Ilmari Karonen
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Is the theory of evolution being disproved by bats?
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44 votes

Take a look at this little fellow: It's a flying squirrel — a shy little nocturnal rodent which lives in trees and, despite its name, does not actually fly. It does, however, have a skin ...

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Why does vaccine development take so long?
40 votes

While the existing answers are great and cover a lot of the difficulties in vaccine development, I feel that they fail to address (or at least sufficiently emphasize) the fundamental misconception at ...

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Is the "Great Pacific Garbage Patch" beneficial for marine wildlife?
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38 votes

There are very few things in the world that aren't beneficial to some lifeform. Even if you were to, say, spill a mixture of persistent broad-spectrum poisons on an area that killed off 99.9% of all ...

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Why are organs not harvested from deceased cancer patients?
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24 votes

On of the main reasons why cancers are normally not transmissible between different people is basically the same reason as why organ transplants are difficult: histocompatibility. Every human cell ...

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Why do only two sexes exist for animals?
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22 votes

To get a non-circular answer to why humans and other mammals have only two sexes, it's helpful to take a look at our evolutionary history. While mammals possess several adaptations to a terrestrial ...

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What is the difference between the evolution of fins in whales and fish?
13 votes

I agree with you that the question is ambiguous, and also that the most sensible answer would be C. However, one could make a more or less reasonable argument in favor of several other answers, too. ...

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How is the fluoride in toothpaste absorbed?
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13 votes

The chemical mechanism by which fluoride protects teeth is the remineralization of hydroxyapatite $\ce{Ca5(PO4)3(OH)}$ in the tooth enamel into fluorapatite $\ce{Ca5(PO4)3F}$: $$\ce{Ca5(PO4)3(OH) \ (...

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How do trees manage to grow equally in all directions?
11 votes

They don't always. For example, this apple tree grows just outside my window: So far, it hasn't fallen over yet. The reason it grows that way is because all the light is coming from the right side ...

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Why are certain baby (water)fowl yellow?
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9 votes

Wild ducklings, like these baby Mallard ducks, are in fact typically only partly yellow: Photo by TheBrockenInaGlory via Wikimedia Commons, used under the CC-By-SA 3.0 license. While I'm no expert, ...

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Why is selfishness the 'obvious' strategy?
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9 votes

It basically comes down to a question of the unit of selection. From the common viewpoint, in which natural selection is seen as acting on individual organisms, it's almost a tautology that the ...

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Shortest strings not present in the human genome
8 votes

The human genome contains less than 416 base pairs, so, even after including a factor of 2 for the two strands and another to allow for some genetic variation, there must certainly exist some 17-base ...

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What advantage would the initial 'donor' in horizontal gene transfer by conjugation have received?
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8 votes

The donor bacterium, viewed as a unit, may well gain no advantage from sharing its genes. The genes that are shared, however, may gain a very substantial reproductive advantage from being able to ...

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How do baby animals that primarily subsist on cellulose get their initial gut flora?
8 votes

I don't know about ruminants, but baby rabbits (and presumably other lagomorphs) apparently acquire the necessary intestinal flora by consuming their mother's cecotropes.[1] [1] Johnson-Delaney, C.A. ...

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Can species back-evolve?
8 votes

There are several strains of mutant cells from humans, mice and various other species that have found themselves a niche as single-celled organisms living in lab dishes, and seem to be thriving there. ...

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Why is 'Grudger' an evolutionary stable strategy?
7 votes

In an infinite, well mixed population with single pairwise encounters, Grudger is indeed not an ESS. In fact, as you correctly note, in such a model the Grudger and Sucker strategies are ...

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Do probiotics survive digestion?
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7 votes

Apparently, some do and some don't. I just tried searching for yogurt lactobacillus survival on Google, and the first hit I got was an article titled "Survival of yogurt-containing organisms and ...

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Weighing 2 vertical halves of the human body
6 votes

Humans, like all vertebrates, belong in subregnum bilateria, a broad class of animals whose characteristic trait is having a bilaterally symmetric body plan at least in some of their life stages. The ...

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RNA or ribosome, which one moves during translation?
6 votes

The ribosome moves relative to the mRNA by, in effect, pulling itself along it. If both the ribosome and the mRNA are freely floating and not attached to anything else (as in jp89's answer), the ...

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How would constantly growing nails have aided early human?
4 votes

I can't say anything for sure (and, with questions like this, it's rare that anyone can), but my guess would be that human nails grow constantly for the same reason as the (analogous) claws of most ...

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Is Natural Selection like a Copy Editor?
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3 votes

Evolution, in the Darwinian sense, can be broadly described as the interaction of three processes: inheritance, mutation and selection. Of those three processes, mutation is the one that produces ...

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HSL Lightness vs Eye sensitivity
1 votes

No, the L axis in the HSL color space does not really correspond to lightness as perceived by the human eye, except in the very crudest sense that, for given values of the H and S components, ...

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Is DNA mutation locally energetically stabilizing the DNA molecule
1 votes

The reaction kinetics of DNA mutations are complicated by the fact that the DNA doesn't exist in isolation, and in fact is actively processed and maintained by the cellular machinery. For example, as ...

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