C-Sections May be Altering the Course of Human Evolution
In some countries at least, the “obstetrical dilemma” has been solved by modern medicine.
Caesarean sections have been performed for hundreds of years. Although named for the Roman Emperor, there is no evidence he was actually born this way. Traditionally, the procedure was performed in cases where the mother was dying, in order to save the child’s life. Today, around one-third of US births are C-sections.
While in some instances, the mother cannot deliver the baby normally without risk to her or the infant, those children born naturally have stronger immune systems, and a lower chance of obesity. This is perhaps due to picking up crucial bacteria from the mother’s microbiome while moving through the birth canal. Now, a new study finds that the prevalence of this procedure has even greater complications, not just for the individual, but for the entire human race.
One of the issues C-sections solve is mothers with narrow pelvises. Human children are actually born prematurely compared to other mammals. That’s because our large brain cases become too big to pass through a narrow birth canal. Unfortunately, evolution hasn’t changed the female pelvis all that much, while infants have become larger. Larger babies have a higher rate of survival. At the same time, women’s pelvises have become smaller over time to aid bipedal locomotion and limit premature birth.
The problem revolves around what is known as the obstetrical dilemma. From an evolutionary standpoint, the need for walking upright is fighting against the need to be able to accommodate a child during birth. The rise in C-sections has given locomotion the upper hand. As a result of the rapid increase in C-sections in the last few decades, those mothers with narrow pelvises are more likely to pass on their genes.
Cesarean section. By BruceBlaus: Blausen.com staff. "Blausen gallery 2014". Wikiversity Journal of Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762. (Own work) [CC BY 3.0] via Wikimedia Commons
Theoretical biologist Philipp Mitteroecker was the lead researcher in this study, which looked at the effects of rising C-sections on human evolution. Mitteroecker is an assistant professor at the University of Vienna. "Our intent is not to criticize medical intervention,” he said, “but it's had an evolutionary effect.” Instances where the child cannot make it down the birth canal have increased globally. The rate went from 30 in 1,000 births in the 1960s to 36 in 1,000 today. In other words, worldwide, the rate was 3% globally in the 1960s, and now it is 3.6%, an increase of 10-20%. That’s a significant change in a very short period of time.
The study first began when Mitteroecker and colleagues wondered about fetopelvic disproportion – the condition where the baby doesn’t fit through the birth canal. Why was the rate of this condition so high worldwide? To find out, they constructed a mathematical model and fed it obstructed childbirth data obtained from the World Health Organization (WHO).
Dr. Briana Pobiner is a paleoanthropologist at The Smithsonian. She told the BBC that these findings aren’t exactly uniform globally. The practice of cesarean birth varies in different countries and cultures throughout the world. Other experts pointed out health-related factors such as higher obesity and diabetes rates. Birth by C-section is less risky for those with such metabolic conditions.
Besides more women with narrow pelvises, larger babies may also be an evolutionary trend. Though all of this sounds worrying, Mitteroecker and colleagues say it doesn’t spell the end of natural childbirth. However, they do believe this upward trend in the number of C-sections worldwide is likely to continue, albeit slowly. More studies will have to be conducted to verify the relationship between the uptick in C-sections and the effects on natural selection. Dr. Mitteroecker and colleagues hope this sparks a debate surrounding how and when a cesarean should be performed. According to the WHO, 10-15% of all births should be delivered in this manner.
To learn more about the impact of C-sections and other aspects of women’s health, click here:
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Welcome to the world's newest motorsport: manned multicopter races that exceed speeds of 100 mph.
- Airspeeder is a company that aims to put on high-speed races featuring electric flying vehicles.
- The so-called Speeders are able to fly at speeds of up to 120 mph.
- The motorsport aims to help advance the electric vertical take-off and landing (eVTOL) sector, which could usher in the age of air taxis.
Credit: Airspeeder<p>To prevent crashes, Airspeeder is working with the companies Acronis and Teknov8 to develop "high-speed collision avoidance" systems for its Speeders.</p><p style="margin-left: 20px;">"As they compete, Speeders will utilise cutting-edge LiDAR and Machine Vision technology to ensure close but safe racing, with defined and digitally governed no-fly areas surrounding spectators and officials," Airspeeder wrote in a <a href="https://airspeeder.com/news/2020/9/7/airspeeder-worlds-first-flying-electric-car-racing-series-partners-with-cyber-protection-leader-acronis-34g4k" target="_blank">blog post</a>.</p>
Credit: Airspeeder<p>Beyond motorsports, Airspeeder hopes to help advance the electric vertical take-off and landing (eVTOL) sector. This sector is where companies like <a href="https://www.ainonline.com/aviation-news/business-aviation/2020-01-07/hyundai-and-uber-announce-evtol-air-taxi-partnership" target="_blank">Uber, Hyundai</a>, and Airbus are working to develop air taxis, which could someday take the ridesharing industry into the skies. By 2040, the autonomous urban aircraft industry could be worth $1.5 trillion, according to a <a href="https://www.morganstanley.com/ideas/autonomous-aircraft" target="_blank">2019 report</a> from Morgan Stanley.</p><p>Still, many technical and regulatory hurdles remain. Matt Pearson, Airspeeder's founder and CEO, thinks the futuristic motorsport will help to not only speed up that process, but also pave the way for self-driving cars.</p>
Astronomers spot an object heading into Earth orbit.
Minimoons<p>Scientists have confirmed just two prior minimoons. One was <a href="https://en.wikipedia.org/wiki/2006_RH120" target="_blank">2006 RH120</a>, which orbited us from September 2006 to June 2007. The other was <a href="https://en.wikipedia.org/wiki/2020_CD3" target="_blank">2020 CD3</a>, which got stuck in the 2015–2016 timeframe, and is believed to gotten away in May 2020.</p><p>2020 SO, the new kid on the block, is expected to arrive in October 2020 and pop out of orbit in May 2021.</p><div id="37962" class="rm-shortcode" data-rm-shortcode-id="f4c0fc8a2cba6536ea4cd960ebed3e6e"><blockquote class="twitter-tweet twitter-custom-tweet" data-twitter-tweet-id="1307729521869611008" data-partner="rebelmouse"><div style="margin:1em 0">Asteroid 2020 SO may get captured by Earth from Oct 2020 - May 2021. Current nominal trajectory shows shows capture… https://t.co/F5utxRvN6Z</div> — Tony Dunn (@Tony Dunn)<a href="https://twitter.com/tony873004/statuses/1307729521869611008">1600621989.0</a></blockquote></div>
Identifying 2020 SO<p>The first clue 2020 SO isn't your ordinary asteroid is its exceptionally low velocity. It's traveling much more slowly that a typical asteroid — their <a href="https://www.lpi.usra.edu/exploration/training/illustrations/craterMechanics/" target="_blank">average rate of travel</a> <a href="https://www.lpi.usra.edu/exploration/training/illustrations/craterMechanics/" target="_blank" rel="noopener noreferrer"></a>is 18 kilometers (58,000 feet) per second. Even <a href="https://en.wikipedia.org/wiki/Moon_rock" target="_blank">moon rocks</a> sent careening into Earth orbit by impacts on the lunar surface outpace pokey 2020 SO.</p><p>For another thing, 2020 SO has an orbital path very similar to Earth's, lasting about one Earth year. It's also just slightly less circular than our own orbit, from which it's barely tilted off-axis.</p><p>So, what is it? <a href="https://cneos.jpl.nasa.gov/ca/" target="_blank">NASA estimates</a> that the object has dimensions very reminiscent of a discarded Centaur rocket stage from the <a href="https://en.wikipedia.org/wiki/Surveyor_2" target="_blank" rel="noopener noreferrer">Surveyor 2 mission</a> that landed an unmanned craft on the moon. Back in the day, rocket stages were jettisoned as craft were aimed toward their desired position. This stuff, if released high enough, remains in space. It appears that this Centaur rocket, launched in September 1966, is now making its way back homeward, at least for a little bit.</p><p>When 2020 SO arrives at its closest point in December, the rocket is expected to be about 50,000 kilometers from Earth. Its next closest approach is much further: 220,000 kilometers, in February 2010.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQzMDk3NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyODg1MTQ1MX0.HGknDwqp0GmeuczKY_AS7vrPG7KMFUc_XO95tNoI2xo/img.jpg?width=980" id="e5cda" class="rm-shortcode" data-rm-shortcode-id="85eb1f790d8c3ee5b261f7ba13eaa5e1" data-rm-shortcode-name="rebelmouse-image" alt="Centaur rocket stage" />
Centaur rocket stage
What we may be able to learn<p>Earthly space programs being as young as they are, scientists would love to know what's happened to our rocket during a half century in space.</p><p>While 2020 SO won't get close enough to drop into our atmosphere, its slow progress has scientists hopeful that they'll still get some kind of a decent look at it.</p><p>Spectroscopy may be able to reveal what the rocket's surface is like now — has any of its paint survived, for example? Of course, being out in space, it's likely to have been hit by lots of dust and micrometeorites, so the current state of its surfaces is also of interest. Experts are curious to know how reflective the rocket is at this point, valuable information that can help planners of future long-term missions anticipate how well a craft out in space for extended periods will remain able to reflect sunlight.</p>
From cryonics to time travel, here are some of the (highly speculative) methods that might someday be used to bring people back to life.
- Alexey Turchin and Maxim Chernyakov, researchers belonging to the transhumanism movement, wrote a paper outlining the main ways technology might someday make resurrection possible.
- The methods are highly speculative, ranging from cryonics to digital reconstruction of individual personalities.
- Surveys suggest most people would not choose to live forever if given the option.
Immortality and identity<p>The paper defines life as a "continued stream of subjective experiences" and death as the permanent end of that stream. Immortality, to them, is a "life stream without end," and resurrection is the "continuation of that same stream of experiences after an arbitrarily long gap."</p><p>Another key clarification is the identity problem: How would you know that a downloaded copy of yourself really was going to be <em>you? </em>Couldn't it just be a convincing yet incomplete and fundamentally distinct representation of your brain?</p><p>If you believe that your copy is not <em>you</em>, that implies you believe there's something more to your identity than the (currently) quantifiable information contained within your brain and body, according to the researchers. In other words, your "informational identity" does not constitute your true identity.</p><p>In this scenario, there must exist what the researchers call a "non-informational identity carrier" (NIIC). This could be something like a "soul." It could be "qualia," which are the unmeasurable "subjective experiences which could be unique to every person." Or maybe it doesn't exist at all.</p><p>It's no matter: The researchers say resurrection, in some form, should be possible in either scenario.</p><p style="margin-left: 20px;">"If no 'soul' exist[s], resurrection is possible via information preservation; if soul[s] exist, resurrection is possible via returning of the "soul" into the new body. But some forms of NIIC are also very fragile and mortal, like continuity," the researchers noted.</p><p style="margin-left: 20px;">"The problem of the nature of human identity could be solved by future superintelligent AI, but for now it cannot be definitively solved. This means that we should try to preserve as much identity as possible and not refuse any approaches to life extension and resurrection even if they contradict our intuitions about identity, as our notions of identity could change later."</p>
Potential resurrection methods<p>Turchin and Chernyakov outline seven broad categories of potential resurrection methods, ranked from the most plausible to most speculative.<br></p><p>The first category includes methods practiced while the person is alive, like cryonics, plastination, and preserving brain tissue through processes like chemical fixation. The researchers noted that there have been "suggestions that the claustrum, hypothalamus, or even a single neuron is the neural correlate of consciousness," so it may be possible to preserve just that part of a person, and later implant it into another organism.</p><p>Other methods get far stranger. For example, one method includes super-intelligent AI that uses a <a href="https://en.wikipedia.org/wiki/Dyson_sphere#:~:text=A%20Dyson%20sphere%20is%20a,percentage%20of%20its%20power%20output." target="_blank">Dyson sphere</a> to harness the power of the sun to "power enormous calculation engines" that would "reconstruct" people who collected a sufficient amount of data on their identities.</p>
Turchin<p style="margin-left: 20px;">"The main idea of a resurrection-simulation is that if one takes the DNA of a past person and subjects it to the same developmental condition, as well as correcting the development based on some known outcomes, it is possible to create a model of a past person which is very close to the original," the researchers wrote.</p><p style="margin-left: 20px;">"DNA samples of most people who lived in past 1 to 2 centuries could be extracted via global archeology. After the moment of death, the simulated person is moved into some form of the afterlife, perhaps similar to his religious expectations, where he meets his relatives."</p><p>Delving further into sci-fi territory, another resurrection method would use time-travel technology.</p><p style="margin-left: 20px;">"If there will at some point be technology that allows travel to the past, then our future descendants will be able to directly save people dying in the past by collecting their brains at the moment of death and replacing them with replicas," the paper states.</p><p>How? Sending tiny robots back in time.</p><p style="margin-left: 20px;">"A nanorobot could be sent several billion years before now, where it could secretly replicate and sow nanotech within all living being[s] without affecting the course of history. At the moment of death, such nanorobots could be activated to collect data about the brain and preserve it somewhere until its future resurrection; thus, there would be no need for forward time travel."</p>
Pixabay<p>The paper <a href="https://www.academia.edu/36998733/Classification_of_the_approaches_to_the_technological_resurrection" target="_blank">goes on to outline some more resurrection methods</a>, including ones that involve parallel worlds, aliens, and clones, along with a good, old-fashioned possibility: God exists and one day he resurrects us. </p><p>In short, it's all extremely speculative.</p><p>But the aim of the paper was to catalogue known potential ways humans might be able to cheat death. For Turchin, that's not some far-off project: In addition to studying global risks and transhumanism, the Russian researcher heads the <a href="http://immortality-roadmap.com/" target="_blank">Immortality Roadmap</a>, which, similar to the 2018 paper, outlines various ways in which we might someday achieve immortality.</p><p>Although it may take centuries before humans come close to "digital immortality," Turchin believes that life-extension technology could allow some modern people to survive long enough to see it happen. </p><p>Want a shot at being among them? Beyond the obvious, like staying healthy, the Immortality Roadmap suggests you start collecting extensive data on yourself: diaries, video recordings, DNA information, EEGs, complex creative objects — all of which could someday be used to digitally "reconstruct" your identity.</p>But odds are you're not interested. Although Turchin and other scientists are bent on finding ways to avoid death and extend life indefinitely, <a href="https://www.theguardian.com/uk/2011/may/16/dying-still-taboo-subject-poll" target="_blank" rel="noopener noreferrer">surveys</a> <a href="https://quillette.com/2018/03/02/would-you-opt-for-immortality/" target="_blank" rel="noopener noreferrer">repeatedly</a> <a href="https://www.cbsnews.com/news/60-minutesvanity-fair-poll-the-afterlife/" target="_blank" rel="noopener noreferrer">show</a> that most people would not opt to live forever if given the choice.