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How many times can a piece of paper be recycled?

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The recycling logo "“ those three arrows going around in an endless loop "“ is lying to you. While glass and plastic can be recycled indefinitely (at least in theory for plastic, which is usually "upcycled" or "downcycled" into products that can't be recycled), paper only gets so many go-rounds through the circle of life.

On trash day, the paper in our recycling bins goes to a recycling center and then a paper mill, where it's put into vat called a pulper. The pulper, which also contains water and some chemicals, is essentially a giant blender and shreds the recovered paper into small pieces. The paper-liquid mixture is then heated so the paper breaks down into little fibers. The resulting mush is called pulp.

Contaminants are removed from the pulp by cleaning and screening. The pulp is cleaned in a spinning cone-shaped cylinder that separates heavy contaminants like staples. Screening is exactly what it sounds like. The pulp is forced through various screens to remove smaller contaminants like bits of glue.

Some recovered paper is de-inked, and some is not. De-inking can be done in two ways: washing or flotation. During washing, chemicals are added to the pulp to separate the ink from the paper fibers. The pulp is then rinsed with water and the ink is washed away. In the flotation method, the pulp is put in another water-filled vat called a flotation cell. Surfactants are used to loosen the ink from the pulp, and air is passed through the cell. The air bubbles float the ink to the top of the mixture and the resulting froth skimmed off the top.

The pulp is then beaten to separate large clumps of fibers and make the fibers swell so they're better suited for papermaking. At this point, if white recycled paper is being made, the pulp is also bleached to make it bright white (if brown recycled paper is being made, say, for industrial paper towels, the pulp doesn't get bleached).

To make the pulp back into paper, the recycled fibers are blended with new wood fiber (virgin fiber) to give it extra strength and mixed with water. A paper machine sprays the watery pulp in a wide jet onto a wire screen conveyor belt. As the pulp travels on the belt, water drains through the screen and the paper fibers begin to bond together. A series of press rollers squeeze out more water and heated metal rollers dry the paper, which, now finished, is wound into a roll that can be cut into smaller rolls or sheets.

Phew. As you can see, paper goes through quite a bit of abuse during the recycling process and each time recovered paper goes through the whole song and dance the individual wood fibers become shorter and more brittle and lose their strength. Paper industry folks say that the average paper fiber can survive recycling six to eight times before its short enough to slip away during the screening process.

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FRED TANNEAU/AFP/Getty Images
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Animals
Fisherman Catches Rare Blue Lobster, Donates It to Science
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FRED TANNEAU/AFP/Getty Images

Live lobsters caught off the New England coast are typically brown, olive-green, or gray—which is why one New Hampshire fisherman was stunned when he snagged a blue one in mid-July.

As The Independent reports, Greg Ward, from Rye, New Hampshire, discovered the unusual lobster while examining his catch near the New Hampshire-Maine border. Ward initially thought the pale crustacean was an albino lobster, which some experts estimate to be a one-in-100-million discovery. However, a closer inspection revealed that the lobster's hard shell was blue and cream.

"This one was not all the way white and not all the way blue," Ward told The Portsmouth Herald. "I've never seen anything like it."

While not as rare as an albino lobster, blue lobsters are still a famously elusive catch: It's said that the odds of their occurrence are an estimated one in two million, although nobody knows the exact numbers.

Instead of eating the blue lobster, Ward decided to donate it to the Seacoast Science Center in Rye. There, it will be studied and displayed in a lobster tank with other unusually colored critters, including a second blue lobster, a bright orange lobster, and a calico-spotted lobster.

[h/t The Telegraph]

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Courtesy Murdoch University
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Animals
Australian Scientists Discover First New Species of Sunfish in 125 Years
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Courtesy Murdoch University

Scientists have pinpointed a whole new species of the largest bony fish in the world, the massive sunfish, as we learned from Smithsonian magazine. It's the first new species of sunfish proposed in more than 125 years.

As the researchers report in the Zoological Journal of the Linnean Society, the genetic differences between the newly named hoodwinker sunfish (Mola tecta) and its other sunfish brethren was confirmed by data on 27 different samples of the species collected over the course of three years. Since sunfish are so massive—the biggest can weigh as much as 5000 pounds—they pose a challenge to preserve and store, even for museums with large research collections. Lead author Marianne Nyegaard of Murdoch University in Australia traveled thousands of miles to find and collected genetic data on sunfish stranded on beaches. At one point, she was asked if she would be bringing her own crane to collect one.

Nyegaard also went back through scientific literature dating back to the 1500s, sorting through descriptions of sea monsters and mermen to see if any of the documentation sounded like observations of the hoodwinker. "We retraced the steps of early naturalists and taxonomists to understand how such a large fish could have evaded discovery all this time," she said in a press statement. "Overall, we felt science had been repeatedly tricked by this cheeky species, which is why we named it the 'hoodwinker.'"

Japanese researchers first detected genetic differences between previously known sunfish and a new, unknown species 10 years ago, and this confirms the existence of a whole different type from species like the Mola mola or Mola ramsayi.

Mola tecta looks a little different from other sunfish, with a more slender body. As it grows, it doesn't develop the protruding snout or bumps that other sunfish exhibit. Similarly to the others, though, it can reach a length of 8 feet or more. 

Based on the stomach contents of some of the specimens studied, the hoodwinker likely feeds on salps, a jellyfish-like creature that it probably chomps on (yes, sunfish have teeth) during deep dives. The species has been found near New Zealand, Australia, South Africa, and southern Chile.

[h/t Smithsonian]

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