Recent comments in /f/askscience

makary12 t1_j6aaa4q wrote

Reply to comment by LaRoara42 in Shouldn't goldilocks zones shift over time? by LaRoara42

That would be a nope from chief. My understanding is that the earth has always been in the Goldilocks zone. I think you're severely underestimating the time it would take for the Goldilocks zone to move far enough so that earth is no longer within it. We would definitely know if we changed planets; that is not something that would fly under the radar.

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Grymflyk t1_j6a9fim wrote

Reply to can gemstones be melted into a gradient? by Acceptable_Shift_247

Best bet is to simply talk to a jeweler/jewelry maker, tell them what you want and allow them to create a ring that communicates the message without the use of alchemy or planet scale forces. If you have the money, you will be amazed at what can be created for you by a talented maker.

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LaRoara42 OP t1_j6a8s4q wrote

Reply to comment by VoilaVoilaWashington in Shouldn't goldilocks zones shift over time? by LaRoara42

So...could that mean...we evolved as scientists think we did but maybe we did that on another planet in our our system and had to move to Earth when the goldilocks zone shifted?

....maybe? Even in a "plausible sci fi" way?

Or is the change over too many billions of years to make any sense?

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agate_ t1_j6a7c2x wrote

Reply to comment by kilotesla in Why is wind energy generation greater during the night? by ZeroTheHero524

Neat, I hadn’t seen the data presented that way before. Your graph also shows an important difference between land and sea: because the sea surface is usually smoother than the land (no trees and hills), there’s less turbulent mixing and the boundary layer is usually thinner. So the neutral point you’re talking about is much lower at sea.

The weaker, thinner boundary layer also means the overall wind speed is much higher at sea, which is why people go to the trouble of building offshore wind turbines.

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DanYHKim t1_j6a4zvk wrote

Reply to comment by Sir-HP23 in Has a new animal species evolved since mankind’s existence? by coding_ac

I've always wondered about moths being captured by streetlights. I figure that those moths are less likely to reproduce, since they are bashing their heads against a hot lamp, and are also picked off by bats all night long.

So, if there were a genetic component to their dependence on light for night flying orientation, could a mutation emerge that might reduce that dependence? That might allow a subset of moths to escape the artificial light. Such a mutation would reduce flight efficiency at night, since the moth may also not be well-oriented by the moon, and so would tumble in flight.

It might be useful to collect "country" moths and "city" moths, and test them for the ability to escape from strong artificial lights. One could then try cross-breeding them to find out if the variation is an inherited trait. If so, the genetic source of the variation might be found.

I think I once posted this question here on Reddit somewhere, and and alert reader gave me a link to a paper on the subject. It turns out that there are variations in light orientation dependence between moths that live in the city and those that live out in the darker countryside. I do not recall where I left the article, but I will try to find it .

In any case, there are selective pressures that are kind of associated with the presence of modern humans and our impact on the environment which have an impact on the behavior or morphology of different living things, and which may lead to a level of diversity that could be considered the emergence of a new species.

I believe there's also some work being done on the genetics of rats that live in the city, and how genetic variance may have behavioral adaptations which are more advantageous in an urban environment.

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