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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What's the mechanism or structure responsible for new species genetic code generation?

I always had this question in mind. I think, If humans find answer to it then we can trigger the next evolution of human specie. What is the mechanism or structure responsible for evolution ? I don't ...
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0answers
25 views

Why plants and animals are so different even though they come from the same ancestors?

All the documentaries I have watched, books I have read so far on the starting of life on earth only talk about animals. The very first life form on earth was bacteria. Then evolution took us this ...
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2answers
52 views

Are human beings evolved to eat meat? [duplicate]

I know humans can cook, and prepare almost anything, but are humans specifically adapted to eat meat. One of my doubts humans are not particularly well adapted to eat meat because they lack canine ...
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0answers
30 views

Escaping resource limitations during tumor evolution

In their discussion of the importance of r- and K-selection on tumors, Aktipis et al. (2013; figure 3) provide the following illustration of a hypothetical cancer growth curve: In it, you can see ...
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0answers
3 views

How to incorporate intraspecific variation in discrete characters in comparative analyzes?

I'd like to run a multivariate analysis (Pavoine et al. 2011) that aims to disentagle the effect of environmental gradients on traits, considering its autocorrelation with phylogeny and space. It uses ...
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0answers
108 views

Why did multicellular organisms evolve when a single cell can survive on its own? [duplicate]

Since unicellular organisms can survive, why would there be evolution of multicellular organisms?
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2answers
47 views

Crossing over and exon shuffling?

Campbell Biology 10e, in discussing the functions of introns, writes: The presence of introns in a gene may facilitate the evolution of new and potentially beneficial proteins as a result of a ...
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1answer
39 views

Why did eukaryotic cells develop? [closed]

If eukaryotic cells can survive in extreme conditions, then why are their still prokaryotic organisms?
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5answers
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If evolution is not about improvement, why is there so much improvement?

In my last question I asked why we don't see improvement in artificial life simulations of evolution. It seems I had fallen for a common misconception, that evolution was about improvement. One ...
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0answers
42 views

Do animals demonstrate target practice (i.e., playful accuracy behavior)?

Do animals demonstrate any sort of accuracy-motivated play? (please provide examples!) Consider most human sports and related hobbies. Most share the common goal of hitting a target or being ...
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1answer
72 views

Why do simplier plants live in water? [closed]

Lower plants such like algae are considered to be simplier organisms, than those plants that live in water. Why had'nt they evolved as much as the land kind?
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5answers
2k views

Why are there species instead of a continuum of various animals?

As I understand it, various animal traits have to evolve gradually, but what happens to the species that are "neither here nor there"? To put it differently, if a species evolved from another, it did ...
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1answer
66 views

Evolution of dominance of alleles

Can someone tell me where can I find detailed text about mechanisms of evolution of dominance? Or, if it is possible, I would be grateful if someone will tell me about them here.
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1answer
127 views

The replicator equation vs the Lotka-Volterra equation

Background The replicator equation with $n$ strategies is given by the differential equation: \begin{equation} \dot x_{i} = x_{i} \left( \sum_{j=1}^{n} a_{ij}x_{j} - \phi \right) \qquad i = 1, ...
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0answers
21 views

Does the bending of a tree's trunk in the wind stimulate and strengthen root growth?

Recently Southern California experienced extreme wind velocities and afterwards the news reported over 300 trees had fallen in San Diego County. I had either heard or read somewhere that the action of ...
3
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1answer
48 views

What came first? The DNA or the DNA polymerases?

I know this sounds a lot like chicken and egg question and while the latter has an answer, I am intrigued about the former. A modified form of the question would be, in the course of abiogenesis, ...
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1answer
140 views

Examples of animals with 12-28 legs?

Many commonly known animals' limbs usually number between 0 and 10. For example, a non-exhaustive list: snakes have 0 Members of Bipedidae have 2 legs. Birds and humans have 2 legs (but 4 limbs) ...
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1answer
37 views

Is it known how human sweat glands evolved?

If human descends from apes than probably we lost our hair. Perhaps in the age of homo erectus we lost our hairs and began transpiring through our skin with sweat glands. But how did these glands ...
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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
71 views

Evidence of species transitions [closed]

I had a debate with a person who believes in some kind of creativism, let's call it that way. And in the middle of the "debate", an interesting question popped up. What are evidences of ...
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1answer
36 views

Was the frequency of mutations more during primitive earth due to radioactivity?

Primitive earth was more radioactive (or was it really?) according to radiometric analysis of C14 which suddenly appeared at 4250 million years in the Hadeon eon. Is it possible that ancient high ...
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1answer
63 views

Why does the proportion of transposable elements vary so much across species?

Intuitively, transposable elements (TEs) are harmful as they may cause genome instability. However, some people argue that TEs are also sources of variations, especially regulatory sequences[1]. If ...
2
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1answer
92 views

Mutation-drift equilibrium and among loci variance in heterozygosity

At mutation-drift balance, the increased heterozygosity brought by new mutations is exactly equal to the loss of heterozygosity due to genetic drift. At equilibrium, the expected heterozygosity for a ...
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1answer
92 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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0answers
26 views

The evolution of sleep [duplicate]

Are there evolutionary theories as to why we (and most animals) sleep? Some claimed functions of sleep include: restoration, waste clearance, memory processing, etc. But unless we understand why ...
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0answers
43 views

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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3answers
2k views

Why did abiogenesis only happen once?

If the "primordial soup" theory of abiogenesis is to be believed, self-reproducing organisms spontaneously arose on Earth at least 3.5 billion years ago, surprisingly soon after the Earth cooled down ...
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1answer
92 views

Selection Pressure on Orca Whale Coloration

What is the proposed selection pressure that leads to the distinctive coloration of Orca whales? I can find nothing in the literature.
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7answers
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Why does evolution not make our life longer?

Why does evolution not make life longer for humans or any other species?
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2answers
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Why are the Galápagos islands so special?

Why did Darwin formulate his theory of evolution just after his visit to the Galápagos islands? Why were they so special from an evolutionary point of view?
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1answer
103 views

Have scientists ever produce a new species in laboratory by means of natural selection?

I was wondering, if scientists ever produce a more complex species from a less complex species by means of natural selection? I imagine something like, bacteria which can't photosynthesis and oxygen ...
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1answer
139 views

Can someone help me analyze this article? [closed]

I need to read this article — "Beyond the rainbow" by Marie-Claire Koschowitz et al., for an exam. Following are some questions for which I could not figure the answer out after reading. 1) Why ...
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1answer
46 views

How to understand Aposematism and Batesian mimicry

EDIT I want to understand the reason for intense animal colors. I.e. I don't want to understand the variety of the colors, just the intensity. The Wikipedia page for Cethosia biblis says, the intense ...
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1answer
59 views

Does evolution thinks? [closed]

I understand evolution as survival of the fittest rule , where its the nature and surroundings that shapes the life by extinction of species which are not fit to survive the nature at that period. To ...
7
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1answer
183 views

What is most ancestral: isogamy or anisogamy?

Sexual reproduction can be feasible with anisogamy (gametes of different sizes i.e. genders) or isogamy (gametes of same size i.e. mating types) or with undifferentiated gametes (i.e. true random ...
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2answers
199 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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229 views

Can diploidy evolve in absence of sexual reproduction?

Theoretical question Can diploidy (or polyploidy) evolve from a haploid lineage in the absence of sexual reproduction ? For what theoretical reason? How can such evolution take place? Empirical ...
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1answer
36 views

What contribute to the variation of protein sequence across different species and how do they influence?

What contribute to the variation of protein sequence across different species (e.g. phenotype, environment, evolutionary pressure) and how do those factors contribute to the variation? I have tried ...
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0answers
18 views

Why is marginal reconstruction “more correct” than joint reconstruction in some cases?

When reconstructing the ancestral states on a phylogenetic tree given the states at the tips, there are a number of methods for performing the reconstruction. This question is about marginal and joint ...
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2answers
188 views

Why even if all requirements for natural selection are met, it may not happen?

In the book written by John Endler Natural Selection in the Wild p. 4 it says that even if condition a, b and c are met, evolution by natural selection might occur, [...] , but not necessarily, ...
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1answer
159 views

What are the minimum conditions required for “open-ended evolution”?

According to a paper about artificial life systems, the following four conditions have to be fulfilled for "open-ended evolution": Condition 1: A rule should be enforced that individuals must ...
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6answers
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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 ...
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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. ...
3
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4answers
112 views

Is an egg classified based on the species inside it, or by the species that laid it?

Basically what I'm asking is if an animal of species x were to lay an egg, and the animal inside that egg happened to be the first member of a genetically new ...
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2answers
78 views

Are there any predators without camouflage?

Are there any predators that don't use camouflage?
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1answer
59 views

Is there a formal definition of signature of natural selection?

I’ve searched for a definition of signature of natural selection. Unfortunately, I haven’t found any formal definition of it. The signature of positive selection ...
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4answers
2k views

How can homosexuality evolve despite natural selection?

I would imagine that the answer to this question would be population control, especially since even if one sibling is homosexual this does not necessarily mean that the other siblings will be too.
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3answers
266 views

Symmetry of species [duplicate]

I've got a silly question, sorry for that. I know, that we probably have no the right answer and the current answer could be "that's evolution, external conditions". I'd like to speculate, why most of ...
5
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2answers
80 views

Evolution of spider webs?

Web making seems like a fairly complex behavior built from a pretty strong material. So how exactly did it evolve? Do we have any clues about what kind of features/behaviors preceded web making and ...
5
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1answer
95 views

How does the value of K determine number of local optima in NK model?

BACKGROUND The NK model of fitness landscape considers N states which can interact with K other states. For example N is the total number of genes in a haploid genome and K is the number of other ...