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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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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99 views
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 have humans evolved much more quickly than other animals?
Humans have, in a relatively short amount of time, evolved from apes on the African plains to upright brainiacs with nukes, computers, and space travel.
Meanwhile, a lion is still a lion and a ...
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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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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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Why are not all species hermaphrodites?
If a hermaphrodite animal (like slug, snail, etc) finds a partner they can mate immediately.
If another animal with "normal" reproduction (lets say a mouse) finds a partner they can only mate if they ...
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Is there any recent evidence for the aquatic ape theory of human evolution?
aquatic ape theory suggests that many features that distinguish humans from their nearest evolutionary relatives emerged because the ancestors of humans underwent a period when they were adapting to ...
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3answers
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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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4answers
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What was the reason for some plant and animals to become giant in course of evolution?
The dinosaurs, mammoths, giant plants etc are known to be bigger than modern animals. I wonder why they had been lived and why they are not living now? I really don't know much but is it something ...
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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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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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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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Short-term Lamarckism in asexual single cell organisms
I was reading through the Karr et al. (2012) whole-cell computational model. One of the things they did was to induce single-gene disruptions in their model. They observed several to be fatal, but:
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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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Why does human facial and head hair continue to grow?
Many people can grow extremely long head hair and facial hair. Are there evolutionary theories as to why this is the case? It seems like having long hair could be a disadvantage, and extremely long ...
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1answer
51 views
Interlocus Contest Evolution means suicide?
I was reading Matt Ridley's "Genome" book. I am trying to understand the Interlocus Contest Evolution in his X-Y chapter. I do not understand why the X and Y chromosome would want to kill each other. ...
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Is the theory of evolution being disproved by bats?
For some species the Darwin's theory evolution makes perfect sense. I can easily imagine how, for example, the giraffe has evolved to its current appearance: the natural selection was favoring ...
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2answers
117 views
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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3answers
399 views
What is the evolutionary advantage of death?
I know death and cancer doesn't hurt humans' reproductive success. It's not helping either.
Why do we die? Why dying humans (all of us) are common? What's the point of dying?
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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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3answers
309 views
What is meant in biology by the term “evolved”?
A student asked me this the other day and I thought that I would ask it again here. If one organism is said to be "more evolved" than another, what exactly does this mean?
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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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4answers
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What evolutionary reason is there for having the urinary duct and reproductive organs so close together?
As the old joke goes, "God must have been a civil engineer. Who else would put a waste facility straight through a recreational area?"
But maybe it wasn't God. Is there any evolutionary reason (or ...
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4answers
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Why 20 amino acids instead of 64?
This question got me thinking about amino acids and the ambiguity in the genetic code. With 4 nucleotides in RNA and 3 per codon, there are 64 codons. However, these 64 codons only code for 20 amino ...
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2answers
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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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Human evolution: Where *exactly* did the first human come from, whose parents were not?
Layman here. So I have never really quite understood this facet of human evolution, (or any other for that matter), in that, I understand the evolutionary process, but I get lost on the 'border' ...
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2answers
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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 ...
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4answers
287 views
Refutation of Darwin's Random Evolution Theory
I saw this refutation online of Darwin's Random Evolution Theory and cannot see any holes with the logic. Can anyone crack this simple refutation?
Refutation of the Theory of Random Evolution
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2answers
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Are humans still competing in the same way now that the first life forms did?
I'm not sure if this is actually a philosophical question, but I was reading a timeline of life on earth and I came to this:
4500-3500 Ma The earliest life appears, possibly at Alkaline vents
...
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139 views
Why have humans evolved conciousness?
Why did humans/animals evolve to become self-aware of their own thoughts. That is, why don't humans act and compute like a machine, or walking zombie. In my mind, such creatures would still be as ...
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Why Is Most Life Symmetrical Externally But Not Internally?
Mammals, reptiles, arachnids, insects, etc are all as far as I am aware symmetrical in appearance.
Take a human for instance, make a line from the top of our head right down the middle. However, ...
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Evolutionary explanation to why we have such large memory capacities?
The scientific consensus is that no one ever fills up their memory capacity by learning facts and so on, even in the information age. My question is therefore, is there an evolutionary reason as to ...
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Why are eggs “egg” shaped?
Is there a reason as to why chickens lay "egg" shaped eggs, as opposed to spherically shaped eggs (or a random shape)? <--- Main Question
For extra points (actually just to add more words in ...
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Evolution in 37 years, is it possible?
I am confused, can evolution ( speciation ) really occur in such a short time ?
In 1971, biologists moved five adult pairs of Italian wall lizards from their home island of Pod Kopiste, in the ...
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How did the huge dinosaurs cope with gravity and loads on bones, etc.?
It's very costly to be a huge animal. Your mass grows in cube when you scale up, but you still only have two/four legs to support the same weight. This increases the pressure that your body needs to ...
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Historical recovery from mass extinction events
Is there a way to generally characterize how species "regrew" after the various mass extinction events happening periodically from 450 Ma to 65 Ma. Would the surviving species just start back where ...
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Would ovoviparous to viviparous mutation have been gradual? How would that work?
It seems unlikely that an ovoviparous ancestor of mammals long ago could have had a viviparous offspring in a sharp one-generation dividing line, but what would be the gradual steps between egg birth ...
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Chromosome 2 fusion?
I read this article by Jeffrey Tomkins and Jerry Bergman claiming to debunk chromosome 2 fusion. Is there anything wrong with these conclusions?
" 1.The reputed fusion site is located in a ...
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What is the evolutionary rationale for palm sweating?
Sweaty palms seems to be a reaction to stress, anxiety, etc. For our forest-inhabiting primate ancestors sweaty palms could cause unwanted side-effects such as slipping off tree branches under ...
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Why is Galapagos island so special?
I am not a biologist so the question may be very stupid. I have no idea. Why did Darwin formulate his theory of evolution just after his visit to the Galapagos island? Why is it so special from the ...
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4answers
459 views
Which came first: The Chicken or the Egg? [closed]
Has there been any serious scientific inquiries into answering this age old question?
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How can I compare rates of evolution for two sets of proteins?
I have a list of candidate proteins as the result of my analysis. I am now trying to find various characteristics that they have in common. One of the things I would like to check is if my candidates ...
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Resources for learning Anthropology [closed]
I'm a programmer by profession and passion. I've been interested in biology, especially regarding evolution in school. Now I would like to learn Anthropology in my free time. Can you point me to some ...
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Colonial Cells Demonstrating Cell Specialization
Are there any living examples of cellular colonies demonstrating very primitive cellular specialization? If so, what do we know about how they assimilate? How independent are the individual cells ...
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356 views
What is the modern state of the theory of evolution?
When I studied biology at my medical school we used to learn things about a century old: the famous Darwin's voyage on "Beagle" to the Galapagos Islands, the classical triad of his Theory of ...
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What measures are commonly used for the complexity of an organism?
I'm aware of measures like number of distinct cell types being used as a measurement of complexity in biology, for example in the G-value paradox. But this doesn't really help for unicellular ...
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Is there any complex organism that is both autotroph and heterotroph?
Possibility also include "adaptation mode" if such exist. I don't discern whether autotrophic/heterotrophic part play only minor role either.
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Good book on Origin of Life [closed]
What is a book that goes into reasonable detail (but isn't textbook-level technical) about the origin of earth and in particular the origin of life on earth? Something intended for a broad audience, ...
