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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2answers
159 views

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 ...
4
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2answers
219 views

Randomness in living systems

The point of my question is not to talk about events that are uncontrolled by living organisms. My question is about controlled randomness, or I'd like to say adaptive random process. Process that are ...
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1answer
64 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 ...
0
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1answer
69 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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1answer
44 views

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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2answers
118 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 ...
0
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2answers
61 views

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 ...
3
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2answers
720 views

Can parents' learned traits be transmitted genetically?

I am wondering whether a behavioral trait (e.g. fear or stress experienced in the lifetime of the parent) can be transmitted genetically to its offspring? I understand that a behavioral tendency for ...
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0answers
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 ...
11
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5answers
387 views

Why have parasites not evolved to be harmless?

I have yet to understand why so many viruses or bacteria haven't evolved to be harmless (specifically, I don't know of any harmless virus). I think it would be greatly beneficial for a virus to ...
1
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0answers
36 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
35 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 ...
12
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3answers
293 views

Is there any evolutionary advantage of selection of L-amino acid over D-amino acid?

After listening to a scientific talk, I had this question that why in the natural selection process, are the L-amino acids selected over the D- form. However, we still we produce D-amino acids; ...
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1answer
52 views

What are anagenesis and cladogenesis?

Are they two types of speciation? I have read wikipedia but can't figure out if they are really two types of speciation
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2answers
509 views

Key points of Wagner's theory of innovation

What are the key points of Andreas Wagner's "theory of innovation" from his book The Origins of Evolutionary Innovations? Specifically: What is new in his theory? What problems in evolutionary ...
2
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0answers
52 views

Population size and genetic drift - What are the evidences?

Wright-Fisher model From the Wright-Fisher model of genetic drift, the random sampling of allele from one generation to the next is taken from a binomial distribution with parameters $2N$ and $p$, ...
2
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1answer
73 views

Under what circumstances does Batesian mimicry evolve? [closed]

Batesian mimicry is a form of biological resemblance in which a noxious, or dangerous, organism (the model), equipped with a warning system such as conspicuous colouration, is mimicked by a harmless ...
1
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1answer
45 views

Why aren't we immune to the “cold” [duplicate]

As far as I know, people suffer from the cold since ever. Why didn't and don't we evolve to resist it?
21
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6answers
1k views

How is evolution possible in contemporary humans?

I would like to know if evolution is continuing to happen in modern humans, assuming things like existence of the nuclear family structure, fidelity to one partner, etc. It seems to me the answer ...
9
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1answer
1k views

Why is chlorophyll green? Isn't there a more energetically favorable color? [duplicate]

Chlorophyll being green means it absorbs light in the red and blue area of the spectrum. Isn't this the high and low energy light? Wouldn't plants get more energy if they absorbed light in the green ...
2
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1answer
52 views

Is the birds' decision to fly away congenital or learned behaviour?

I see two possibilities how could the birds know what to do every fall: The birds' migrations are driven entirely by the vertical memetics and today it is just a custom transferred from parents to ...
0
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1answer
37 views

Is there a difference between macroevolution and group selection?

I encountered two different attitudes towards macroevolution: The first one included long-term microevolution such as the evolution of Cetacea. The second one included only macroevolution in terms ...
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1answer
46 views

What's the difference between evolution fitness and reproductive success?

What's the difference biological fitness and reproductive success in the biological terminology?
4
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1answer
125 views

Why does evolution only involve heritable traits?

If natural selection favors a certain behavior that is learnt, then wouldn’t that behavior be found more often among a population (as more offspring will learn that behavior from their parents or ...
8
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2answers
508 views

Why haven't land animals evolved beyond urination?

It occurred to me (while urinating) that this would seem to be selected against because water is a scarce resource. Why are we constantly losing water we don't need to through urination? What is ...
26
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7answers
10k views

How do we know that humans and chimpanzees evolved from a common ape ancestor? [closed]

Richard Dawkins in one of his videos says that Evolution is a fact and not just a theory. He goes on to say that man and chimpanzees both evolve from apes. Is this correct (Is evolution a fact and ...
5
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1answer
215 views

Was Darwin aware of the difficulties behind the concept of species?

Introduction The concept of species is a very old concept that suffers from not being a natural category. There exists no single definition that would categorize living beings into groups and that ...
6
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1answer
254 views

Sequence evolution simulation tool

I'm looking for a tool to simulate sequence evolution given a specific mutation model and birth-death model. I'm aware of tools and packages like INDELible, Seq-Gen and PhyloSim, but they simulate ...
1
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1answer
51 views

Why is the probability of fixation of an allele equal to its frequency?

Introduction In a panmictic population, the probability of fixation of an allele at a neutral locus is equal to its frequency at that time. I will refer to this probability of fixation as calculated ...
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0answers
37 views

Is diarrhoea advantageous to the microbe?

Diarrhoea is a common side effect of many feco-orally transmitted bacterial infections. How does diarrhoea help the pathogen? Should it not have a selective evolutionary advantage? Do all symptoms of ...
11
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4answers
698 views

How did the first life form on Earth reproduce without DNA?

How did the earliest life forms exist without DNA? The most likely scenario I can think of for life happening from nothing is that, over billions of years, with trillions of water molecules and dust ...
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1answer
84 views

What is different between the pigment of giraffes and the pigment of flowers?

I saw this video created by Derek Muller and he says there that it is very unusual to evolutionary develop the colour of the skin without the pigment. That sounds reasonable but if so, what nutrients ...
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1answer
182 views

Approaches towards a theory of innovation in evolution

Evolutionary biologist Andreas Wagner writes in his book "The Origins of Evolutionary Innovations: A Theory of Transformative Change in Living Systems" (Oxford University Press, 2011): We are ...
2
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2answers
71 views

Infer gene frequency within a species over time

I was reading Karlsson et al. (2014) and I came into this: A selected variant that increases rapidly in frequency in the past ~250,000 years can be detected as an unusual reduction in genetic ...
9
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3answers
140 views

Intuitive explanation for Kin- and Group- selection

It is known from theoretician in the field of kin selection that kin selection (inclusive fitness theory) and group selection are actually two sides of the same coin. In other words, these two ...
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1answer
84 views

Did toads evolve from frogs?

I know frogs still exist but that doesn't mean there wasn't ever a frog population that evolved into toads. Did frogs evolve into toads because their available swamp slowly went away and toads could ...
0
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1answer
22 views

Measuring tumor heterogeneity [closed]

I would like to ask if there's any method (established or not) in order to quantify heterogeneity found in mutations occuring in primary neoplasms and metastatic lesions (either common or private) and ...
3
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0answers
48 views

Is $F_{ST}$ a probability and a correlation coefficient?

$F_{ST}$ is one of the most famous and most important statistics of all of evolutionary biology. Yet, many people misunderstand it or misuse the classical results from the literature on $F_{ST}$ (...
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1answer
43 views

How to compare diversity between different ecosystems?

I've used the Shannon Wiener Diversity Index for a single ecosystem (species as categorical variables). Do you know any alternative indices, especially ones that compare diversity between different ...
2
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1answer
61 views

First life forms to evolve controlled flight

What was the first living organism able to fly in the skies and control their direction , not just Aeroplankton like bacteria and viruses carried by the winds but something like an winged insect or ...
3
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1answer
147 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 ...
6
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1answer
121 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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3answers
190 views

How scientists can be confident that human embryo tail is really a tail?

From Wikipedia: Human embryos have a tail that measures about one-sixth of the size of the embryo itself. As the embryo develops into a fetus, the tail is absorbed by the growing body. How are ...
2
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2answers
500 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 ...
7
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2answers
2k views

Why did the urinary bladder evolve?

Sure it's convenient to decide when to urinate but not essential for survival or reproduction, as I understand. But just convenience is not a drive for evolution. Does the bladder serve any essential ...
0
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0answers
36 views

Brain capacity of Cro-magnon man vs Modern man

Cranial capacity of Cromagnon man was about 1650cc whereas average cranial capacity in modern human is 1450cc. My question is, why during the course of evolution, a reduction in cranial capacity is ...
2
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0answers
43 views

Why were dinosaur skeletons so light compared to mammal skeletons?

I was watching a presentation by Dr. Jessica Theodor [1] who discusses (at 38:10), among other things, the skeletal structure of dinosaurs vs. mammals. "Dinosaurs have way lighter skeletons, which ...
4
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0answers
26 views

How were (many) dinosaurs' brains so small?

Brain size (or its proxy, encephalization quotient) usually varies allometrically with mass -- larger creatures need larger brains to control their larger bodies, apparently. Dinosaurs are popularly ...
5
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1answer
1k views

If oxygen is such a good energy source, why do plants release it?

Why do plants release excess oxygen, rather than consuming it entirely given it is an excellent energy source?
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4answers
7k views

Why would a plant evolve to produce an addictive chemical?

It seems kind of anti-productive in terms of survival for a plant to produce an addictive chemical as that plant will constantly be sought after by animals that ingest it. In this instance, I'm ...