So what about puppies and kittens at the nipple? Is it then a pressure/oral “palpitation” exertion? (I don’t believe this is addressed.)
Is there some sort of “complete cheek/incomplete cheek” evolutionary or species distinction? Animals have an astounding range of ingestion modes; there must natural surveys (temporally linear or not) of that–any suggestions?
I ask this following up a similar interest of mine in breathing/smelling and “incompleteness”: I cannot re-find the cite for–what I believe I am recalling correctly–the (“Linnean?”) distinction made between animals with “split nostrils” and those without, and would love any help on that too.
Nursing isn’t really sucking like when you drink from a straw. It’s more like using your tongue to do sort of a milking-a-cow action which starts the milk flowing. It’s instinctive.
Suction is such a tiny force …its less than capillary action …
Now, if the question was " Do cats and dogs drink by allowing the atmosphere to push liquid in, by inducing lower air pressure in the throat ? "… thats a better question…
I say that, because I am sure carpet dust extraction machines do the same thing… The clean by pushing air out their exhaust… then there is lower pressure on the intake side, and the atmosphere pushes air in … U turning in through the carpet into the nozzle…
As for suckling, it may well be that at the age they need to suckle, they have a different structure in the throat… that allows them to breath through the nostrils to the trachea … and accept atmospheric pressure, or lips , driven fluids through the mouth into the oesophagus…
As for suckling, it may well be that at the age they need to suckle, they have a different structure in the throat… that allows them to breath through the nostrils to the trachea … and accept atmospheric pressure, or tongue driven fluids through the mouth into the oesophagus… Human infants do, at least in new born, so I guess cats and dogs would too ?
Of course the dog and cat and human can squash water to the back of the throat with its tongue, thus avoiding the air pressure toward the lungs problem… (the air flow would only happen if the mouth was open, and that causes dribbles and noises…)
The older human can use air pressure, with a sense of timing ,with the head held so the oesophagus is upward of the lips, the human can breath in, as if breathing air through the mouth, and thus expect water to flow in instead of air… (breathing in is really the atmospheric pressure pushing in too…) and then with a mouth full of fluid, stop the air flow to the lungs and thus swallow the fluid into the oesophagus …
It sure feels like my cat is sucking on me while he’s kneading / digging his rotten claws into me. I mean, his mouth is clamped on my arm, I physically have to pry him off (painful) and there is much slobber afterward. That’s not sucking?
I have read before that they are incapable of creating the negative pressure needed to have atmospheric pressure force fluid up into their mouths, and thus use their tongue to throw it into their mouth. This presents the question then of how they breathe. I suspect the difference is that we are able to consciously close off the passage to our nose and have all the negative pressure directed through the mouth that is in contact with the water, and that other animals are not capable of this. If they try to suck things in, they just breathe in through their nose. Note that this implies it is impossible to suck things directly into your stomach (unless you’re like a certain carnival performer who could hold maybe a gallon of water in his stomach and squirt it back out; being able to push it out suggests he could pull it in as well, although I don’t know as I don’t remember who it was), you suck it in to your mouth, then stop the building of negative pressure in your lungs and switch your throat from your trachea to your esophagus before swallowing. That is, you can’t take long and sustained sips from a straw like you might do circle-breathing, because the fluid belongs in a different place in your body than the organ that is generating the pressure difference.
I tried (so can you!) “sucking” (initiating a fish face) using varying strengths of muscle pull on my cheeks; muscle pull being the “tactile” stress effected. I also tried doing a lip push–clenching your lips outward for an exaggerated kiss, which is part of the fish face. You can do both, repeatedly, if you concentrate, without creating air suction from the residual air in the mouth.
So that’s a suck.
BTW, just learned about the Galant reflex of the newborn–never thought of that adjective with one before.
