rate in organisms in general consistent over the genome?

Coming from computer science with an interest in genetic programming (a process emulating evolution) I'm curious about whether the rate of mutation is homogeneous across the whole genome, or if some ...
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3answers
78 views

Conscious evolution

Does intelligence play a vital role in the evolution of an organism? In other words does an expansion of learning capacity increase the odds of evolution for the particular biological entity?
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How does Natural Selection Shapes Genetic Variation?

Background Importance of the additive genetic variance As stated here, the fundamental theorem of Natural Selection (NS) by Fisher says: The rate of increase in the mean fitness of any organism ...
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1answer
67 views

What does “Mutational Variance” mean?

Background The concept of mutational variance can be found in many articles including this one for example. The mutational variance of a trait number $i$ can be found in the M-matrix in position ...
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2answers
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Did Darwin ever reach the conclusion that selection will remove variation?

According to simple models of selection the genetic variance in a population should be reduced by selection. (Fisher's fundamental theorem states that the rate at which a population can evolve is ...
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2answers
92 views

Is greed an evolved trait?

Thanks for looking. I am not a biologist, but I am fascinated by evolution. I was watching the news this morning and, as so often is the case, there was a news story about a corrupt politician who ...
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1answer
108 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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6answers
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Is there a biological mechanism for evolution encoded into our DNA?

Throughout high school, I remember learning about Darwin's theory of evolution as if it were near-fact. But something always seemed wrong about the ideas presented. Survival of the fittest Random ...
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1answer
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Is there any evidence that soft tissue can be preserved for 65m+ years and if not what hypotheses exist to explain it?

I read an article on howstuffworks.com and they mentioned how we have found soft tissue in dinosaurs. According to the article even Mummies and Mammoths have no soft tissue left. Is there any evidence ...
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Evolution of sexually concordant genetic variation on the X-chromosome

It was theorised in 1984 that sexually antagonistic genetic (SA) variation should more easily evolve on the X-chromosome. This is partly because female beneficial/male deleterious mutations face less ...
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Does the Y chromosome carry structural information, or only switches + traceable ID?

The Y chormosome almost doesn't crossover with the X chromosome, and so the evolution of anything it encodes must be much slower, because by the Hill–Robertson effect beneficial mutations must occur ...
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What prevents this blue lobster from becoming dominant?

Like everyone else in the world I saw the blue crustacean from becoming dominant? I would think the blue camo would be an evolution advantage.
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Main mechanism of the evolution of sexual dimorphism

Sexual dimorphism is very common and (normally) requires the evolution of sex-specific genetic variation/regulation so the genetic correlation between the sexes can be <1. Is there consensus as to ...
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When did CRISPR/Cas9 evolve and what is the likelihood that a superior system for live cell genome editing has already evolved on earth since then?

I've read that CRISPR/Cas9 is currently being implemented and tested for its ability to edit genomes in live cells, and that it is supplanting other genome editing tools in labs, such as TALENs and ...
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77 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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What can myelination tell you about the evolution of sensory receptors?

I am reading Avi Chaudhuri's Fundamentals of Sensory Perception and wondering if the information given about the somatosensory system could tell us anything about the way it evolved. It seems (at ...
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62 views

Does the fossil record disprove Evolution? [closed]

It is said by people opposed to Evolution, that the fossil record contradicts and disproves it. They say all the animals suddenly appeared, exploded everywhere, were fully formed, had no transitions, ...
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Why are recombination rates increasing in mammals?

I have recently become fascinated with an awesome topic in biology and evolution that I feel is rarely covered in biology courses. That is, rates of meiotic recombination, or the the amount that an ...
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3answers
111 views

What is the point of having evolved two nostrils?

How would having two nostrils be advantageous to your sense of smell or your ability to breath? I already hypothesized that either one of the nostrils could act as a back up for when another gets ...
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2answers
51 views

Periodic Muscular Growth in Humans

If a healthy human is at a certain muscle state and then experiences muscular atrophy solely due to disuse/lack of exercise, is it easier to gain that muscle back than if the human had never reached ...
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1answer
193 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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If evolution is a gradual and continuous process, how can we say humans came about 200k years ago? What is so special about that point in time?

It just seems arbitrary to me to say "ok, now THIS is officially a human" when you could look at its parents and find no noticeable differences. At no point in the line of my ancestral history is ...
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59 views

What's the purpose of colorful mushrooms' caps?

What's the purpose for many mushrooms to have colorful caps? Is not it is in their interest to hide as well as possible? Or there are mushrooms that propagate by being eaten, like fruits? Why not all ...
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Convergent evolution of fruits

Many fruits are not homologous, originating from different parts of a plant. Yet they all have similar properties: Ripe fruits all have yellow to dark red color They all have a lot of water and ...
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2answers
92 views

Human Evolution in Modern Times

I understand that evolution occurred to form the current hominids from a common ancestor millions of years ago. As evolutionary processes take a long time, is there proof of evolution occurring with ...
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1answer
156 views

Why Did 6 Great Ape Species Survive But Only 1 Hominid Species?

My dad asked this question when I explained some circumstances surrounding Homo sapiens survival against all odds. We know there is only one hominid species left in the world, Homo sapiens. We also ...
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298 views

Extinction of species

I barely know anything about biology and realize that this might be a stupid question, but I'll ask anyway! I know that species "transform" into other species through the process of evolution. Many ...
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3answers
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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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2answers
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Questions about the Evolution Theory [closed]

I'm trying to understand more about evolution theory. (I am coming from a mathematical background) What i understand till now is that the "improvement" of the dna is a purely random development and ...
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2answers
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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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3answers
340 views

What exactly does adaptive mean?

This is a quote from Dey et al 2014: Hatching asynchrony is thought to be adaptive because... What exactly does adaptive mean here? Does it mean hatching asynchrony has fitness benefits? Or does ...
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How to track and describe the evolution of a gene?

So I have a project student (undergraduate) who has been assigned a project to study the evolution of a gene (and possibly related genes) through species. I am not an evolutionary biologist, and hence ...
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Periods of Heavy Speciation

I have a set of microRNA ages with corresponding labels suggesting which clade they first emerged from. For instance, for hsa-mir-1, let's say, it would have an age of Eutheria. I have several peaks ...
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Why do Mangoes have a single large seed, and not multiple small ones?

I was just thinking about this, wouldn't it make more sense for a mango to have multiple seeds, as it would allow more seed propagation?
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Does documentation exist that shows the evolutionary connection between common horses and the okapi?

I'm trying to put together some documentation on the relation between the common (modern) horse and the okapi. I've found a tree that shows that connection but it has no references. I'm hoping that ...
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1answer
56 views

Gender and age-specific mutation rate in plants

Background General concept According to Cochran and Harpending (2013), mothers transmits on average a number $x$ of new mutations to their offspring. This number $x$ is independent of the age of the ...
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1answer
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Horizontal gene transfer versus convergent evolution

There are several often noted examples of convergent evolution (eyes, bat/bird wing evolution etc.) How do we rule out horizontal gene transfer in these cases?
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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 ...