Evolution refers to the observed changes in successive generations of biological organisms due to heritable components (genes and DNA). Charles Darwin proposed a major mechanism of evolution: natural selection.
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How did the activities of protocells become inheritable?
I have learned that first a protocell came to exist and its characteristics came to be passed on by genetic material. So how come genes for all the activities come to incorporate into genetic ...
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Has medical progress stopped human evolution?
We can cure many diseases nowadays, and thus the natural selection is very limited.
Plus, mankind spent the whole beginning of its existence in almost the same hostile environment, and that's where he ...
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What are some examples of scaling laws in biology?
I've seen that metabolic rate scales logarithmically as function of mass for many animals over an extremely large span of parameters. What other scaling laws exist at the individual level?
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Why is a slow worm not considered a snake?
Slow worms are considered lizards as opposed to snakes, both are reptiles. Now I get that there are traits that distinguish them (eye lids, ears ...). But snake species themselves vary already quite a ...
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If Evolution Is In Progress, Why Fight Extinction?
Natural selection is a central dogma of evolution. However, most biologists seem determined to prevent the extinction of the species that have been selected against. Why is this? Preservation of ...
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What is the evolutionary reason behind the fragility of teeth?
Almost all organs in the human body have a rather large threshold within which the organ or tissue is capable of repairing itself using materials supplied by the body, whether it's made from organic ...
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Why do sloths come down from the trees to defecate?
I'm under the impression that most sloths exhibit this behavior, but why? They are slow moving and so have no way of escaping from predators when on the ground. Not to mention the energy they expire ...
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What was behind the evolution of human brain? [closed]
Why did the human brain evolve!?
certainly it was not selective evolution, it seems something inside DNA forced human to evolve through brain
Evolution (or development process of human) is more ...
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Macroevolution vs. microevolution
Where is the line usually drawn between macroevolution and microevolution?
I thought that, although similar processes govern both, the line was at the species level, with macroevolution being changes ...
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Why are there no wheeled animals?
In physics, "almost everything is already discovered, and all that remains is to fill a few unimportant holes." (See Jolly.) Therefore, on Physics SE, people are veering off into different directions: ...
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Lineage selection in plasmid evolution
I've been reading through Paulsson (2002) and I am not sure what he means by "lineage selection" in the second to last section. The paper deals with plasmid replication, and mostly concentrates on the ...
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Structure of fitness landscapes in the NK model
The NK model of rugged fitness landscapes consists of $N$ sites where fitness contribution of each site depends on its state $\{0,1\}$ and is epistatically affected by $K$ other sites. When defining ...
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Are there natural selection experiments that quantitatively agree with theoretical modeling?
Has anyone ever conducted an evolution experiment and quantitatively compared it to theory? For example, has anyone ever put bacteria in a million petri dishes filled with antibiotics and calculated ...
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Is local equilibrium a reasonable assumption for evolutionary processes?
Whenever I look at discussions of fitness landscapes (in particular, Kauffman's NK model) the questions tend to resemble:
The population is at a local equilibrium, but another equilibrium of ...
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The oldest common ancesstor of all human beings
Do all human beings have a single oldest ancestor (a man and a woman), or were there were many ancestors at the same time at different places on earth?
This article sheds some light. Is there another ...
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Reproductive isolation causing evolution
My course book says about reproductive isolation that it does not allow the interbreeding among the individuals of different species. It also says that it is a cause of evolution.
How is this cause ...
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1answer
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Why does the PR form of phytochrome exist?
I know how it gets converted because PR is more stable and when there is neither red or far red light PFR naturally converts to PR. But what is the point of it? If PFR is the biologically active one ...
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What's the Evolutionary Purpose of Religion? [closed]
I would imagine the answer to this question would be that religion tends to cause greater compliance of individuals within society, so it is pro-society. Plus these religions tend to incorporate some ...
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Is it possible to make bacteria vulnerable to antibiotics it's resistant to?
Since bacteria becomes resistant to antibiotics after an unfinished course, is it possible to do anything to be able to get treatment with the same antibiotic again, and reverse the resistance in the ...
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Cyanobacterial photosynthetic oxygen yield
I am somehow not convinced that biotic factors are solely responsible for creating 21% of atmosphere (around 40 million moles of oxygen).
There may be additional issues here. Since cyanobacteria ...
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How did this spider evolve to mimic exactly a human face and arms?
So I came across something terribly amazing today, that is, a video showing this species of peacock-spider, that literally, transforms into a human face waving his arms about.
What could have ...
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How might gene clusters like the lac operon evolve?
The obvious answer for a gene cluster is gene duplication and mutation of one or both genes. But the genes in the lac operon seem not be so functionally/structurally similar (as compared to the Hox ...
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Zero selection in evolution
The evolution is creative because of random-generated solutions and useful because only best solutions are selected. The natural selection not only brings species to perfection but also keeps them ...
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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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What's the Evolutionary Purpose of Hair in Humans (namely the hair that grows on their skin, NOT internal hairs)? [closed]
My guess would be the following four:
Protection from the cold (especially head hair)
UV light protection (especially head hair but hair elsewhere would also protect from UV light in times when ...
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Why do some people find vegetables so repellent when evolutionarily they should find them an attractive and thus tasty food?
Why do certain people (especially kids) find vegetables so "repellent" when evolutionarily they should find them an attractive and thus tasty food?
I ask this question because if Darwin's theory of ...
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Why does sexual selection evolve beautiful features?
First question here. I have a very raw understanding of sexual selection:
Say a group of females of a certain species "likes" some feature of a certain groups of males; by "like" I mean some ...
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Indestructible Super Shrimp
How are shrimp and other animals able to not be crushed by the 1000x greater pressure at the bottom on the Mariana trench?
Wiki says the trench is home to "large living creatures such as a sole or ...
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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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Why aren't antheridia and archegonia touching?
Antheridia and archegonia are the two male and female gametangia, respectively, and they are found in bryophytes. To cause fertilization, usually a thin film of water must be present for the sperm ...
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When does weak selection produce qualitatively different results from strong selection?
In evolutionary game theory, it is typical to model organisms as having a base fitness that is modified slightly by the game interaction. The ratio of the game effect versus the base fitness ...
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What is the difference between a circular and a cat's-eye pupil?
I've been to local zoo the other day and one lizard caught my attention: its pupils are circular, which, I thought, is not usual for reptiles. Turns out it is, but now I can't find any explanation on ...
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Is there any evolutionary/physiological advantage to multi-lateral symmetry?
Just wondering ; I get the impression a large number of multicellular organisms are multi-lateral in their physical structure. Why would evolution/mutation have retained multi-lateral symmetry in an ...
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Plants without bacteria? is it theoretically possible?
I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...
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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 ...
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Can this theory on the evolution of human appearance be flawed?
This is what a friend of mine said:
When there's human offspring, it will look a rough 'medium' between
the two parents, with it sharing features from the two. well if the
offspring of one set ...
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Do plant-animal cross races exist?
Plants and animals have the following distinct properties:
Plants live from solar energy by photosynthesis, they use solar energy to make sugar and oxygen out of carbon dioxide, which gives them ...
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Why doesn't recombination occur in male Drosophila?
"Males do not show meiotic recombination, facilitating genetic studies."
For a while I have known that this phenomenon occurs, this quote comes from the Wikipedia page on Drosophila melanogaster, ...
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What are some alternatives to Charles Darwin evolution except creationism? [closed]
What are alternatives to Charles Darwin evolution except creationism?
Is there any "hypothesis" except evolution and creationism or there is none?
Btw. I consider things like some proto-building ...
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How does natural selection favour large body mass and size (or so it seems)
I was walking through a park this afternoon and observed a few birds having fun flying around and it got me thinking why would natural selection favour birds with flesh at all if it hinders their ...
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Is there an “Adam and Eve” for each new trait during (not just human) evolution? [duplicate]
Do new beneficial mutation evolve simultaneously and independently with several individuals of the same specie or only with one specimen who then transfers it to all of the specie?
In other words, ...
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A question regarding evolution
I'm not a biologist so bear with me. I know that the DNA molecule carries extremely large amounts of information. If the process of evolution is driven by completely random process .I think about it ...
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Why did animals evolve genders? [duplicate]
The majority of animals have two genders, and both are needed in reproduction. It seems like it would be more advantageous for creatures to be hermaphrodites, since they could mate with any member of ...
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Which sex has higher variance of reproductive rate in modern societies - male or females?
Who has a more varied reproduction rate in modern western societies - men or women? The average rate is the same of course, but I wonder which sex have higher variance - higher variance means that ...
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why do organisms die [duplicate]
Possible Duplicate:
What is the evolutionary advantage of death?
From an evolution perspective, it makes more sense that the organisms which live longer, obviously, survive longer.
So why ...
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How can a three-base codon evolve from a two-base codon?
Inspired by this question among others.
It's widely suggested that the current 3-base codon system of encoding protein sequences in DNA evolved from an earlier 2-base codon system. This makes sense ...
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Why do some animals have 8 Limbs (e.g. Spiders, Octopuses)?
Octopuses have 8 tentacles, spiders have 8 legs.
Is there something special about 8? It seems like an animal that needs 360° mobility has 8 legs.
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Mathematical Modelling of Natural Selection
I'm a math undergrad looking for some papers on modelling the process of natural selection. The only paper I've been able to find is by the pre-eminent mathematician Herbert Wilf from 2010,
There's ...
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Extraretinal photoreception in mammals? [duplicate]
A Finnish firm Valkee sells light-ear-plugs against thing such as jetlag. I asked a researcher in Aalto university how do they really work and he responded ...
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Why people like to see pornographic scenes, but do not feel the same about eating scenes?
This question may seem funny, but I think biology must have good answers.
I think no more explanation is needed.
I really thought about this and searched for an answer, but there is nothing yet.
If ...
