18

As long as you have steady winds, you should be able to fly a kite. And if you can fly a kite, then you can fly: Man-carrying kites are believed to have been used extensively in ancient China, for both civil and military purposes and sometimes enforced as a punishment. The (636) Book of Sui records that the tyrant Gao Yang, Emperor Wenxuan of ...


15

The world has been there, done that, and has the T-shirt. The term 'telegraph' actually preceded the electrical version of the communication system. It was applied to light towers spread from city to city for long-distance messaging. The light towers were made obsolete by the electrical version. The word telegraph is derived from the Greek words tele, ...


13

Bloodletting and transfusion Hopefully, it won't even get to that. It's what the liver is for, after all. In general, any foreign contaminant to your blood is removed by either the kidneys or the liver, though mostly it's the liver. Any kind of poison inserted into someone's blood will eventually be processed by the liver. If the subject isn't in immediate ...


12

Yes this is entirely possible. In fact such systems have been used quite widely in times gone by. For example during the Crimean war the Russians used a series of semaphore signalling stations which allowed information to flow from the front to Moscow and on to St Petersberg in just a few hours. Where as British and French communications took days at the ...


11

The Copernican principle As L.Dutch pointed out, this would violate the Copernican principle, which essentially states that there's nothing special about observing the universe from any one place. Granted, this is not easy to test, as we humans only sit in one tiny portion of the cosmos. However, it's possible that the Copernican principle is incorrect, and ...


10

What you want is a form of heliograph, which is a fairly well-studied and used form of communication. These systems use a mirror to reflect sunlight at the target in flashes, so their maximum range is determined by the size of the mirror. Using large, emplaced mirrors and telescopes between fixed positions, ranges of up to 300km are possible, and your nation ...


10

Other posters have noted that a steady breeze can launch a kite, and that bungee cords were used to launch gliders. Modern gliders can also be launched using a powered winch to pull the tow cable and pull the glider down the runway. winch launch In order for the nomadic tribe to have more flexibility, they should also have developed a similar system, using ...


9

The closest to what you want are gizzards stones. Necessarily so, because the rotating part cannot be a biological organ in nature - not being connected to the body, it can't receive nutrients or be protected by the immune system. If you think it serves your purpose, move the stones upper in the digestive tract. Careful with the respiration, though.


9

2,4 dinitrophenol and chemical endothermy https://en.wikipedia.org/wiki/2,4-Dinitrophenol In living cells, DNP acts as a proton ionophore, an agent that can shuttle protons (hydrogen cations) across biological membranes. It dissipates the proton gradient across mitochondria membranes, collapsing the proton motive force that the cell uses to ...


8

The basic assumption behind our constant effort in producing physics theories is that they are valid in every place of the universe. This assumption has never been disproved so far, and if it was as you say, we would observe some hint of this jamming. For example we would observe a discrepancy between the distance of galaxies estimated via the Cepheid ...


8

No but you could invent one There has been research into this field but nothing definitive. Mader's Reptile and Amphibian Medicine and Surgery notes that "There are no safety or efficacy studies on the use of any psychoactive drugs for behavioral medicine treatment in reptiles." Later, Mader's offers a more detailed explanation. The role of monoamine ...


6

It's possible, albeit supremely unlikely It's not possible with conventional biology. That said, it's possible, albeit unlikely, with a bit of unconventional biology. The main problem you face is the 'teeth ring' - the rotating outer gear you illustrate in your diagram. It's simple not possible for that to be an organic component. However, fortunately for ...


6

Is it possible? Yes, build enough suspension bridges like you say and it will be covered Is it feasible? No, a post-post-apocalyptic society is not building technological marvels for minor protection, especially if a wall with guards will provide the same benefit. So it is more likely that this covering would be built pre-apocalypse. However, currently the ...


6

A tethered hot air balloon would work, particularly if they have ready access to a fuel source for said hot air. The grass itself may work, but that makes grass fires that much more dangerous. Another option would be A Big Kite, again tethered to a wagon. Needs wind instead of fuel. Considerably more dangerous if the wind cuts out. If you want to be a ...


6

Most female reptiles lack secondary sexual dimorphic features in general. It is often very difficult to sex reptiles in captivity without physically checking their cloaca, and a lot of times individuals will be just assumed to be male or female based on overall size or other features. In the vast majority of reptiles there are no obvious differences between ...


6

Refraction Refraction is based on light moving at different speeds through different materials. As soon as light travels everywhere instantaneously, all of optics goes out the window. Lenses, prisms, filters, lasers - it all doesn't work or is radically different. Which means that the aliens outside our system are operating under a completely different ...


5

And God saw the light, that it was good: and God divided the light from the darkness Our keepers have produced a habitat for us where physics works in a way that keeps things running and keeps us alive. Things we perceive as coming from outside our bubble must be simulations of some sort, like the distant ocean background pasted up against the back wall of ...


5

Not plausible at all, unless everything we see out there is faked. The aliens would have built a "bubble" all around the Solar System (or a good part thereof - there is something like that in Giant's Star by James P. Hogan, and in The Crystal Spheres as well), and the inner wall of the bubble is a sophisticated "screen". Appropriate emitters simulate a ...


4

[D]oes my magic system seem at least somewhat grounded in reality? Not exactly. Reality doesn't have infinitesimal vibrating strings of which certain people have the mutation which allows them to manipulate them in order to screw with people's minds, heal faster than they should be biologically capable of, or whip around water as if control by telekinesis. ...


4

A sideways take would be to say the evolution is directed and not natural. In the book "The Age of Em", the author postulates that human consciousness can be emulated on a silicon substrate-a computer brain. Since the electronic impulses in a computer travel faster than the electrochemical impulses in the brain by a factor of 1,000,000 , the emulated human ...


4

You are thinking of ionic wind. https://www.theguardian.com/science/2018/nov/21/first-ever-plane-with-no-moving-parts-takes-flight Your critter generates positive ions at the head and recaptures them at the tail. Air entrained by movement of the ions pushes up on wings to give lift. This is a doable deal for a machine. How exactly a creature is going ...


4

Magnetic levitation is a topic of interest in physics. Within this noble and holy subject, there is a subtopic called Diamagnetic Levitation: A substance that is diamagnetic repels a magnetic field. All materials have diamagnetic properties, but the effect is very weak, and is usually overcome by the object's paramagnetic or ferromagnetic properties, ...


4

A single arch from rim to rim with no supports? No way. Dallas Cowboys Stadium has the longest single-span roof in the world at 373m. You're talking about arches 29,000m long, or over 77 times as far. And not just two of them (like the stadium) but thousands along the entire length of the canyon. That is not remotely within the realm of what we will be able ...


4

It isn't possible with our current biology for the same reason we can't have organic chainsaws: we need loose parts. Everything in an organic being is interconnected by muscles and other systems like blood vessels. For you to have a jaw that spins in a single direction indefinitely, you'd need a loose set of bones and something to rotate them. Sadly you won'...


4

There's three main ways we remove things from blood. 1) Supportive care so the body's natural systems can handle it. So, proper hydration and electrolyte balance, cardiopulmonary support if necessary to make sure the kidneys and liver get enough oxygen, and in some cases there are medicines that target specific contaminants. 2) Dialysis. The same thing ...


3

This species could evolve from a predatory creature that feeds on much larger creatures. It would kill its prey using a long conical fang, and cut up its prey using a saw-like structure, and . Its prey might evolve to have sticky blood which traps the predator's fang. To avoid this, the predator may evolve to drop its fang to escape, and regrow it. They ...


3

Not gonna lie here, that looks way more like an disadvantage than an advantage. The main problem here is that this seems like an unnecessary redundancy. Yes, morays have 2 sets of Jaws, but the secondary set is inside the mouth and helps pull prey inside. In this case, rather than help, the second jaw gets in the way. Problem 1: To open the lower set, you ...


3

As to 1, yes. Sharks survived the K-T extinction, though not every species did and there was a general turnover from Lamniformes to Carcharhiniformes and a huge dieoff of freshwater sharks and rays, and they survived the P-T and T-J extinctions before that. You're going to have to hit the ecosystem a lot harder than just an extended PETM to wipe them out. ...


3

You could do this quite easily if you had access to fairly strong fabric & ropes (silk might work) and the necessary knowledge. See for instance parasailing: https://en.wikipedia.org/wiki/Parasailing Instead of a boat, you use a team of horses. With proper design and good thermals, once you're aloft you could probably drop the tow line and ascend ...


3

If we're going hard science, we would have to imagine some kind of biology which evolved from the beginning to use lightning energy. It's hard to imagine an animal acquiring that talent from a different evolutionary line without getting fried. So let's imagine how a single-celled organism might use lightning. On a planet with the right chemistry, and a ...


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