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How Climate Change Shaped Human Migration Out of Africa

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Climate change has been shaping human existence for a long time. Researchers, who published their findings today, September 21, in the journal Nature, say our prehistoric ancestors dispersed across the globe in waves, inspired by dramatic changes in the world’s climate.

Exactly how and why our distant ancestors found their way through and out of Africa is the subject of much speculation and research. Earlier studies have concluded that Earth’s orbit caused natural and widespread climate changes in the Late Pleistocene epoch 126,000 to 11,000 years ago, and that these changes might have driven Homo sapiens to scatter and spread across the shifting continents.

To test this theory, researchers at the University of Hawaii at Manoa decided to look for clues in the planet’s climate. They created a computer simulation that tracked changes in life—sustaining elements like vegetation, glacier melt, sea level, and temperature—that could have forced humans to get up and go. 

Their results suggest that early humans did indeed spread in waves. In fact, there were distinct cycles of human exit from Africa, the most significant of which happened around 60,000 years ago, according to the data.

Study co-author Tobias Friedrich created this video depicting human dispersal and density from Africa throughout the world from 125,000 years to 1000 years ago. 

There was one unexpected finding: According to this model, around 80,000 years ago there was a small but rapid human migration into Europe. Unlike the rest of the model’s conclusions, this time estimate conflicts pretty significantly with the archaeological record, which puts the first modern people in Europe no earlier than 45,000 years ago.

William Harcourt-Smith is a paleoanthropologist at the American Museum of Natural History. He was not affiliated with the current study. “This sort of modelling, trying to think about the dispersal of modern humans across the globe in a truly biogeographical sense, is to be applauded,” he told mental_floss.

But Harcourt-Smith is not convinced by the new paper’s pushing back of the first human arrival in Europe by some 35,000 years. The evidence for the first entry occurring about 45,000 years ago is sound, he says: “We know this from the fossil record (modern humans look very different from late Pleistocene Neanderthals) and the distinct archaeological markers found only at modern human sites.”

While fascinating, he says, the new paper is “very, very speculative at best” and should be considered a jumping-off point for further research.

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Amsterdam is Turning Plastic Trash Into 3D-Printed Furniture
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PrintYourCity

The city of Amsterdam in the Netherlands is taking a unique approach to waste management, Inhabitat reports. Under the direction of The New Raw, a Rotterdam-based design studio, recycled plastic is being used to make public benches that capture a lot of the area’s charm while providing solutions for the 51 pounds of plastic refuse each Amsterdam resident tosses away each year.

The initiative is called Print Your City! and encourages those materials to be repurposed via 3D printing to make new, permanent fixtures. The New Raw calls it a “closed loop” of use, where the plastic is used, reused, and materialized in the same environment. The bench, dubbed XXX, seats two and rocks back and forth with the sitters' movements, offering a metaphor for the teamwork The New Raw is attempting to cultivate with the general public.

A plastic chair is surrounded by trash
Print Your City!

“Plastic has a major design failure,” says Panos Sakkas, an architect with The New Raw. “It’s designed to last forever, but it’s used only for a few seconds and then easily thrown away.”

The goal is to collect more plastic material in the city to use for projects that can be designed and implemented by citizens. In the future, 3D printing may also support bus shelters, waste bins, and playground material—all of it recyclable.

[h/t Inhabitat]

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To Encourage Responsible Trash Disposal, a Startup in Nigeria Pays People for their Waste
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Nigeria is home to more than 180 million people, who produce more than 32 million tons of waste per year and just 20 to 30 percent of this garbage is collected, according to one estimate. To provide Nigerians with incentive to dispose of their trash responsibly, Junks, a Nigerian waste management startup, provides people with the chance to exchange their trash for cash, according to Konbini.

The company offers to pay for items and materials like discarded electronics, glass, plastic, aluminum, books, and clothes. Once purchased, these materials are re-sold to wholesalers and recycling companies, according to Techpoint. Potential users who want to sell their trash are required to register on the startup's website, Junks.ng, and fill out a form with a description of the trash they're selling, along with their asking price and contact information. Once this information is received, representatives from Junks are sent to pick up and pay for the waste.

Computer programmer Bradley Yarrow founded Junks.ng in August 2017. Based in Port Harcourt, the capital of Rivers State, Nigeria, the company currently has just three employees, in addition to Yarrow. That said, the tiny startup appears to be doing big business, judging from a growing list of sold junk—which includes laminating machines, old laptops, and scrap car parts—already listed on Junks.ng.

[h/t Konbini]

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