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Wikipedia:Reference desk/Archives/Science/2021 June 11

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June 11

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Aquatic Locomotion of Apes

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Looking at Aquatic Locomotion (after watching Disney's Tarzan), are there any apes which are even close to Humans in their ability to swim? (Let's say > 100 meters) Naraht (talk) 00:46, 11 June 2021 (UTC)[reply]

This study details two apes who learned to swim in captivity. The max distance reported was about 12 meters (less than half a swimming pool), so not very good compared to even the average person. Even so, these apes are very unique in their ability to swim, as wild apes avoid deep bodies of water, and few reports of them swimming have been made. Zoos typically use water moats as an effective way to keep apes in their habitats, for example to prevent them climbing up the walls. The article concludes that the lack of swimming ability in apes is due to behavioral differences as a result of the terrestial life of apes and not any innate physical barriers. It also notes humans do not swim instinctively either, meaning swimming is not a natural ability of ours but rather an ability we invented. Pinguinn 🐧 01:31, 11 June 2021 (UTC)[reply]
I call the last assertion into doubt. I have read on several occasions that young babies spontaneously exhibit natural swimming ability when introduced (under close supervision, of course) into sufficiently deep water, and I myself personally witnessed a young baby of barely walking age accidentally fall into a model boating lake (in Gorleston-on-sea) and swim using doggy paddle quite effectively and with apparent enjoyment (audibly laughing) for several seconds until an adult rescued it.
I would not dispute that this ability is seemingly lost once children become older, and has to be re-learned later, but I hypothesize that this may be due to cultural practices which do not permit early instinctive swimming to be continuously practiced.
My dim childhood memories of the Tanka (or boat) people of Hong Kong (where I lived on the Stanley Peninsula for two years), is that their children of all ages down to babyhood routinely swam, but given the span of time (approaching 60 years) and my lack of observational rigour at age 6–7, I may be mistaken in this. {The poster formerly known as 87.81.230.195} 2.122.0.58 (talk) 04:46, 11 June 2021 (UTC)[reply]
"Re-learned" is not the appropriate term, since the "swimming" of newborn infants is part of a set of neonatal reflexes on submersion and not learned behaviour. These reflexes disappear spontaneously and are typically gone when they are about one year old, when the infant becomes a toddler and starts loosing the baby fat that helps to keep them afloat. Early supervised "swimming" may make the child feel comfortable in deeper water, but swimming lessons before that time will not be very effective in terms of later swimming ability.  --Lambiam 07:13, 11 June 2021 (UTC)[reply]
We have an Infant swimming article, that includes mention and links to the relevant reflexes. DMacks (talk) 14:11, 11 June 2021 (UTC)[reply]
Here is a video of a mandrill swimming for about 40 seconds (or at least managing not to drown) between jumping into the middle of a moat and succeeding in getting out.  --Lambiam 07:23, 11 June 2021 (UTC)[reply]
Not apes, but primates at least, Japanese macaques are known to swim in hot springs - see JAPANESE MACAQUE SWIMMING. Alansplodge (talk) 12:54, 11 June 2021 (UTC)[reply]
"This video may be inappropriate for some users. Age-restricted video (based on Community Guidelines)". Of all the inappropriate crap on Youtube, this is what they flag? DMacks (talk) 14:09, 11 June 2021 (UTC)[reply]

Extracting energy from hydrocarbons without producing CO or CO2

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Does any chain of reactions exist which is exothermic, takes hydrocarbons and abundant gases (such as oxygen or nitrogen) as reagents, and does not produce carbon monoxide or carbon dioxide as an end product? NeonMerlin 04:25, 11 June 2021 (UTC)[reply]

This is the first result I found using your header in Google. --Jayron32 14:03, 11 June 2021 (UTC)[reply]
Jayron32's link includes a Youtube video >1h, but the slides are available separately here. Be warned that it is a fairly chemistry-heavy presentation. TigraanClick here to contact me 14:59, 11 June 2021 (UTC)[reply]

In regards to Rep Gomert's question.

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In regard to: https://thehill.com/homenews/house/557558-gohmert-asks-if-federal-agencies-can-change-earth-or-moons-orbits-to-fight

Would a unified Humanity (Beijing, Moscow & DC's biggest dispute is in the sport of Curling) within 15 years be able to noticibly (either 1% decrease or 1% increase) alter the expected change in the Moon's Orbit year over year? (Significantly changing the appearance of the surface of the moon from the explosion is just fine)

The closest that I've seen to calculating this actually a larger question in regards to Space:1999 indicating that all of the energy produced by humans wouldn't be enough to accelerate the moon even out to Mars Orbit, must less interstellar...Naraht (talk) 16:07, 11 June 2021 (UTC)[reply]

It is more likely that this was an example of a politician who used a leading question, in a form of grandstanding, in an effort to disclaim any agency or responsibility for addressing the real problem: in other words, you're trying to parse an argument based on logical fallacy in a quest for some kernel of scientific accuracy.
If you're actually interested in the science, here is a nice open-access review article from American Geophysical Union: Reflecting on 50 years of geoengineering research (2016). "...Leading experts in the field of geoengineering research ... contribute brief reflections on the development of the discussion over the past decade and to consider where it may be going in the next 10 years..."
The point is, real scientists have scientifically considered whether humans have the capacity to use our technology to intentionally substantially alter Earth's climate. Changing the orbit of Earth, its moon, or any other astronomical body, is not the most prominent plausible path in the near-term.
When a politician asks a question to which the answer is an already-known negative, the politician is probably not seeking new information - they are probably trying to perpetrate one or more logical fallacies - in this case, I would say an association fallacy - by planting the seed-idea in the listener's mind: if we can't change the orbit, why should we do anything?
Phrased another way: politicians are not stupid - and they're not even necessarily scientifically illiterate - they just act that way when it serves their interest. Arguments - especially in the United States Congress - are frequently won through intentional application of logical fallacy, inaccurate fact, and emotional manipulation: when facts are not on your side, why bother using them?
Nimur (talk) 16:27, 11 June 2021 (UTC)[reply]
Louie Gohmert is more full of shit than a manure truck. I would pay him less than no mind on any utterance from his mouth. He is on record saying that masks cause COVID-19 and is also on record as saying that the Alaska pipeline would lead to increased fecundity of caribou. His nonstop and incessant bullshit isn't even worth fact checking. You can ignore anything he says, and doing so will likely make you all the smarter for it. --Jayron32 16:33, 11 June 2021 (UTC)[reply]
Some politicians say crazy stuff just to get the media riled. Like when Trump talked about ingesting Lysol to treat COVID. ←Baseball Bugs What's up, Doc? carrots→ 18:14, 11 June 2021 (UTC)[reply]
He was musing aloud whether injecting disinfectants, presumably in patients' veins, might treat COVID-19, after considering internal UV irradiation (by mini UV lamps circulating in the bloodstream?). I believe this was meant to be a serious suggestion, which he hoped experts would consider.  --Lambiam 21:21, 11 June 2021 (UTC) ([Watch on YouTube].)[reply]
Trump has a sadistic "sense of humor", so it's hard to know for sure what he was on about. ←Baseball Bugs What's up, Doc? carrots→ 21:50, 11 June 2021 (UTC)[reply]
Trump likes reading Facebook and has the kind of conspiracy theorist mentality that's open to any ideas that are strongly opposed by 'mainstream media' (ie, the entire scientific community and anyone with a modicum of education), and I suspect that he was genuinely musing about the possibility of using so-called "Miracle Mineral Supplement" to treat COVID, which was being touted on Facebook at around that time.

The Guardian reported that while the source for Donald Trump having suggested coronavirus could be treated with disinfectants remained unknown, Mark Grenon had written a letter to Trump only days earlier recommending MMS as a treatment, as well as posting on social media and sending a bottle of MMS to the White House.[1]

nagualdesign 22:58, 11 June 2021 (UTC)[reply]

References

  1. ^ Pilkington, Ed (24 April 2020). "Revealed: leader of group peddling bleach as coronavirus 'cure' wrote to Trump this week". The Guardian. Retrieved 2 February 2021.
(ec)No, mankind (at the current technological level) is not be able to change the orbit of the moon by one percent either way, much less within 15 years. The moon weights 7.342E22 kg. The gravitational force between Earth and moon is about 2E20 N. For a 1% distance, we can assume gravitational attraction to be nearly constant, so you would need to move the moon 3844000 m (1% of the average distance) against a force of 2E20 N, so an energy of 7.688E26 Joule. Or of 24378488077 Gigawatt-Years. Unless I dropped a zero somewhere, that is 1.2 Million years worth of the current total primary energy production of humanity. --Stephan Schulz (talk) 16:43, 11 June 2021 (UTC)[reply]
I rather doubt Stephan Schulz's reasoning here, even though the result is probably in the correct ballpark. I think they make the assumption that moving the moon requires to apply a force equal (or similar to) the gravitational pull of Earth on the Moon (and then calculate the work for a given distance). That assumption is not correct: if we fired a laser pointer at the Moon, the radiation pressure would be very low and the change of orbit over a year negligible, but it would slightly affect the trajectory, and with enough patience the desired deviation could be achieved.
However, because gravitational forces are conservative, we can make a reasoning of potential energy. Displacing the Moon requires to change its (gravitational potential + kinetic) energy/ies. Now, the derivative of gravitational potential energy with distance is equal to the gravitational force, but the change in kinetic energy is not zero. Younger me knew how to do the calculations, but older me will just say that Kepler's third law will probably tell us that the change in kinetic energy is of the same order of magnitude as the change in potential energy at least when moving on different circular orbits. Hence taking the change in potential energy alone gives more or less the good result (again, that reasoning only works because gravitation is conservative). TigraanClick here to contact me 17:18, 11 June 2021 (UTC)[reply]
You think wrongly. I do not assume that any particular force has to the applied, just the old Energy=Force times Distance. But yes, I did not take kinetic energy into account. --Stephan Schulz (talk) 17:27, 11 June 2021 (UTC)[reply]
According to the virial theorem, the kinetic energy is exactly -1/2 times the potential energy. PiusImpavidus (talk) 09:33, 12 June 2021 (UTC)[reply]
Thanks! There was something nagging about 1/2 in my hindbrain. So 600000 years worth of current world energy production. That's about twice the time span of Homo Sapiens on Earth. If, given the question, we keep using that name ;-). --Stephan Schulz (talk) 11:27, 12 June 2021 (UTC)[reply]

Scott Manley's just posted a video about this: How to Move The Planet Earth To Save It From The Sun nagualdesign 18:32, 11 June 2021 (UTC)[reply]

If I carefully read the question (I didn't read the link though), it's not about a 1% change in the Moon's orbit, but a 1% change in the expected change of the Moon's orbit. The Moon's orbit changes at about 38mm per year (in semimajor axis), which makes the question: Can we change the speed of the tidal evolution of Moon's orbit by ±0.38mm per year within 15 years? That might be closer to feasible. Suppose we build dams connecting France to England and Scotland to Norway. This has been seriously proposed to protect the North Sea and Baltic coasts from sea level rise. That would eliminate tides from the North Sea, affecting the transfer of angular momentum by tidal forces between Earth and Moon. I doubt it would be a 1% change, but it won't be off by many orders of magnitude and may be measurable. Now, we can't build those dams in 15 years, but we can build them before the end of this century. PiusImpavidus (talk) 09:33, 12 June 2021 (UTC)[reply]
We can reuse Stephan Schulz's calculation which he made for another distance of 3.8e6m. We want here the result for 3.8e-4m, so it is easy to compute by multiplying the result by 1e-10. They found that the energy for their one-time pull was 1.2Mhyp (where hy=human year of production), so a one-time pull of 0.38mm requires 0.12 mhyp, or 0.01% of yearly primary energy production. While there would surely be massive engineering challenges in how to transfer that energy to push the Moon away or pull it in, and probably large conversion losses, it does look like it could be achieved. TigraanClick here for my talk page ("private" contact) 10:36, 14 June 2021 (UTC)[reply]
Pumping massive amounts of CO2 in our atmosphere causing a large sea-level rise is pretty much the only thing we can do that can have a measurable impact on the lunar orbit, see here. Count Iblis (talk) 12:19, 12 June 2021 (UTC)[reply]
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