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Evolution: That famous ‘march of progress’ image is just wrong
Some fish evolved legs and walked onto the land. Right?
Evolution explains how all living beings, including us, came to be. It would be easy to assume evolution works by continuously adding features to organisms, constantly increasing their complexity.
Some fish evolved legs and walked onto the land. Some dinosaurs evolved wings and began to fly. Others evolved wombs and began to give birth to live young.
Yet this is one of the most predominant and frustrating misconceptions about evolution. Many successful branches of the tree of life have stayed simple, such as bacteria, or have reduced their complexity, such as parasites. And they are doing very well.
In a recent study published in Nature Ecology and Evolution, we compared the complete genomes of over 100 organisms (mostly animals), to study how the animal kingdom has evolved at the genetic level. Our results show that the origins of major groups of animals, such as the one comprising humans, are linked not to the addition of new genes but to massive gene losses.
The evolutionary biologist Stephen Jay Gould was one of the strongest opponents of "the march of progress", the idea that evolution always results in increased complexity. In his book Full House (1996), Gould uses the model of the drunkard walk. A drunkard leaves a bar in a train station and clumsily walks back and forth over the platform, swinging between the bar and the train tracks. Given enough time, the drunkard will fall in the tracks and will get stuck there.
The platform represents a scale of complexity, the pub being the lowest complexity and the tracks the maximum. Life emerged by coming out of the pub, with the minimum complexity possible. Sometimes it randomly stumbles towards the tracks (evolving in a way that increases complexity) and other times towards the pub (reducing complexity).
No option is better than the other. Staying simple or reducing complexity may be better for survival than evolving with increased complexity, depending on the environment.
But in some cases, groups of animals evolve complex features that are intrinsic to the way their bodies work, and can no longer lose those genes to become simpler - they become stuck in the train tracks. (There are no trains to worry about in this metaphor.) For example, multicellular organisms rarely go back to become unicellular.
If we only focus on the organisms trapped in the train tracks, then we have a biased perception of life evolving in a straight line from simple to complex, mistakenly believing that older lifeforms are always simple and newer ones are complex. But the real path to complexity is more tortuous.
Together with Peter Holland from the University of Oxford, we looked into how genetic complexity has evolved in animals. Previously, we have shown that the addition of new genes was key to the early evolution of the animal kingdom. The question then became whether that was the case during the later evolution of animals.
Studying the tree of life
Most animals can be grouped into major evolutionary lineages, branches on the tree of life showing how the animals alive today evolved from a series of shared ancestors. In order to answer our question, we studied every animal lineage for which a genome sequence was publicly available, and many non-animal lineages to compare them against.
One animal lineage is that of the deuterostomes, which includes humans and other vertebrates, as well as sea stars or sea urchins. Another is the ecdysozoans, comprising the arthropods (insects, lobsters, spiders, millipedes), and other moulting animals such as roundworms. Vertebrates and insects are considered some of the most complex animals. Finally, we have one lineage, the lophotrochozoans, that includes animals such as molluscs (snails, for example) or annelids (earthworms), among many others.
We took this diverse selection of organisms and looked to see how they were related on the tree of life and what genes they shared and didn't share. If a gene was present in an older branch of the tree and not in a younger one, we inferred that this gene had been lost. If a gene wasn't present in older branches but appeared in a younger branch, then we considered it a novel gene that had been gained in the younger branch.
The results showed unprecedented numbers of genes lost and gained, something never seen before in previous analyses. Two of the major lineages, the deuterostomes (including humans) and the ecdysozoans (including insects), showed the largest number of gene losses. In contrast, the lophotrochozoans show a balance between gene novelties and losses.
Our results confirm the picture given by Stephen Jay Gould by showing that, at the gene level, animal life emerged by leaving the pub and making a large leap in complexity. But after the initial enthusiasm, some lineages stumbled closer to the pub by losing genes, while other lineages drifted towards the track by gaining genes. We consider this the perfect summary of evolution, a booze-induced random choice between the bar and the train track. Or, as the internet meme says, "go home evolution, you are drunk".
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Innovation in manufacturing has crawled since the 1950s. That's about to speed up.
Here's why you might eat greenhouse gases in the future.
- The company's protein powder, "Solein," is similar in form and taste to wheat flour.
- Based on a concept developed by NASA, the product has wide potential as a carbon-neutral source of protein.
- The man-made "meat" industry just got even more interesting.
Seriously sustainable<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTk0MDIzNS9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTYyMjM4NTMzMX0.BCEfYnn6C3z1zUHIS38xOWjXktgamNBi5iyqklSMYK8/img.png?width=980" id="ea524" class="rm-shortcode" data-rm-shortcode-id="50533380eeb18eb5833b6b6aa3abec38" data-rm-shortcode-name="rebelmouse-image" />
Image source: Solar Foods<p>Solar Foods makes Solein by extracting CO₂ from air using <a href="https://www.fastcompany.com/90356326/we-have-the-tech-to-suck-co2-from-the-air-but-can-it-suck-enough-to-make-a-difference" target="_blank">carbon-capture technology</a>, and then combines it with water, nutrients and vitamins, using 100 percent renewable solar energy from partner <a href="https://www.fortum.com" target="_blank">Fortum</a> to promote a natural fermentation process similar to the one that produces yeast and lactic acid bacteria.</p><p>When the company claims its single-celled protein is "free from agricultural limitations," they're not kidding. Being produced indoors means Solar Foods is not dependent on arable land, water (i.e., rain), or favorable weather.</p><p>The company is already working with the European Space Agency to develop foods for off-planet production and consumption. (The idea for Solein actually began at NASA.) They also see potential in bringing protein production to areas whose climate or ground conditions make conventional agriculture impossible.</p><p>And let's not forget all those <a href="https://www.bk.com/menu-item/impossible-whopper" target="_blank">beef-free burgers</a> based on pea and soy proteins currently gaining popularity. The environmental challenge of scaling up the supply of those plants to meet their high demand may provide an opening for the completely renewable Solein — the company could provide companies that produce animal-free "meats," such as <a href="https://www.beyondmeat.com/products/" target="_blank">Beyond Meat</a> and <a href="https://impossiblefoods.com" target="_blank">Impossible Foods</a>, a way to further reduce their environmental impact.</p>
The larger promise<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTk0MDI0MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NjU4MTg2OX0.7dZZYT5WEV_EupBuLVFwHynarTiz8RYR9aJtC6Ts2C4/img.jpg?width=980" id="3415d" class="rm-shortcode" data-rm-shortcode-id="2e6eebe06d795f844752f9e9d30040d7" data-rm-shortcode-name="rebelmouse-image" />
Image source: Solar Foods<p>The impact of the beef — and for that matter, poultry, pork, and fish — industries on our planet is widely recognized as one of the main drivers behind climate change, pollution, habitat loss, and antibiotic-resistant illness. From the cutting down of rainforests for cattle-grazing land, to runoff from factory farming of livestock and plants, to the disruption of the marine food chain, to the overuse of antibiotics in food animals, it's been disastrous.</p><p>The advent of a promising source of protein derived from two of the most renewable things we have, CO₂ and sunlight, <a href="https://solarfoods.fi/environmental-impact/" target="_blank">gets us out of the planet-destruction business</a> at the same time as it offers the promise of a stable, long-term solution to one of the world's most fundamental nutritional needs.</p>
Solar Foods' timetable<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTk0MTEzMS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTU5OTU1OTMwMn0.wnXh56iO_77x2XKV2uIPf78BKw4AJLUpmiyq_JBVGvo/img.jpg?width=1245&coordinates=172%2C146%2C62%2C135&height=700" id="0297c" class="rm-shortcode" data-rm-shortcode-id="125c9a98ec818f5c241fa28ef1423e67" data-rm-shortcode-name="rebelmouse-image" />
Image source: Lubsan / Shutterstock / Big Think<p>While company plans are always moderated by unforeseen events — including the availability of sufficient funding — Solar Foods plans a global commercial rollout for Solein in 2021 and to be producing two million meals annually, with a revenue of $800 million to $1.2 billion by 2023. By 2050, they hope to be providing sustenance to 9 billion people as part of a $500 billion protein market.</p><p>The project began in 2018, and this year, they anticipate achieving three things: Launching Solein (check), beginning the approval process certifying its safety as a Novel Food in the EU, and publishing plans for a 1,000-metric ton-per-year factory capable of producing 500 million meals annually.</p>
The protein powder Solein. Image source: SOLAR FOODS
SEAL training is the ultimate test of both mental and physical strength.
- The fact that U.S. Navy SEALs endure very rigorous training before entering the field is common knowledge, but just what happens at those facilities is less often discussed. In this video, former SEALs Brent Gleeson, David Goggins, and Eric Greitens (as well as authors Jesse Itzler and Jamie Wheal) talk about how the 18-month program is designed to build elite, disciplined operatives with immense mental toughness and resilience.
- Wheal dives into the cutting-edge technology and science that the navy uses to prepare these individuals. Itzler shares his experience meeting and briefly living with Goggins (who was also an Army Ranger) and the things he learned about pushing past perceived limits.
- Goggins dives into why you should leave your comfort zone, introduces the 40 percent rule, and explains why the biggest battle we all face is the one in our own minds. "Usually whatever's in front of you isn't as big as you make it out to be," says the SEAL turned motivational speaker. "We start to make these very small things enormous because we allow our minds to take control and go away from us. We have to regain control of our mind."
Pandemic-inspired housing innovation will collide with techno-acceleration.