Photo via Bruce McAdams/Flickr
The notion of a baby being "raised by wolves" mildly distresses me, because let's be honest, doesn't a baby look a lot more like a wolf meal than a wolf pup? But what if someone was raised by lemurs, our fellow primates? There might be some latent potential deep down in child development there: A baby’s brain lights up at the sound of the human voice, but an infant’s attention can also be triggered by the blue-eyed lemur.
According to a new study by researchers at Northwestern University, it takes time for babies to figure out just which species they should be tuning into. “At birth, infants prefer listening to vocalizations of human and nonhuman primates; within 3 months, this initially broad listening preference is tuned specifically to human vocalizations,” the study states.
After the age of 6 months, babies lose their sensitivity to the other primates and identify with humans. But, until then, researchers found babies' brains don't even respond to the sound of human speech played backwards as well as they respond to lemurs. The sound clip of a terrifying lemur screetch really drives home how weird this is.
It's fascinating how fast the brain changes in the first year. After learning to filter out other primates at 6 months, infants start to lose the ability to distinguish between sounds that don't appear in the baby's native language at 9-12 months.
To my much older-than-six-month ears, lemurs don’t sound much like people, so much as tornado sirens, so I find the results extra-interesting. Here's the accompanying audio, if you'd like to compare.
So that's the lemur obiviously. Here's the human speech played backward.
So, the human speech doesn't sound normal, but lemurs sort of sound terrifying. Were these babies rightfully terrified? Or did they want to join the ranks of lemurs? And amongst lemurs, which do babies prefer?
If you have a baby, here are some videos to try out:
These ring-tailed lemurs sound like fairly obnoxious people in a horrible choir:
The Indri lemur sounds like a clarinet being mangled:
These red-ruffled lemurs sound like a broken-down car trying to turn over and look like Martin Van Buren if he was a dog:
These are the blue-eyed black lemurs that make unsettling alien sounds. You can’t really blame babies for paying attention to them. Also they (the lemurs) look like adorable monsters:
The kicker for this study was reported by NBC, which noted that, “a second study at this lab is investigating whether babies can retain their ability to engage with lemur calls and human voices, if their parents play them the lemur calls at bedtime every day.” We can only hope that this bridges the species gap.