Caterpillar found to eat shopping bags, suggesting solution to plastic pollution • Hacker News Board

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#221

Post by [deleted] » Mon, Apr 24, 2017, 10:04 PM UTC

greenshackle2 wrote: post #177

orthecreedence wrote: post #135

Earlier quoted context omitted.

Every time I advocate for animal rights on this forum, it's met with downvotes and people huffing and puffing about the benefit to humanity and science. Your argument is sound...flies are animals. They have exoskeletons, six legs, and compound eyes but they are animals nonetheless. However, our cultural "worth" of flies is much lower than that of dogs, so even people who supposedly value logic above all else would ra…

Do you have a fully-coherent, logical system for deciding which lives to care about, and how much? I'd be interested to hear. 'Animals' is not a natural kind. There's no logical reason to care about all animals just because they are animals. I care about dogs, pigs, other people, etc. not because they're 'animals', but because I think they are plausibly conscious (to varying degrees) and they can experience joy and s…

[deleted]

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#222

Post by Houshalter » Mon, Apr 24, 2017, 10:15 PM UTC

jacquesm wrote: post #45

smueller1234 wrote: post #32

Earlier quoted context omitted.

Maybe the antithesis to the discovery of antibiotics is the mostly accidental discovery of Tabun: "In January 1937, Schrader observed the effects of nerve agents on human beings first-hand when a drop of tabun spilled onto a lab bench." (Wikipedia) I think that one might stand out somewhat since I'd expect most accidental advances to be helpful to humanity. Or maybe I'm just an optimist. :)

Scientists that voluntarily work to bring such stuff in the world are amongst the people I least respect. It's one thing to be dumb, quite another to be extraordinarily gifted and to use that gift to do something which has no upside at all and plenty of downside. Exposing them to their own creations would be poetic justice.

Many of the greatest physicists of that generation worked on atomic bombs. And even more were involved in other military technologies. What are you supposed to do, not give your country the best tools possible? Hope the other side is just really nice and does likewise? Risk your country getting conquered? Your family getting killed?

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#223

Post by matz1 » Mon, Apr 24, 2017, 10:17 PM UTC

mikeash wrote: post #162

sillysaurus3 wrote: post #111

Earlier quoted context omitted.

I try not to kill flies, no. The only exception is for multiple flies that won't go away. Ditto for ants. It's a bit strange that violence toward insects is fine, but violence towards dogs is not. Ever killed a dog because it annoyed you? That said, doing it for science at least has a justification.

It's because insects have such a primitive nervous system that we don't see them as being aware in the same way that a dog is. You draw the line somewhere , right? Drawing the line at a certain complexity of the nervous system is more sensible than drawing it at "animals" in general, IMO.

I draw the line at Human and Not Human.

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#224

Post by eric_h » Mon, Apr 24, 2017, 10:20 PM UTC

myegorov wrote: post #131

In my experience, common clothes moth[1] or its larvae is also capable of eating through a plastic bag enclosing dry foodstuffs or cereal. Not sure if they're actually digesting it or could survive on the polyethylene diet though. [1] https://en.wikipedia.org/wiki/Tineola_bisselliella

This is somewhat orthogonal to your point, but my cats are also perfectly capable of eating through a plastic bag enclosing dry foodstuffs (left a sealed bag of cat treats on the counter one day, found it chewed through and empty the next).

It does seem likely to me, however, that the number of insect species capable of eating through plastics and also breaking the plastic molecules down must surely number greater than one.

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#225

Post by monocasa » Mon, Apr 24, 2017, 10:24 PM UTC

mikeash wrote: post #162

sillysaurus3 wrote: post #111

Earlier quoted context omitted.

I try not to kill flies, no. The only exception is for multiple flies that won't go away. Ditto for ants. It's a bit strange that violence toward insects is fine, but violence towards dogs is not. Ever killed a dog because it annoyed you? That said, doing it for science at least has a justification.

It's because insects have such a primitive nervous system that we don't see them as being aware in the same way that a dog is. You draw the line somewhere , right? Drawing the line at a certain complexity of the nervous system is more sensible than drawing it at "animals" in general, IMO.

I mean, ants have passed the mirror test.

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#226

Post by Houshalter » Mon, Apr 24, 2017, 10:24 PM UTC

riskable wrote: post #193

rmason wrote: post #173

There's already a much better solution to deal with plastic pollution, a naturally degradable material made from corn. We heavily subsidize both wind power and solar. We even still subsidize gasohol even though it doesn't produce the environmental benefits we first thought that it did. But we don't subsidize degradable plastic made from corn which isn't used widely because it costs a few cents more than plastic made…

You are grossly oversimplifying the issues. You're referring to Polylactic Acid (PLA) which is made from corn and biodegradable. Except it only biodegrades when eaten by bacteria that only lives in soil . Meaning: If plastic made from PLA ends up in waterways, the oceans, etc it won't degrade there and actually just breaks down into smaller parts creating the exact same sort of problem as microbeads (except PLA doesn…

Subsidies to corn farmers don't go to bioplastic producers. Corn husks aren't exactly a scarce resource and would otherwise be left rotting in the field.

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#227

Post by Godel_unicode » Mon, Apr 24, 2017, 10:27 PM UTC

freeflight wrote: post #201

Eleopteryx wrote: post #180

Earlier quoted context omitted.

>You draw the line somewhere, right Yeah, I just have to worry about higher beings justifying the termination of my primitive nervous system "for science". Perhaps my consciousness is so dim relative to theirs that it would be analogous to me squashing a bug. I hope that their methods are advanced enough that they don't need to.

>Yeah, I just have to worry about higher beings justifying the termination of my primitive nervous system "for science". They might as well just terminate your primitive nervous system for their own nutritional needs or out of mere hunting instinct. Plenty of animals do this all the time, nature isn't romantic idealistic, it's ruthless and unforgiving.

Or alternatively, beautifully efficient.

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#228

Post by eric_h » Mon, Apr 24, 2017, 10:30 PM UTC

giarc wrote: post #13

Symbiote wrote: post #5

Earlier quoted context omitted.

"The analysis showed the worms transformed the polyethylene into ethylene glycol, representing un-bonded 'monomer' molecules." Moderately toxic, but breaks down in the air in about 10 days. Used in antifreeze. https://en.wikipedia.org/wiki/Ethylene_glycol

Interesting... is this why I've never heard any issues with the amount of windshield washer fluid that is used? I got through many litres every winter.

> windshield washer fluid that is used? I got through many litres every winter

You must be Canadian ;) I'm an expat of sorts and once went on a ski trip (from New Jersey to Mont Tremblant in Quebec) with a friend and his parents in January many years ago.

Long story short, we discovered shortly after hitting an ice storm (and finding the wiper fluid reservoir empty) in upstate New York that the wiper fluid reservoir in the car had a large crack in it such that after filling it would only work for about 5 minutes.

This ended up requiring someone to manually fill a cup with wiper fluid and throw it out the window onto the windshield every few minutes for several hours. That being a terribly inefficient delivery system, we went through many litres in one trip!

Not the most fun road trip I've ever been on, but the skiing was great when we (eventually) got there!

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#229

Post by PerfectElement » Mon, Apr 24, 2017, 10:31 PM UTC

matz1 wrote: post #223

mikeash wrote: post #162

Earlier quoted context omitted.

It's because insects have such a primitive nervous system that we don't see them as being aware in the same way that a dog is. You draw the line somewhere , right? Drawing the line at a certain complexity of the nervous system is more sensible than drawing it at "animals" in general, IMO.

I draw the line at Human and Not Human.

Any objective justification for that or just your own bias?

Re: Caterpillar found to eat shopping bags, suggesting solution to plastic pollution

#230

Post by Houshalter » Mon, Apr 24, 2017, 10:40 PM UTC

ars wrote: post #42

It makes sense that eventually things would eat plastic. Lignin (wood) and cellulose are pretty tough to break down, but there are things that eat them. Plastic fundamentally (chemically) is made of the same stuff as wood, just in a different arrangement of atoms, and releases energy when decomposed. So it seems quite reasonable that there would be things that can eat it. I think the plastic pollution we are seeing r…

These caterpillars didn't evolve to eat plastic as far as we know. Evolution takes place on unimaginably slow timescales. It took tens of millions of years for things to evolve to eat wood. Probably these caterpillars already happened to produce a chemical that reacts with plastic. I wonder if they even get any nutritional value from it.

That said, bacteria can evolve pretty fast because of high population sizes and low generation times. In the 50's they found a bacteria that had evolved to digest the synthetic material nylon. I wonder why bacteria haven't evolved to digest plastic yet. Possibly there is some scientific reason that it's inefficient to digest. Maybe we could speed evolution up by dissolving plastic in a liquid first so it's more accessible to them.