Recent comments in /f/todayilearned

Thin-Rip-3686 t1_jdr6ejt wrote

Reply to comment by Tyrrox in TIL that the ratio of male births to female births is 51/49%, and it's thought the ratio of X and Y chromosomes in the man's sperm is most likely the cause. by iKickdaBass

You forget the importance of percentage of overall mass. It’s probably more like the race performance difference of two identical cars, one with 3% more fuel in the tank, versus one with 3% more overall weight.

Little effects like this can produce outsized results or no change in results, but the “sized” result is way less than 2%.

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Hamiltoned t1_jdr6758 wrote

Reply to comment by IkmoIkmo in TIL that the ratio of male births to female births is 51/49%, and it's thought the ratio of X and Y chromosomes in the man's sperm is most likely the cause. by iKickdaBass

Or those 200+ million men fuck each other instead of women because non-hetero sexuality is a trait that survived in our evolution because it allows for an even higher % of the population to function as a non-competing component of the tribe.

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so_bold_of_you t1_jdr5vdr wrote

Reply to comment by I2eB6L in TIL, the placenta that forms with a fetus isn't created by the mother. It grows from the fertilized egg and some fetuses actually develop outside the uterus attached to the intestines in the body cavity. by darw1nf1sh

Difference between passive and active. An environment is passive in the sense that the resources are there, but unless an active agent makes use of them, resources stay in their raw forms.

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FillsYourNiche OP t1_jdr561s wrote

Reply to TIL African wild dogs use sneezes to cast their vote on whether they are ready to begin a hunt. Researchers noted a minimum number of sneezes required to rally the group, with sneezes from dominant individuals worth more than other dogs. by FillsYourNiche

Science also has an article Wild dogs vote to initiate a hunt by sneezing.

Journal article source Sneeze to leave: African wild dogs (Lycaon pictus) use variable quorum thresholds facilitated by sneezes in collective decisions.

Abstract:

>In despotically driven animal societies, one or a few individuals tend to have a disproportionate influence on group decision-making and actions. However, global communication allows each group member to assess the relative strength of preferences for different options among their group-mates. Here, we investigate collective decisions by free-ranging African wild dog packs in Botswana. African wild dogs exhibit dominant-directed group living and take part in stereotyped social rallies: high energy greeting ceremonies that occur before collective movements. Not all rallies result in collective movements, for reasons that are not well understood. We show that the probability of rally success (i.e. group departure) is predicted by a minimum number of audible rapid nasal exhalations (sneezes), within the rally. Moreover, the number of sneezes needed for the group to depart (i.e. the quorum) was reduced whenever dominant individuals initiated rallies, suggesting that dominant participation increases the likelihood of a rally's success, but is not a prerequisite. As such, the ‘will of the group’ may override dominant preferences when the consensus of subordinates is sufficiently great. Our findings illustrate how specific behavioural mechanisms (here, sneezing) allow for negotiation (in effect, voting) that shapes decision-making in a wild, socially complex animal society.

The journal article is open access, so anyone can read the entire thing if they are interested.

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fourdac t1_jdr4j4q wrote

Reply to comment by Admetus in TIL Early Superman comics taught kids how to achieve super-strength through exercises in lifting armchairs, getting a super-grip, and achieving super-vision by glancing at distant and near objects repeatedly by Ok_Copy5217

No man, that’s parents who don’t get their kids off the screen. City fuckers don’t live there to survive one block to the next, they take time off to sightsee and there’s a lot more to see in the city.

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shdwrnr t1_jdr3wdz wrote

Reply to TIL Early Superman comics taught kids how to achieve super-strength through exercises in lifting armchairs, getting a super-grip, and achieving super-vision by glancing at distant and near objects repeatedly by Ok_Copy5217

Well, when you need to be able to draft your citizens into military service, there's a bigger push to teach kids how to be healthy and fit. When you instead have an all volunteer force and big lobbyist shoving money at the government to get people to buy more cereals and dairy you wind up with the food pyramid posters in every classroom.

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VoxEcho t1_jdr2tj6 wrote

Reply to comment by Dubanx in TIL: Thanks to poor internal communication at NASA, information about a spacesuit water leak wasn't properly communicated. Later, Astronaut Luca Parmitano almost drowned on a July, 2013 ISS space walk, his helmet filling with several liters of water before they could get him back inside. by OvidPerl

Boil is doing a lot of heavy lifting there. It wouldn't disappear -- it has no where to go. It would just get very cold, which is essentially what you would expect of anything exposed to the vacuum of space. It wouldn't turn to ice, though, it would turn to vapor -- thus the "boiling". It would still, for any functional purpose, be a large amount of water lingering around the immediate vicinity of his head.

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-1KingKRool- t1_jdr05ow wrote

Reply to comment by nrkbarnetv in TIL Early Superman comics taught kids how to achieve super-strength through exercises in lifting armchairs, getting a super-grip, and achieving super-vision by glancing at distant and near objects repeatedly by Ok_Copy5217

The ‘increasing need for eye correction’ is due to better detection of poor vision.

Harvard states that eye exercises do not improve vision, and at absolute best only slightly delay the usage of corrective lenses, although they posit it’s more likely that, once lenses are worn, people acclimate to the improved vision, and no longer find their previous levels of vision acceptable.

https://www.health.harvard.edu/diseases-and-conditions/the-lowdown-on-eye-exercises

Saying it’s due to recent developments is like saying people are only developing celiac disease in the last few decades. People have had it for millennia, they just suffered without us knowing what caused it before.

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