Wikipedia:Reference desk/Archives/Science/2017 July 12

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July 12[edit]

Intelligence difference between animals and humans[edit]

So... Why is it that I notice that many animals don't even really want to try to do what we do? For instance, why will a cat not see a human pick up a pencil to write, and see that same thing often, and then try to pick up the pencil themselves. (though I don't believe it'd work, I've never seen a cat try) What sort of lack of intelligence is this really? To make the decision "I will try to pick up a pencil like that human is" doesn't sound like it takes that much thought, especially if you can catch a mouse so easily. What field or term in neurology or psychology refers to this? Something that an animal could possibly think of, but that they won't?

To expand my question, in a similar manner, what is one of the things that a human would pretty much never decide to do that we probably could at least think of trying to do? I really can't think of any examples, because whenever I think of an example of one of these things I can almost definitely imagine some human doing that thing, no matter how crazy or stupid it sounds; like trying to jump to the moon with his or her own two feet. Yeah I think some human would be crazy enough to try that.

But this seems to be because humans are so diverse in thought, and really maybe a human could think of or perceive or try anything? Philmonte101 😊😄😞 (talk) 01:30, 12 July 2017 (UTC)[reply]

The term is observational learning. Spitballing, curiosity is also probably important here (sadly we have no article on animal curiosity that I can find). What if the cat totally understands what you're doing, but just doesn't want to copy you? Someguy1221 (talk) 03:05, 12 July 2017 (UTC)[reply]
It has puzzled me for some time how the dog, despite being in close proximity to humans for thousands of years, has never learned to raise one leg and point to something, such as its food bowl when it wants food. Instead, all it can do is bark and run back and forth from the object. Akld guy (talk) 07:44, 12 July 2017 (UTC)[reply]
Akld guy based on the excellent post by SteveBaker here, the answer may be that dogs equate humans' hands with extra mouths, rather than with paws. Adrian J. Hunter(talkcontribs) 08:26, 12 July 2017 (UTC)[reply]
It may also puzzle dogs how the human, despite being in close proximity to dogs for thousands of years, has never learned to walk on all fours, raise a leg and.... Proximity learning only works between animals of the same species; the dog or cat does not identify with the human or their wish to pick up a pencil. Similarly you don't train a dog to do tricks by doing them yourself.--Shantavira|feed me 08:02, 12 July 2017 (UTC)[reply]
As anyone who has interacted much with dogs knows, dogs 'point' by attracting a human's attention and then directing their gaze, which any dog-familiar human readily understands. This natural, mutually understood interaction has been refined by artificial selection in the particular dog breeds known as 'pointers', but the unaugmented version works well because over the thousands of years that dogs became self-domesticated by their associations with humans, humans also Coevolved to better interact with dogs, in what might be termed "co-domestication" (see Section 3.6 Convergent evolution between dogs and humans). {The poster formerly known as 87.81.230.195} 90.204.181.91 (talk) 08:38, 12 July 2017 (UTC)[reply]
Dogs can learn to point, it's just they normally they do so with their face and eyes rather than their paw (after all, dog anatomy is different to ours, and their "wrist" is effectively just a second knee - they lack the ability to point as precisely as we can.) Smurrayinchester 09:28, 12 July 2017 (UTC)[reply]
Pointing requires, apart from a faculty for cooperative behavior, a certain recursive way of thinking that (trigger warning) may well be unique to humans. Chimps are generally bad at understanding finger pointing (apparently, worse than dogs.) Some actually believe the neurocircuitry for pointing, creating joint attention, shared intentionality etc had to be already in place for speech to evolve. I once worked in a manual job with people whose language I didn't speak. You won't believe how well one can get along by just pointing at stuff, showing things etc, they instantly knew what the problem was and could help me Asmrulz (talk) 13:03, 12 July 2017 (UTC)[reply]
Our cat does like to grab pens, but not to write . Interestingly they have their own limited language, which we can learn and exploit to our advantage. I'm not a cat or a dog, but I'm pretty sure that they simply find pointless that we mysteriously gaze at paper and computers, except for the fact that those objects steal our attention from them... But it can be fun to watch their amazed reaction and wondering when we do peculiar things or manipulate new objects. They probably are trying to understand what occurs for a moment (the aforementioned curiosity is also a factor here) and to evaluate threat and safety, if it can be used as a toy or food, etc. Their needs are simple and they are not very interested in anything beyond those, we can trick them into doing things they would not normally do, but they don't do them for the same reasons we do (except perhaps for the rewarding factor)... Animal cognition is probably a good starting point to read more about the topic. —PaleoNeonate - 12:56, 12 July 2017 (UTC)[reply]
Oh, a point I was thinking about before posting, but forgot to include: humans are capable of abstract symbolic thinking. This is what allows us to develop complex language, to analyze, classify, develop theories and technology, etc. We are even capable of metacognition and we seek answers to transcendental questions... —PaleoNeonate - 13:28, 12 July 2017 (UTC)[reply]
You guys are hopefully outdated. About 300 years ago a man named Gulliver in one of his numerous travels came across a race of Houyhnhnms. If you don't know how to pronounce it, ask your horse if you happened to have one. They were horses, but highly intelligent. Needless to say they had language and a developed culture. They also dominated another race, Yahoo. Yahoos still survive in Silicon Valley but their future is questionable. Jonathan Swift is the man who wrote the account about this remarkable adventure. He-he. --AboutFace 22 (talk) 13:49, 12 July 2017 (UTC)[reply]
Reference deskers try to provide references. Houyhnhnms are a race of intelligent horses described in the last part of Jonathan Swift's satirical Gulliver's Travels in 1726. Blooteuth (talk) 15:35, 12 July 2017 (UTC)[reply]
Mirror neurons are important here. They are involved in the "learn by copying" process. For animals which lack those, they don't seem to "copy for copying's sake" (also known as "aping", because primates are particularly into this behavior). However, they do still do "goal based copying". For example, if a dog wants out, and has observed that the doorknob must be turned to get out, he may very well try turning it with his mouth (and, if large enough, he may succeed). StuRat (talk) 16:26, 12 July 2017 (UTC)[reply]
Re the last observation: it can depend greatly on the intelligence (in the broad sense) of the individual dog. Friends of mine owned two sibling English springer spaniels: one of them figured out (on his own) how to open a particular door they both frequently wanted to pass through (by pulling down with his forepaws on the lever-style door handle), and did so many times every day; his brother, despite observing this many times, never even attempted the same feat and had to wait until someone opened it for him. {The poster formerly known as 87.81.230.195} 94.9.9.203 (talk) 09:09, 13 July 2017 (UTC)[reply]
I once observed two cats in a room with the door closed. Many times they had seen someone turn the round doorknob and open the door. After an extended time in the room one cat climbed on a table by the door and started rotating the doorknob with its paws, while the other stood on the floor with its claws in the gap at the edge of the door and pulled on the door. No one had spent time teaching them to do this and in the end it was unsuccesful, except that after a while I opened the door and let them out (so maybe it was successful).Edison (talk) 04:01, 14 July 2017 (UTC)[reply]
We're fortunate we have opposable thumbs that we can leverage to outwit our pets... - Nunh-huh 04:06, 14 July 2017 (UTC)[reply]

How does polysiloxanes effect scar development?[edit]

How does polysiloxanes, common in the scar-treatment gel "Kelo Cote" effect scar development? Are these polysiloxanes become a permanent part of the scar tissue, or what? 109.66.156.177 (talk) 01:54, 12 July 2017 (UTC)[reply]

According to the best sources I can find, "the mechanism of action is unknown". That said, scar treatment gels were preceded by solid scar treatment sheets that most likely were not diffusing into the skin. There are a number of theories as to how scar treatments work that you can read about here, if that's not behind a paywall for you. Someguy1221 (talk) 03:02, 12 July 2017 (UTC)[reply]
My plastic surgeon says that it keeps the scar tissue hydrated. That is true of the silicon sheets, as the skin underneath gets distinctly clammy. Whether that really improves scarring is a whole nuther thing. Greglocock (talk) 06:53, 12 July 2017 (UTC)[reply]

Animal intelligences.[edit]

In the view of evolution, humans brains started to get smarter when we learned how to make fire and cook meat. They say that put a big speed on human brains intelligence. Then like at carnivores (like wolves and cats) are in general more intelligent than herbivores (like giraffes and hippos). I don't think anyone knows, but who do you guys think are the dumbest carnivores, vs. the smartest herbivores? Heh. (In this case, omnivores are still compared as carnivores).

2ndly, all carnivoresly expected evolved from a former herbivore. Are there are species that are herbivores that evolved from a carnivore? Thanks. 50.198.21.45 (talk) 14:00, 12 July 2017 (UTC).[reply]

Who says carnivores are more intelligent? And who says they evolved from herbivores? ←Baseball Bugs What's up, Doc? carrots→ 14:10, 12 July 2017 (UTC)[reply]
The first carnivore must have evolved from a herbivore, perhaps with a scavenger being the first step. As for being more intelligent, the theory is that this is needed to catch prey. (While intelligence also helps at avoiding predation, some prey animals just overwhelm their predators with numbers, such as locusts, or spend much of their time some place safe, like penguins.) Of course, not all predators are intelligent, as in the case of predatory plants. StuRat (talk) 16:43, 12 July 2017 (UTC)[reply]
the theory is that... - which theory? Link? TigraanClick here to contact me 16:54, 12 July 2017 (UTC)[reply]
Don't think it has a specific name, but here's a source at the University of California listing many factors that control animal intelligence, and this is number 1: [1] (it's about 2/3 down the page, do a CTRL F on "carn" to find it quickly.) StuRat (talk) 18:22, 12 July 2017 (UTC)[reply]
  • Apart from humans, the most intelligent* animals are generally thought to be other great apes, and these include gorillas which are herbivores (see Gorilla#Diet) and very intelligent (see Gorilla#Intelligence). (* Really, it's hard to say whether one animal is more intelligent than another, because there are so many ways to be intelligent. Who can tell if a dolphin is cleverer than a chimp, for instance?) Smurrayinchester 15:08, 12 July 2017 (UTC)[reply]
Typically fish have smaller brains (relative to body mass) than reptiles, which are again smaller than mammals. While imperfect, brain size often correlates with proxy measures of intelligence. So off-hand, I would look for carnivorous fish for relatively low carnivore intelligence and herbivorous mammals for relatively high herbivore intelligence. However, you'd have to find specific studies to get anything concrete and measuring intelligence across species is fraught with difficulties. Not sure about pure carnivores giving rise to herbivores, though there probably are some, but bears are typically omnivorous, while the Giant Panda has evolved to be a very specialized herbivore. Actually, the Panda is interesting in part because it isn't very well-adapted to its diet and doesn't obtain nearly as much nutrition per kilogram of food as most herbivores. Dragons flight (talk) 17:01, 12 July 2017 (UTC)[reply]


Yep, giant pandas had carnivorous (or at least omnivorous) ancestors, and there's the famous (almost totally) vegetarian spider Bagheera kiplingi, who's snuck in to an ant-plant mutualism, and steals beltian bodies, which are basically nature's veggie burger. All the herbivorous bees are derived from carnivorous wasps. See here [2] for some nice discussion of evolution of intelligence. It's not so simple as carnivores are generally smarter. Omnivory and social structure also have a lot to do with animal cognition. SemanticMantis (talk) 17:20, 12 July 2017 (UTC)[reply]
Here's a good accessible peer-reviewed article that summarizes a lot of our current understanding on how intelligence evolves, with lots of good references for further reading [3]. SemanticMantis (talk) 20:03, 12 July 2017 (UTC)[reply]
A highly developped brain requires a lot of energy and long supervised development time. However when environment pressures require a certain level of intelligence and fast-paced adaptation to survive, species that cannot rapidly cope with changes can become extinct by selection. When larger territories are needed, more complex food-processing or hunting needed to eat, more skill and organization required to achieve mating and raise offspring, larger group cohesion needed to cope (including for task assignment and specialization), culture transmission needed to keep and improve acquired skills, etc... It becomes more plausible for this extra energy to be offset by the advantages more complex brains provide. Evolution of human intelligence summarizes some of those aforementioned aspects. —PaleoNeonate - 21:41, 12 July 2017 (UTC)[reply]
Such explorations as above should start with brain anatomy. Human brains are much more complicated than a cat's brain for instance and seeing what my cat actually can do always marvels me, she is so intelligent and in many instances she even mewing appropriately. She is able to jump on the door handle and open the door. Cats are unbelievable. It's been said that domestic cats and dogs can learn and understand 250 words. I think my cat is already over that limit. :-) Human brains aside form massive cerebral cortex, many gyri (folds) existing to increase the cortex surface even further, have two unique areas that are absent in all other species. They are Wernicke's area (receptive understanding of language) and Broca's that controls motor language function. Sure there is no direct correlation between the brain size and intelligence, Frederick Gauss, the Prince of Mathematics, reportedly had a very small brain, but still his brain was probably larger than that of many animals. Exceptions are dolphins and elephants, but those quite intelligent in their own right. They still lack those specialized areas. --AboutFace 22 (talk) 00:49, 13 July 2017 (UTC)[reply]
Yep, and other animals presumably have specialized brain areas we lack, like for echolocation, or greatly expanded areas, like for processing scents. However, we don't normally consider this type of brainpower "intelligence". StuRat (talk) 00:57, 13 July 2017 (UTC)[reply]
It's hard to tell how big a brain is needed for intelligence. Portia (spider) with 60,000 neurons for instance is considered quite intelligent. It is also indubitably a carnivore. Dmcq (talk) 09:40, 13 July 2017 (UTC)[reply]

connect opamp outputs together?[edit]

as a poor man's mixer, instead of a proper summer circuit (the outputs go to either sides of a pot and the taper contact is the output of the circuit) - is this kosher? 80.171.94.156 (talk) 17:27, 12 July 2017 (UTC)[reply]

You'll need to connect them through a couple of resistors. This is the standard circuit for summing two signals. Take a look here [4]
Mostly you need to just follow the rule of following a low impedance output with a high impedance input (and that "input" can be as simple as a couple of resistors). This avoids the following stage loading the preceding stage, and especially for avoiding that loading changing if you move a pot. Andy Dingley (talk) 21:14, 12 July 2017 (UTC)[reply]
The circuit "[Opamp] outputs go to either sides of a pot and the taper contact is the output" can be used as a simple crossfader (it does not sum the signals). The potentiometer should be a linear-taper type with resistance R ohms noting that each op-amp must be capable of driving a load of R/2 ohms and the following stage should be a buffer with high input impedance. Blooteuth (talk) 16:10, 13 July 2017 (UTC)[reply]