How Nutritious Is That Fish? To Find Out, Ask Its Relatives
By Amy McDermott
Eels and anchovies don't look or act much alike. One is sinuous and shy, the other a bright flash of silver in a school of thousands. Yet the two fish are cousins, both loaded with zinc.
Related fish species—like eels and anchovies—have similar nutritional value, according to a new study in Nature Communications. Two fish can be wildly different on the outside but surprisingly similar on the inside, if they're close on the tree of life.
"There's a shared evolutionary history in the ocean," said food security scientist Bapu Vaitla, who co-led the new study at Harvard's T.H. Chan School of Public Health in Boston, with evolutionary biologist David Collar at Christopher Newport University in Newport News, Virginia.
Turns out, shared evolutionary history is a road map to the patterns of vitamins and minerals fanned through the tissues of fish worldwide. That's a juicy tidbit for researchers studying the links between fish and human health. The specific blend of nutrients in a fish determines how people are nourished when they eat that species.
More than 3 billion people depend on fish for about one-fifth of the animal protein they eat. It's a staple food in dozens of countries, that offers calories, protein, fats and essential micronutrients like iron, zinc, calcium and vitamin A.
Not all fish are the same, though. Cod is much lower in zinc than anchovies, while salmon and trout are fattier than flatfishes, and higher in vitamin D than mackerels. Each species has its characteristic mix of nutrients.
Knowing that mix tells scientists how fish nourish people. It's valuable information, but not cheap or easy work.
Analyzing the nutrient content of one tissue sample costs several hundred to several thousand dollars, said Oceana science adviser Chris Golden, who heads the Harvard research group responsible for the new study. It takes multiple samples, sometimes collected around the world, to build a complete nutrient profile for a species.
Nutrient profiles do exist for hundreds of fish species, but thousands are nutritionally important, Vaitla said. "We couldn't collect samples all over the world, so we needed to predict nutrient content somehow."
The species people eat can say a lot about global health. Oceana / Jon Dee
A Living Mosaic
The oceans are a patchwork of unevenly distributed nutrients. Vaitla and his research partners expected that fish with similar lifestyles, that develop in similar conditions and habitats, would probably be exposed to similar challenges and opportunities, and so be nutritionally alike.
But when the scientists looked across 371 food fish species, they found that body size, preferred habitat and other lifestyle characteristics were not good predictors of nutritional similarity. Instead, genetic relatedness turned out to be key.
"It's not totally unsurprising," said marine ecologist William Cheung of the University of British Columbia, in Vancouver, who was not involved in the new study. Evolutionary relationships click as predictors of nutrition, he said. "Sometimes in science, when someone tells you the answer, you think, ah yes, that's true, that makes sense."
Yet, Cheung said, if he had undertaken the same research, he would've tested lifestyle characteristics first, too. He and Vaitla were both surprised that body size, habitat and other lifestyle characteristics didn't seem to play a role. Vaitla hasn't ruled them out. Repeating the study with more species of fish, he said, could reveal a pattern between lifestyle characteristics and nutrition in the future.
Food for Thought
That related fish are nutritionally similar may not be surprising, but it is useful. Scientists can now predict the vitamin and mineral content of fish species without tissue samples, based instead on their evolutionary relationships.
Predictions could come in especially handy now, as many marine species relocate in response to global change. As they move, they carry their distinct mix of vitamins and minerals with them, exposing fishermen and coastal people to a new mix of nutrients in the fish they eat. When new species move in, they may have different nutritional value from the old staples, exposing communities to risk of malnutrition.
"When we're worried about things like climate change or pollution or overfishing and how its affecting human health, the question amounts to knowing the nutrient landscape out there and how these environmental changes alter that landscape," Vaitla said. "If we're able to know that, we can say things like climate change will impact the availability of iron to this extent, and for these people."
To avoid anticipated risks, communities might curb commercial fishing or set aside marine protected zones, Vaitla said. But first, they need a way to see what's coming. "Evolutionary history," he said, "gives us a shortcut to paint the nutrient landscape out there."
By Victoria Masterson
Using one of the world's problems to solve another is the philosophy behind a Norwegian start-up's mission to develop affordable housing from 100% recycled plastic.
Sustainable Homes<p>UN-Habitat says an <a href="https://unhabitat.org/un-habitat-aims-to-use-plastic-waste-to-support-housing-for-all" target="_blank">estimated 60% of people living in urban areas of Africa are in informal settlements</a>. At the same time, between 1990 and 2017, African countries imported around 230 metric tonnes of plastic, "which mostly ended up in dump sites creating a massive environmental challenge," the agency adds.</p><p>UN-Habitat deputy executive director, Victor Kisob, said the aim of the partnership with Othalo was to "promote adequate, sustainable and affordable housing for all."</p>
Artist's impression of an Othalo community, imagined by architect Julien De Smedt. Othalo<p>Othalo's process involves shredding plastic waste and mixing it with other elements, including non-flammable materials. Components are used to build up to four floors, with a home of 60 square metres using eight tons of recycled plastic. A factory with one production line can produce 2,800 housing units annually.</p><p>Following successful laboratory tests, Othalo's factory in Estonia has started producing components to build three demonstration homes for Kenya's capital, Nairobi; Yaoundé, the capital of Cameroon and Dakar, the capital of Senegal.</p><p>Othalo founder Frank Cato Lahti has been developing and testing the technology since 2016 in partnership with <a href="https://www.sintef.no/en/" target="_blank">SINTEF</a>, a 70-year-old independent research organization in Trondheim, Norway, and experts at Norway's <a href="https://en.uit.no/startsida" target="_blank" rel="noopener noreferrer">University of Tromsø</a>.</p>
Othalo founder Frank Cato Lahti. Othalo<p>Almost <a href="https://www.un.org/development/desa/publications/2018-revision-of-world-urbanization-prospects.html" target="_blank">seven out of every 10 people in the world are expected to live in urban areas by 2050</a>. More than 90% of this growth will take place in Africa, Asia, Latin America, and the Caribbean.</p><p>"In the absence of effective urban planning, the consequences of this rapid urbanization will be dramatic," UN-Habitat warns.</p><p>Lack of proper housing and growth of slums, inadequate and outdated infrastructure, escalating poverty and unemployment, and pollution and health issues, are just some of the effects.</p><p>Mindsets, policies, and approaches towards urbanization need to change for the growth of cities and urban areas to be turned into opportunities that will leave nobody behind, UN-Habitat says.</p>
Pioneers of Change<p>Reimagining cities and communities for greater resilience and sustainability was a key topic at the<a href="https://www.weforum.org/events/pioneers-of-change-summit-2020" target="_blank"> World Economic Forum's Pioneers of Change Summit 2020</a>.</p><p>The digital event brought together innovators and stakeholders from around the world to explore solutions to the challenges facing enterprises, governments and society.</p><p>Opening the summit, <a href="https://www.weforum.org/events/pioneers-of-change-summit-2020/sessions/opening-plenary-8f731cbc65" target="_blank">Stephan Mergenthaler, the Forum's Head of Strategic Intelligence and a member of the Executive Committee</a>, said: "We need to change the way we produce, the way we live and interact in our cities to make this transition to net-zero emissions a reality…</p><p>"And as this year has illustrated so dramatically, we need to make every effort that we keep populations healthy, if we want to avoid jeopardizing all this progress."</p><p><em>Reposted with permission from </em><em><a href="https://www.weforum.org/agenda/2020/11/un-africa-recycled-plastic-housing/" target="_blank">World Economic Forum</a>.</em><a href="https://www.ecowatch.com/r/entryeditor/2649069252#/" target="_self"></a></p>
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By Dolf Gielen and Morgan Bazilian
John Kerry helped bring the world into the Paris climate agreement and expanded America's reputation as a climate leader. That reputation is now in tatters, and President-elect Joe Biden is asking Kerry to rebuild it again – this time as U.S. climate envoy.
Energy Is at the Center of the Climate Challenge<p>The <a href="https://science2017.globalchange.gov/chapter/1/" target="_blank">effects of climate change</a> are already evident across the globe, from <a href="https://theconversation.com/100-degrees-in-siberia-5-ways-the-extreme-arctic-heat-wave-follows-a-disturbing-pattern-141442" target="_blank">extreme heat waves</a> to <a href="https://science2017.globalchange.gov/chapter/12/" target="_blank">sea level rise</a>. But while the challenge is daunting, there is hope. Solar and wind power have become the <a href="https://www.irena.org/publications/2020/Jun/Renewable-Power-Costs-in-2019" target="_blank">cheapest forms of power generation globally</a>, and technology progress and innovation continue apace to support a transition to clean energy.</p><p>In the U.S. under a Biden administration, long-term national climate legislation will depend on who controls the Senate, and that won't be clear until after two run-off elections in Georgia in January.</p><p>But there is no shortage of <a href="https://www.bloomberg.com/features/2020-biden-climate-change-advice/" target="_blank">ideas for ways Biden</a> could still take action even if his proposals are blocked in Congress. For example, he could use executive orders and direct government agencies to tighten regulations on greenhouse gas emissions; increase research and development in clean energy technologies; and empower states to exceed national standards, <a href="https://www.reuters.com/article/us-autos-emissions-california/defying-trump-california-locks-in-vehicle-emission-deals-with-major-automakers-idUSKCN25D2CH" target="_blank" rel="noopener noreferrer">as California did in the past with auto emission standards</a>. A focus on a just and equitable transition for communities and people affected by the decline of fossil fuels will also be key to creating a sustainable transition.</p><p>The U.S. position as the world's largest oil and gas producer and consumer creates political challenges for any administration. U.S. forays into European energy security are often treated with suspicion. Recently, France blocked <a href="https://www.wsj.com/articles/frances-engie-backs-out-of-u-s-lng-deal-11604435609" target="_blank">a multi-billion dollar contract</a> to buy U.S. liquefied natural gas because of concerns about limited emissions regulations in Texas.</p><p>Strengthening cooperation and partnerships with like-minded countries will be critical to bring about a transition to cleaner energy as well as sustainability in agriculture, forestry, water and other sectors of the global economy.</p>
Creating a Global Sustainable Transition<p>How the world recovers from COVID-19's economic damage could help drive a lasting shift in the global energy mix.</p><p>Nearly one-third of Europe's US$2 trillion economic relief package <a href="https://www.bloomberg.com/news/articles/2020-07-21/eu-approves-biggest-green-stimulus-in-history-with-572-billion-plan" target="_blank" rel="noopener noreferrer">involves investments that are also good for the climate</a>. The European Union is also strengthening its 2030 climate targets, though each country's energy and climate plans will be critical for successfully implementing them. The <a href="https://joebiden.com/clean-energy/" target="_blank" rel="noopener noreferrer">Biden plan</a> – including a $2 trillion commitment to developing sustainable energy and infrastructure – is aligned with a global energy transition, but its implementation is also uncertain.</p><p>Once Biden takes office, Kerry will be joining ongoing <a href="https://www.un.org/en/conferences/energy2021/about#:%7E:text=The%20overarching%20goal%20of%20the,2030%20Agenda%20for%20Sustainable%20Development.&text=Accelerate%20delivery%20of%20United%20Nations,related%20issues%20at%20all%20levels." target="_blank" rel="noopener noreferrer">high-level discussions on the energy transition</a> at the U.N. General Assembly and other gatherings of international leaders. With the U.S. no longer obstructing work on climate issues, the G-7 and G-20 have more potential for progress on energy and climate.</p><p>Lots of technical details still need to be worked out, including international trade frameworks and standards that can help countries lower greenhouse gas emissions enough to keep global warming in check. <a href="https://www.carbonpricingleadership.org/what" target="_blank" rel="noopener noreferrer">Carbon pricing</a> and <a href="https://www.csis.org/analysis/how-can-europe-get-carbon-border-adjustment-right" target="_blank" rel="noopener noreferrer">carbon border adjustment taxes</a>, which create incentive for companies to reduce emissions, may be part of it. A consistent and comprehensive set of national energy transition plans will also be needed.</p><p>The global shift to <a href="https://www.irena.org/publications/2019/Jan/A-New-World-The-Geopolitics-of-the-Energy-Transformation" target="_blank">clean energy will also have geopolitical implications for countries and regions</a>, and this will have a profound impact on wider international relations. Kerry, with his experience as secretary of state in the Obama administration, and Biden's plan to make the climate envoy position part of the National Security Council, may help mend these relations. In doing so, the U.S. may again join the wider community of countries willing to lead.</p>
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By Maria Caffrey
As we approach the holidays I, like most people, have been reflecting on everything 2020 has given us (or taken away) while starting to look ahead to 2021.