Recent comments in /f/askscience

QristopherQuixote t1_j9as2p5 wrote

The water might be safer if the xrays damage or kill bacteria present in the water or on the bottle. Water is unaffected by Xray radiation.

With respect to the materials, xrays don't modify metals. Xrays over time will change plastic polymers, but the amount, duration of exposure, and intensity are more than a medical xray. Multiple forms of radiation including UV light will modify or break polymer bonds plastic over time. This is why plastic tends to "bleach" in the sun and turn white and powdery as they degrade. Bury plastic underground and it will last a very very long time.

I can't see how an xray would do anything to a water bottle that would affect its safety.

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KauaiCat t1_j9aqcud wrote

They have done studies which indicate different individuals are more/less susceptible to certain viruses based on genetics. For example, some studies have indicated that blood type makes people more or less susceptible. As an example, type O might be less susceptible to Covid, but more susceptible to norovirus.

I think it would be interesting if this turned out to be true for something like blood type where individuals may express one type, but may also carry genes for other types.

Having different genes in the gene pool would allow some members of the group to survive a certain pathogen because they were less susceptible because they expressed that gene(s) while carrying the gene(s) which would allow for less susceptibility to other viruses. This would allow the survivors to repopulate with the full gene package.

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mailboxfacehugs t1_j9annqs wrote

So, in a way, on an atomic level I am always choosing the path of least resistance?

Now I’ll prove just how wrong my therapist’s “oppositional defiance” diagnosis was!

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Mdork_universe t1_j9ani6p wrote

Evolution never really stops. Alleles of genes mix in every generation in sexual reproduction. If the organism is well adapted to one or more environments, the resulting mutations in offspring create little change. Once the environment changes—which is pretty much a guarantee on Earth thanks to plate tectonics and ensuing climate change—then those mutations become critical to the organism’s survival. It’s a matter of what traits allow an organism to live long enough to successfully reproduce. That’s the central dogma of natural selection.

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CrazySheepherder1339 t1_j9am3mx wrote

Yes! Metal is ductile and malleable, so it can last a little longer than things that are more brittle, like a pen clip.

Suppose there are 5 bonds. when bend a metal clip, maybe 1 breaks, 2 reconnect to different pairs, and 2 stay the same.

In the example the "_" means a bond is broken

So if the connection is aa,bb,cc,dd,ee

it becomes a_,bc,cb,dd,ee. Notice how atom b and c switched their bonds. And the second time A_ , b_, c_, dc,ee

But with plastic it would be Aa,bb,cc,dd,ee then just break without switching A_,b_c_,dd,ee Then the second time, it breaks

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buzzwallard t1_j9alw6y wrote

In the case of human evolution, where the species is adapting the environment to its survival needs, the species evolution will halt entirely.

If our ability to adapt the environment in friendly ways is broken then we will see more adaptation.

There is a popular fantasy of 'evolution' that it is a directed force in itself, whereas evolution is not a driver it is an outcome of conditions.

Witness rapid evolution of the COVID virus as it mutates around our hostile vaccines and systems of immunity.

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ch1LL24 t1_j9alsk4 wrote

No, variable effects like that are not unique to Covid. The individual's specific biological situation, how they contracted the virus, and luck of the draw cause each infection to be somewhat idiosyncratic in most viruses. /u/redligand already has some good examples. I'll throw in Polio, which is known for its devastating paralytic effects but was also asymptomatic in 70% of children that contracted it. source

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rootofallworlds t1_j9alolh wrote

Acute radiation sickness. Specifically from neutron radiation. Even that is in a sense indirect - the neutrons knock nuclei about or get captured by the nuclear forces, but it's secondary emission of ionising radiation that does the real damage and that's electromagnetically.

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ArbutusPhD t1_j9akdec wrote

Essentially, the rate of mutation in individuals may remain constant, but without some environnemental pressure exerting a selective effect on individuals with advantageous mutations, there is no reason for those mutations to become reinforced each generation.

If 1/1,000 people randomly have slightly longer fingers, but there is no pressure in the environnement that grants long-fingered people an advantage reproducing, you won’t see an increase in long-fingered people over time; there will remain a roughly 1/1,000 chance that anyone you meet is long-fingered.

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picklesTommyPickles t1_j9ak8iq wrote

So basically when you bend metal, you're losing some information in the form of broken bonds? Bending enough times in the same location results in enough lost information to result in a fracture?

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