CLOSE

IQ-tips: Bottle Breakdown

I first moved to NYC in the summer of "˜91. The only thing anyone recycled in my neighborhood at the time were jokes about the Mets starting rotation.

But that all changed quite quickly, thanks to the Mobro 4000, that famous barge that hauled trash from New York to Belize and back in 1987 before some genius in Brooklyn figured out how to incinerate it.

The event captured the nation's attention and garbage became a hot issue in the late "˜80s and early "˜90s. In 1988, Resin Identification Codes started to appear on the bottom of plastic bottles classifying each by polymer type, which made it easier for them to be sorted for recycling.

But did you know the same number can help you determine which bottles are safe for drinking and which aren't? Lately, plastics numbered 3, 6, and 7 have come under scrutiny because of suspicions that they may leach harmful chemicals into whatever it is you happen to be drinking. So if you want to be extra cautious, aluminum or stainless steel might be a better choice at the gym. Otherwise, check the number on the bottom and make sure you've got the non-leaching 1, 2, 4, or 5 type.

For those curious about the polymers behind the number, Wiki has a handy chart that, excuse the pun "“ breaks them all down.

nextArticle.image_alt|e
arrow
video
Bone Broth 101
5669938080001

Whether you drink it on its own or use it as stock, bone broth is the perfect recipe to master this winter. Special thanks to the Institute of Culinary Education

nextArticle.image_alt|e
iStock
arrow
science
Why Can Parrots Talk and Other Birds Can't?
iStock
iStock

If you've ever seen a pirate movie (or had the privilege of listening to this avian-fronted metal band), you're aware that parrots have the gift of human-sounding gab. Their brains—not their beaks—might be behind the birds' ability to produce mock-human voices, the Sci Show's latest video explains below.

While parrots do have articulate tongues, they also appear to be hardwired to mimic other species, and to create new vocalizations. The only other birds that are capable of vocal learning are hummingbirds and songbirds. While examining the brains of these avians, researchers noted that their brains contain clusters of neurons, which they've dubbed song nuclei. Since other birds don't possess song nuclei, they think that these structures probably play a key role in vocal learning.

Parrots might be better at mimicry than hummingbirds and songbirds thanks to a variation in these neurons: a special shell layer that surrounds each one. Birds with larger shell regions appear to be better at imitating other creatures, although it's still unclear why.

Learn more about parrot speech below (after you're done jamming out to Hatebeak).

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios