Why Are Infants So Loud?

I’ve noticed that infants have an innate ability to cry and scream at astonishingly high decibel levels. What is the reason for this ability?

As I understand it, our maternal ancestors generally kept their infants by their side under close watch. If this is correct, a slight whimper would be sufficient to signal that the child is hungry. This makes screaming at the top of your lungs appear to be counter-productive, as it wastes energy and could possibly alert predators.

So why are infants’ cries so loud?

Thanks.

WAG from personal experience, it is a form of negative reinforcement. When that baby is wailing loud, your dang right I am dropping everything and trying to figure out what is wrong as soon as possible, anything to turn off that siren! :wink: That loud cry lets me know that the baby is in distress to a higher degree. If they baby just wimpered (which they often do for no apparent reason), I might continue on with other tasks. In addition, people with babies have to sleep every once in a while. A loud cry gets you up and going where a wimper might be ignored.

Aye, there’s an evolutionary advantage to having a baby with lungs that can exceed local noise pollution bylaws.

Yes. Without them, who would grow up to be hog callers, drill sergeants, or operatic soloists?

Not to mention potential cell phone customers.

And this is precisely why law enforcement agencies have sirens on their vehicles which tend to hit the same frequencies as the cry of a baby. It’s deliberate. You wouldn’t leap to attention for a police car that was broadcasting a funky bass note, but you’re on instant alert when you hear that siren. It’s hardwired in us.

I’m afraid I don’t have a cite for that handy off the top of my head, but I’ve read of it multiple times.

I still think babies are nothing decibel-wise to a screaming ten year-old girl. I’ve heard some that I could’ve sworn were being tortured, but subsequently found out where merely playing.

I think **chriscya **hit it in one. Not all babies’ cries are loud, and not all of each baby’s cries are loud (if you see the distinction), but the ones that are are really annoying because they work.

Babies do do a whole lot of quiet whimpering, trilling, cooing and smiling to get their servant/parents to do their whim. When they do cry (barring colic, which no one can really explain) they have different cries of different pitches and irritant levels to communicate different things, all of which need pretty immediate attention: discomfort, hunger, boredom, sleepiness and pain. The loudest of these is the “pain” cry. This is the cry that, saber-toothed tiger bedamned, means the baby needs attention RIGHT NOW! And it’s so distressing for adults to hear that we cannot help but respond quickly, or suffer very real emotional and sometimes physical pain. If these needs are attended to, then the baby settles back down into quiet grousing, most of the time.

OTOH, I think you’ve perhaps made a erroneous assumption in your OP: a baby may have been *near *it’s mother at most times, but not always as near as you’d think. Prior to the invention of knots (as in, knotted fur, fabric or even vines or grasses to make a baby sling), a human mother would need to set the baby down to gather or prepare food, wipe after defecation, build a fire or any other of a number of basic survival tasks. Even with a mate to provide food for both of them, she’s got to do some things besides just lay there for 18 months holding an infant who can’t walk beside her. We face a very real dillemma, without fur for an infant to cling to and no pouch for our basically immobile offspring for a very long time. So even 10 feet away from her baby lying on the ground means the baby needs a louder form of communication than a babble.

OTOOH, once the sling was invented, crying was much, much less of a problem. Babies carried in slings with constant or near constant parental contact don’t cry very much. They spend most of their time in what’s called the “quiet alert” stage of consciousness. So some of what you experience with babies crying is because, once saber-toothed tigers were no longer an immanent threat, people developed all sorts of non-evolutionarily driven habits of baby raising, including separate beds, playpens, daycare and other convienences which parents find nice, but babies find distressing. So babies get bored more, and distressed because mommy isn’t near (they’re still wired to think the saber-toothed tiger will eat them if mommy’s not around to scare it away), and they cry more than they would if they were carried all the time. You’re not seeing a clear “in nature” picture of babies’ behavior any more.

So they need to cry if something’s really wrong, but don’t cry as much as you think if they’re attended to quickly. If there were once babies who literally cried all the time, rest assured they’ve been eaten and aren’t breeding.

I have read that young children seem so loud when they’re playing (and of course babies when they’re screaming their heads off) because we hear them better; we don’t hear best at adult conversational levels, we hear better in upper pitches, the human “emergency band”. So those little girls you hear playing aren’t really that loud; you just hear them better (and obviously that’s why sirens are at a similar pitch.) I’d find a cite but my brain is a little addled this morning and all I can find is hearing tests for kids and emergency equipment.

I concur - now that we’ve had kids that are past infancy, my wife and I think it’s so cute how softly little babies cry - volume-wise. The parents will be like “sorry she’s so loud, we hope it didn’t keep you awake.” We’re just thinking, man, that’s nothing!!

Also, as other posters mentioned, parents learn to distinguish the severity of need associated with various cries. To me, a cry that may even be low volume-wise, because the baby is so young, can still be more piercing if it hits that “emergency, I need you now, I’m being skinned alive and eaten” tone.

And the cry of a baby/child/toddler/kid who is in a tantrum/hyperventillating/chronic-pain is the worst, since then it is crying for crying’s sake - meaning virtually unconsolable.

Babies don’t naturally scream for attention- it is a learned behaviour. There is a scream reflex as seen at birth, but this is molded by its social and psychological surroundings. If a baby feels distressed and wants attention, it will scream louder and louder until it gets the attention it wants/needs.

Proof of the above:
1/ Babies of parents with no hearing attract attention by waving, moving and rocking, but do not learn to scream/cry/bawl for attention.
2/ Babies who are totally ignored become mute and withdrawn.

They learn that screaming gets no attention in either case.

Having a three and four year old, I am aware of how piercing the screaming is, but if handled well, then screaming is less stressful than it needs to be. :smiley: