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Questions tagged [evolution]

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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What does (G+) (G++) in terms of male mutation rate and male-heterogametic XY-system?

What's the expression for $\alpha_m$ in case of male-heterogametic XY systems (G+)? Derive the corresponding $\alpha_m$ expression of for (sic) male-heterogametic XY systems (G++) I have ...
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Why does the seed of the coconut tree have a liquid in it?

What is the purpose of water in the coconut seed? The reason I ask this is that I was reading about coconut water and all the benefits it has for us Humans. But why does the tree put a liquid in the ...
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Where did Neanderthals and Denisovan Man come from?

Neanderthals, Denisovans and our species (Homo sapiens) are commonly cited as closely related subspecies, even interbreeding with each other. Yet our species theoretically didn't migrate out of Africa ...
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Do primates have genetic predisposition to dominance hierarchies [on hold]

I’m looking for some evidence to prove (or disprove) that primates are genetically predisposed to dominance hierarchies. I would appreciate any pointers/references to scientific literature. PS: The ...
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1answer
211 views

Up to date, extensive documentary about dinosaurs? [on hold]

I just finished reading the Wikipedia page about dinosaurs, and I very much enjoyed it. I knew that much of what I learned in the 80's as a child is (and was) incorrect, and now that I am a parent, I ...
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65 views

Has human skin pigmentation adaptation and evolution ceased?

Before asking this question read Why human skin colour disprove natural selection? Does darker skin color make it easier to live under sun? though neither posed the same question or provide the ...
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3answers
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Can domestic breeding be considered evolution?

Domestic breeding of animals (and plants) by humans seems to match some of the definitions of evolution I have been able to find: "a process that results in heritable changes in a population spread ...
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3answers
92 views

Evolution question on speciation? Really confusing!

Okay, my teacher assigned this homework question, but nothing like this was ever given in our textbook. Suppose that a type of tree tends to speciate over 10 million years and a species of fly tends ...
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Question regarding when it's a homoplasy in a phylogenetic tree

If you have 2 organisms that both come directly from the same common ancestor on a phylogenetic tree, and that common ancestor does not have trait "x", is it possible for both of its direct ...
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50 views

Why the position of facial organs is the same for almost all animals on Earth?

I was questioning myself on why the position of facial organs (eyes, nose, mouth) is the same for almost all animals on Earth ? Is it because of a common ancestor in evolutionary history ? We don't ...
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1answer
43 views

Animal with “advantageous” trait in a environment where the trait is never utilized (high cold tolerance in mild climate) - natural selection occur?

If you were to put an animal with a certain type of seemingly advantageous "trait" into an environment where the trait was not necessarily needed, ex: Putting an animal with a high tolerance for cold ...
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Contructing phylogeny from an asymmetric distance matrix?

Is there any method for constructing a phylogenetic tree from a distance matrix which is not symmetric (i.e. the distance from A to be is not the same as the distance from B to A)? The distances I ...
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Tetrapod Evolution [closed]

It has been known for a number of years that there have been tetrapod tracks predating Stegocepgalians by tens of millions of years at the least, and now this article has put forward the claim the ...
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1answer
45 views

Why is the ability to drink salt water so rare in land-animals?

Apparently, some species are capable of drinking salt water, like the sea lion and otter. But given how rare fresh water is, and how abundant salt water is, why have more land animals not evolved to ...
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What is the evolutionary context of bitter taste?

Why do we react to bitter taste the way we do, and how did we acquire this function during our evolution as a species? Could it be that a strong bitter taste is predominantly associated with ...
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What is a neutral and non neutral polymorphism? [on hold]

What is a neutral and non neutral polymorphism? What is a neutral and non neutral polymorphism? What is a neutral and non neutral polymorphism?
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1answer
26 views

The Hawk-Dove game: why is the average payoff half of the difference between reward and cost?

My question is about the well known Hawk-Dove model used in game theory. It concerns two strategies: the Hawk, which always fights the opponent, and the Dove, which does not fight and will either ...
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6answers
4k 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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What ecological niche do disk shaped fish exploit?

I looked up "Early Triassic" to get a sense of what that meant and I ended up on this image of marine life at the time. I noticed some disk shaped fish (#8 in the picture: Bobasatrania (durophagous ...
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How does DNA code for the actual *shape* of individual body parts/areas (NOT segments or Hox genes)?

Just to save the trouble - I am not asking for general information on how DNA codes for proteins and definitely not how Hox genes work. I have a very good understanding of the evolutionary process and ...
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0answers
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What are haplotype blocks and what is the effect of hybridization on these?

In this PDF, there is a quick definition of haplotype blocks. A haplotype block is a set of closely linked alleles/markers on a chromosome that, over evolutionary time, tend to be inherited ...
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1answer
392 views

Is abiogenesis possible today?

Life on earth started about 3.5 billion years ago. I would assume abiogenesis happened because the conditions were right. Would the current earth conditions allow for new abiogenesis and completely ...
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2answers
1k views

Online phylogenetic tree of human lineages

I am looking for a source of information about the diversity of human lineages and their relationships. With a quick google search it is easy to find this type of tree A perfect online resource ...
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1answer
112 views

Why do some animals have beards?

Why do some animals such as some Goats, Ibex, Orangutan etc, have long well-shaped beard like men?
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Where does Darwin state his “principle of multiple utility”?

I have never heard of Darwin's 'principle of multiple utility', but several papers refer to it. For example, from Darwin at the molecular scale: selection and variance in electron tunnelling proteins ...
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2answers
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Can I change the genetics of a group of plants naturally?

I have been thinking about introducing all sorts of types to certain environments where the plants will have to adjust to survive. For example having a dark area with one light source right next to ...
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4answers
633 views

Is natural selection a tautology, and therefore not truly falsifiable?

I've heard the argument from a lot of creationists that all the evidence for natural selection (and by extension, evolution) in general is worthless because natural selection is so flexible that it ...
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0answers
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Were there any terrestrial species in the ancestry of all crustaceans?

To the exception of woodlice, Crustaceans live in aquatic (marine or freshwater) environments. Crustaceans are arthropods which is an immensely diverse taxon. Many arthropods live in terrestrial ...
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2answers
49 views

Would prehistoric humans have been considered negroid or australoid by modern standards? [closed]

What are your thoughts about this? For myself I think that the subject statement is rather obvious isn’t it, since Africans, & especially Australian Aboriginals, have the most archaic features &...
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1answer
45 views

Theoretical Rules Governing Life in the Universe [closed]

Obviously, no one can know what life on another planet would look like until we discover such life. However, scientists have speculated that (if I'm not mistaken) all living things must be carbon-...
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1answer
32 views

More general term than “adaptation”

The Wikipedia article about adaptation states: Adaptation differs from flexibility, acclimatization, and learning. What is a more general term than adaptation? For example, is there an umbrella ...
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1answer
43 views

How much of human's behaviors and preference can be explained by evolution? [closed]

I'm talking about things like the tendency to feel sleepy after eating, avoidance of excrements, general preference for sweet foods, etc. Do all those characteristics have biological or evolutionary ...
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3answers
166 views

Why did a lot of common insects evolve such a thin waist?

Something that doesn't quite make sense to me is why lots of insects like ants, bees and wasps have a such a small petiole when it connects many major organs to the rest of their body from a suddenly ...
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Is there a measure for degree of reticulation in a phylogenetic network?

When working with phylogenetic networks, how does one talk about reticulate (i.e., web-like) the branches are? Is there a standard measure of this?
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When we talk of functional macromolecules (e.g. proteins as enzymes, hormones, receptors, antibodies etc), towards what are they evolving?�

Actually this is a question which is given in a book and to be honest,it has baffled me.I'm not so much well versed with molecular evolution so my guess would be,say some sort of enzyme which could ...
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2answers
933 views

What preceded ATP synthase?

ATP Synthase is ubiquitous throughout life on earth and so most probably evolved within the last universal common ancestor (LUCA) before that lineage diversified into the various kingdoms of life. ...
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1answer
33 views

If mammals evolved to be nocturnal, then how did we get so staunchly diurnal in such short time?

Much of human health revolves around sleeping well through the night. We know about circadian and body temperature rhythms which make us sleepy at night, peak melatonin production in the middle of ...
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1answer
120 views

Why aren't leaves black?

I s'pose this is a variant of the age-old question, "Why are leaves green?" It's fairly easy to ask teh internets and find plenty of answers for that one. I have a different but related question: ...
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Why do some foods do not taste good when eaten together that eaten separately would taste great

The way I understand it, 'good tasting food' is evolutionary concept e.g to be able to distinguish between high nutritional value foods and ones that have no nutritional value whatsoever. So if well-...
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7answers
11k views

Is evolution a fact? [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 ...
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18 views

Do four-leaf clovers have some disadvantage in reproduction?

As far as I understand, four-leaf clovers are caused by genetics, so when reproducing, they should produce four-leaved children. I haven't found any disadvantages of four-lead clovers (e.g., ...
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2answers
62 views

How do mutations with very little fitness benefit get fixed?

I have one little issue with evolutionary theory that I have not been able to understand. Suppose genetic mutations happen from generation to generation. Nevertheless, from one generation to the next ...
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2answers
46 views

Does low gravity exposure to early stages of human fetus have potential to unloc unused genetic information from earlier stages of evolution?

The title seems quite self explanatory but let me elaborate. New mutations do take a very long time and many generations to occure in the genetic code. But our genetic code already holds all the ...
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1answer
44 views

What created the first ribosome

If a ribosome is made of protein, yet is used in protein sysnthesis, what created the first ribosome? What created the ribosomal RNA?
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1answer
33 views

Balancing selection vs introgression?

Balancing selection can maintain polymorphisms in natural populations for extended periods of evolutionary time. However, in this paper, Dannemann et al. 2016 identify three archaic haplotypes in the ...
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If mutations are random, why was there just one kind of finches on every Galapagos island? [on hold]

When Darwin was observing the Galapagos finches he noticed that there was a different kind on each island. The biggest difference was in their beaks. Darwin concluded that the birds had evolved and ...
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1answer
1k views

What is the evidence that plants and animals had a common ancestor?

According to the theory of evolution (which I don't dispute), plants and animals evolved from a common ancestor, probably a eukaryote. I'd like to know how we know that to be true. Specifically how ...
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2answers
19k views

Why is the heart not in the middle of the body?

All mammals that I can think of have a high degree of bilateral symmetry (In fact, almost every animal I can think of is like this). So why is the human heart not exactly in the middle of the body? ...
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4answers
235 views

What did the evolution of multicellular animals look like?

What did the evolution of multicellular animals look like? Aspects of this question include: (1) Are there any living organisms that might be helpful in visualizing "transitional forms" between ...
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25 views

Convergence compared to genetic distance

Is there an information (preferably in the form of a chart, though anything will do) comparing convergent evolution to how closely related the 2 species are on the tree of life. My searches for ...