Writing a science fiction story…

involves imagining something you cannot possibly experience but facilitating the reader’s ability to suspend their belief and take the journey with you. Science fiction is a genre I have read but not on a scale that could put me in a room for a discussion with a devoted Trekkie, for example, or a Star Wars’ pundit, for that matter. I’ve seen a few movies like Fritz Lang’s Metropolis, Robert Wise’s The Day the Earth Stood Still and others. In fact, I was surprised to find I have seen no less than 72 of Time Out‘s Top 100 science Fiction films.

One thing the best of these films has is the ability to take you into those worlds and for that, well, you have to have the imagination to believe anything is possible. In Starman, there is life on another planet, human life. That creates problems for the writer about how did they get there, how do they survive and beyond surviving, how do they forge a future for themselves in such an alien environment.

Artificial wombs: The coming era of motherless births?

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Scientifically, it’s called ectogenesis, a term coined by J.B.S. Haldane in 1924. A hugely influential science popularizer, Haldane did for his generation what Carl Sagan did later in the century. He got people thinking and talking about the implications of science and technology on our civilization, and did not shy away from inventing new words in order to do so. Describing ectogenesis as pregnancy occurring in an artificial environment, from fertilization to birth, Haldane predicted that by 2074 this would account for more than 70 percent of human births.

His prediction may yet be on target.

In discussing the idea in his work Daedalus–a reference to the inventor in Greek mythology who, through his inventions, strived to bring humans to the level of the gods–Haldane was diving into issues of his time, namely eugenics and the first widespread debates over contraception and population control.

Whether Haldane’s view will prove correct about the specific timing of when ectogenesis might become popular, or the numbers of children born that way, it’s certain that he was correct that tAt the same time, he was right that the societal implications are sure to be significant as the age of motherless birth approaches. They will not be the same societal implications that were highlighted in Daedalus, however. 

Technology developing in increments

Where are we on the road to ectogenesis right now? To begin, progress has definitely been rapid over the last 20-30 years. In the mid 1990s, Japanese investigators succeeded in maintaining goat fetuses for weeks in a machine containing artificial amniotic fluid. At the same time, the recent decades have seen rapid advancement in neonatal intensive care that is pushing back the minimum gestational age from which human fetuses can be kept alive. Today, it is possible for a preterm fetus to survive when removed from the mother at a gestational age of slightly less than 22 weeks. That’s only a little more than halfway through the pregnancy (normally 40 weeks). And while rescuing an infant delivered at such an early point requires sophisticated, expensive equipment and care, the capability continues to increase.

A comprehensive review published by the New York Academy of Sciences three years ago highlights a series of achievements by various research groups using ex vivo (out of the body) uterus environments to support mammalian fetuses early in pregnancy. Essentially, two areas of biotechnology are developing rapidly that potentially can enable ectogenesis in humans, and, along the way, what the authors of the Academy review call partial ectogenesis.

Because a fetus develops substantially with respect to external form and internal organs during the second half of pregnancy, our current capability to deliver and maintain preterm infants actually is a kind of partial ectogenesis. Supported by all of the equipment in the neonatal intensive care unit (NICU), a premature infant continues its development as a normal fetus of the same gestational age would do inside the mother’s uterus, but with one important exception. Inside the womb, oxygenated, nourished blood comes in, and blood carrying waste goes out, through the placenta and umbilical cord. Once delivered, however, a preemie must breathe through its lungs, cleanse the blood with its liver and kidneys, and get nutrition through its gastrointestinal tract.

But because these organ systems, especially the lungs, are not really ready to do their job so early, there is a limit to how early a developing fetus can be transferred from womb to NICU. Known as viability, the limit definitely has been pushed back with special treatments given to the mother prior to delivery and, just after birth, directly into the preemie’s lungs, and with intensive support. But the 22 week gestational age may be around the absolute limit for survival for a fetus that will have to depend on lung-breathing, not to mention other organs, rather than its mother’s nourished blood.

Still, the capability to push back the limit is around the corner. One of the two developing key technologies is the artificial amniotic fluid filled environment that has continued to develop with laboratory animal models since the work with goats in the 1990s. The other area is embryo transfer. Not only can a developing mammal be transferred from the uterus of its own mother to that of a surrogate, but gradually investigators are reproducing the endometrium–the cell layer of the uterus that contains and nourishes the pregnancy–as a cell culture, or an in vitro model. The convergence of these technologies will make it possible to transfer a developing human into a system that includes the placenta and umbilical cord and supplies all consumables (oxygen and food), and removes all waste, directly through the blood.

Thus, survival and continuing development would not depend on the lungs and other organs being ready yet to do their job. Applying such a system to fetus delivered in the middle of pregnancy would constitute real partial ectogenesis. Furthermore, since bypassing the developing, not fully functional organs, stands to improve survival substantially, and might even decrease the costs of extreme premature birth, the movement of the technology from research to clinic is inevitable.

Once that happens, there will be no obstacle against pushing the limit further, toward full ectogenesis. But there will be no obstacle to pushing the limit akin to how lung viability has placed an obstacle to conventional pre-term care. At some point, an in vitro fertilized egg could be planted directly into the artificial womb, with no need for a natural uterus even for the early stages.

Societal implications

An artificial womb may sound futuristic, and in Haldane’s time this may have supported a perception that realizing the technology would go together with controlling the birth rate and eugenics controlling which humans come to life, and thus which genetic traits get passed down to future populations. But today, we could do these things without ectogenesis. We have plenty of contraceptive methods and can sterilize people, or make them more fertile, while pregnancies can be induced with implanted embryos made with in vitro fertilization.

If anyone is working on a eugenics program at present, they can use surrogate mothers and don’t really require an artificial uterus–unless, we imagine a society that routinely, forcefully sterilizes all females, so that whoever has the artificial uterus has a monopoly on reproduction, ectogenesis does not relate particularly to those 1920s issues. Instead, the artificial uterus would simply move the pregnancy outside of the woman’s body. When considering societal consequences, that’s the main factor that we need to keep in mind, and doing so we see that it does relate to many currently controversial issues.

Considering abortion, for instance, while the proposition that a fetus, even an embryo, is a person with a “right to life” is a religious belief that cannot be imposed on everyone else, the main argument for the right to choose is a woman’s right to control her body. If a developing embryo or fetus is not viable and the mother wants it out of her uterus, that’s her right.

But what happens once we have the technology to remove it from her without killing it and let the pregnancy continue in an artificial womb? Already, with NICU technology pushing back the survival limit, the timing of viability affecting the legality of abortion, has been challenged by abortion foes. The prospect of ectogenesis stands to turn the viability issue on its face, and it will be interesting to see where that leads.

While social conservatives might be receptive about what an artificial uterus might do to the abortion paradigm, make no mistake they’d probably not be happy that the technology also stands to make it much easier for male gay couples to have babies. All they’d need is an egg donor; no more need for a surrogate mother to take the embryo into her uterus and carry it for 40 weeks. That’s easier for any gay couple in terms of practicality, waiting periods, and money. The same thing goes for a transgender person wishing to have a child.

Finally, because of the sheer numbers, the artificial uterus could have major implications for heterosexual women with fully functional uteri. Many who want children of their own might prefer to forego pregnancy yet would hesitate to hire a human surrogate. Not only is it expensive, but the surrogate could grow fond of the fetus she’s carrying, so why bother taking the risk?

On the other hand, the mind set could be quite different if the surrogate were a high tech jar. It’s your baby with no worries about competing mothers. I’m not suggesting that all potential mothers would opt for this, but Haldane’s guess might not be so unrealistic in that it might end up being a substantial fraction of the population.

David Warmflash is an astrobiologist, physician and science writer. Follow @CosmicEvolution to read what he is saying on Twitter.

What Mars colonists need to bring from Earth: A large gene pool

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When futurist entrepreneur Elon Musk discusses his vision for Mars colonization, he speaks about delivering 80,000 settlers initially, and eventually millions to the Red Planet. That’s very different from most other well-publicized Mars colonization advocacy groups, like those of the Mars Society, or Mars One, whose plans are for transporting much smaller populations to the Martian surface with the idea that this will eventually stimulate a gradual increase in colonists from Earth.

Whether any of these plans come to fruition is somewhat doubtful—Mars One has been criticized as being nothing more than a reality TV show. But its overall strategy of sending just a few pioneers sounds somewhat feasible at least compared to Musk’s given the hardware and fuel requirements of sending anything (or anyone) across interplanetary space.

Sending 10 people or so certainly could serve as a proof of concept analogous to America’s Spanish and Portuguese outposts in the early 1500’s, or the English and Dutch settlements in the early 1600’s. In these instances the populations measured in the dozens and would not have amounted to a lasting European presence had they not been followed by thousands of new settlers over the next few decades. But, given our more advanced technology, our level of medicine, the idea that humans could have equipment that will utilize the Martian environment to produce food, air, and other consumables, and the certainty that settlers will not be at war with the Martian equivalent of the Aztecs or Incas—couldn’t a Martian settlement survive long term with just a low number of colonists?

The answer is no—not if the goal is a permanent human presence. Not if the goal is to provide our species with some kind of extinction insurance against planetary disaster on Earth, such as a mega-volcanic eruption, nuclear war, or some other existential threat. Mars setters can use technology to get air and food from the Mars environment, but early European explorers in the New World had access to one natural resource that mid-21st century Mars colonists will not be able to manufacture: a human gene pool.

If we really want Martian colonies, we can’t send just a few Adams and Eves. We can’t set-up a Martian Jamestown of 100 people. Long-term survival will depend on the genetic diversity of a large gene pool, and this means the Elon Musk plan of sending thousands might be the only colonization plan that could work.

Population genetics applied to Mars

A gene pool is exactly what it sounds like. It’s a collection of all the genes of a population, meaning all of the alleles—different forms of genes that children inherit from their parents. A well established principle in population genetics states that a population’s ability to survive over the long term, depends on its adaptability, which depends in the diversity of genes and alleles in the gene pool. Among humans that interbreed on Earth, there is tremendous diversity, but if we pluck out just a small sample of that population and place it on Mars, the genetic diversity of a population descending from those people will be extremely low. It’s called the founder effect, it’s thought to be the reason for the emergence of certain genetic diseases, such as Tay-Sachs and Gaucher disease in Ashkenazi Jews and Ellis–van Creveld syndrome in Amish people, and is one of the main sub-types of a genetic sampling error, called genetic drift, that acts as a force of evolution.

The only way to have no genetic drift is to have a population that’s infinitely large, but large size and high diversity can be enough to work against founder effects and another type of genetic drift called bottlenecking (instead of a small group relocating, the bulk of a population is eliminated, leading a small group).

In human history, there have been many founder and bottleneck events. They have helped to shape evolution of the gene pool of different groups of humans, but they’ve also wiped out populations.

How to keep gene pools healthy

Along with a large starting population with genetic diversity, another phenomenon from population genetics that would be beneficial to a Martian population is gene flow. This is kind of the opposite of genetic drift; it means adding new diversity to the gene pool, which in this case means new immigrants from Earth. This sounds intuitive, and certainly either in the Musk scenario, or in a more modest Mars colony plan, new settlers would be arriving generation after generation. But we’d want to avoid starting off with a low population and reproducing with that even for the first couple of generation. Most people today know that it’s bad to reproduce with one’s cousin.

To take a more extreme example, imagine a scenario like the 1970’s TV comedy, Gilligan’s Island; seven people are marooned on an island. If they never get rescued, suppose two characters—Ginger and the professor, Gilligan and Maryanne—get together and have children. After a couple of generations, everyone will be homozygous for multiple genes (have two copies of the same allele) as opposed to heterozygous (two different copies). That might lead to a surprisingly high number of redheads (if Ginger’s red hair was natural). But when it comes to recessive (need two copies of disease causing allele) diseases, decreasing the level heterozygosity in a population is also a very serious thing. With a small enough population in just a few generations, diseases would appear that were never even known before, and in studies using non-human animals with short generation times, it’s been demonstrated that low rates of heterozygosity correspond to robustness of the population as a whole. This totally dovetails with the idea that small population size and low genetic diversity put populations at risk.

Quantifying genetic needs for off-world colonies

While all of this may sound speculative, it’s not. It’s based on hard genetics that have been quantified, not specifically for Mars colonization, but for the scenario of humans settling across interstellar space. Portland State University anthropologist Cameron Smith has calculated that for the gene pool of human colony on a planet of another star to be healthy enough to enable long-term survival, a minimum of 10,000 colonists, preferably 40,000, will be needed.

To be sure, Smith’s interstellar scenario doesn’t match perfectly with a Mars colonization setting, in which continuing waves of settlement from Earth can be the norm. Still, the settlement cannot be dragged out too much. From the beginning, the gene pool will have to be large and diverse enough to make the first settlements worthwhile. Otherwise, the settlers will either be returning to Earth and it will be a false start, or the early generations will be on shaky genetic ground and will need to be replenished with new immigrants from Earth anyway. So, along with breathable air, food, our culture, ambition, and technology, human genes will be among the most valued commodity of early Martians.

These 3 Alien Planets Around a Tiny, Cold Star Just Might Support Life

David Warmflash is an astrobiologist, physician and science writer. Follow @CosmicEvolution to read what he is saying on Twitter.

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Three potentially habitable Earth-size planets have been discovered orbiting a dim, cold nearby star that is barely larger than Jupiter, researchers say.

“These kinds of tiny, cold stars may be the places we should first look for life elsewhere in the universe, because they may be the only places where we can detect life on distant Earth-sized planets with our current technology,” study lead author Michaël Gillon, an astronomer at the University of Liège in Belgium, told Space.com.

Astronomers focused on a star originally named 2MASS J23062928-0502285 that was discovered using TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope), a telescope in Chile. This dim cold red star, now known as TRAPPIST-1, is located in the constellation of Aquarius about 39 light-years from Earth. In comparison, Alpha Centauri, the nearest star system, is about 4.3 light-years from Earth. [Watch: See how the 3 TRAPPIST-1 Planets Might Support Life]
This artist’s illustration depicts an imagined view from the surface of one of the three newfound TRAPPIST-1 alien planets. The planets have sizes and temperatures similar to those of Venus and Earth, making them the best targets yet for life beyond our solar system, scientists say.
This artist’s illustration depicts an imagined view from the surface of one of the three newfound TRAPPIST-1 alien planets. The planets have sizes and temperatures similar to those of Venus and Earth, making them the best targets yet for life beyond our solar system, scientists say.
Credit: ESO/M. Kornmesser

TRAPPIST-1 is 2,000 times less bright than the sun, a bit less than half as warm as the sun, about one-twelfth the sun’s mass, and less than one-eighth the sun’s width, making it only slightly larger in diameter than Jupiter. TRAPPIST-1 is a type of star known as an ultracool dwarf that is very common in the Milky Way, making up about 15 percent of the stars near the sun.

Scientists spotted the three planets by observing TRAPPIST-1 dimming at regular intervals as the worlds crossed in front of it. This is the first time that distant planets, called exoplanets, have been found around an ultracool dwarf, the researchers said.

“So far, the existence of such ‘red worlds’ orbiting ultracool dwarf stars was purely theoretical, but now we have not just one lonely planet around such a faint red star, but a complete system of three planets,” study co-author Emmanuël Jehin, an astronomer at the University of Liège, said in a statement.

These three planets are each only about 10 percent larger in diameter than Earth. “The kind of planets we’ve found are very exciting from the perspective of searching for life in the universe beyond Earth,” study co-author Adam Burgasser at the University of California, San Diego, said in a statement.

The two innermost planets are about 60 to 90 times closer to their star than the Earth to the sun, with orbits only 1.5 and 2.4 days long, respectively. The orbit of the third planet is currently less certain, ranging between 4.5 and 73 days long. The small size of the star and its planets’ orbits means “the structure of this planetary system is much more similar in scale to the system of Jupiter’s moons than to that of the solar system,” Gillon said in the statement.

Although all three planets orbit very near their star, the inner two planets receive only four times and two times, respectively, the amount of radiation that Earth receives, since their star is much fainter than the sun. The third outer planet probably receives less radiation than Earth does, the researchers said.

Given how close TRAPPIST-1’s trio of planets are to its star, the researchers suggest TRAPPIST-1’s gravitational pull likely forced these worlds to become “tidally locked” to it. When a planet is tidally locked to its star, it will always show the same side to its star, just as the moon always shows the same face to Earth. This causes those worlds to each have one permanent dayside and one permanent nightside.

The third of TRAPPIST-1’s planets, the one farthest from the star, may lie within the star’s habitable zone — the area around a star where planets have surfaces warm enough to have liquid water, a key ingredient to life as it is known on Earth. The two planets closest to TRAPPIST-1 may have daysides that are too hot and nightsides that are too cold to host any kind of life as it is known on Earth, but the researchers suggest that the borders of the planets’ day- and nightsides may be sweet spots temperate enough for life.

For the most part, exoplanet-hunting missions have focused on finding systems around sun-like stars emitting visible light, but these stars can be so bright, they can drown out key features of their planets, the researchers said. In contrast, cold dwarf stars emit mostly infrared light, and are so faint they would not overwhelm details of their planets. TRAPPIST was designed to look for planets around 60 nearby ultracool dwarfs. [7 Ways to Discover Alien Planets]

“The detection of these planets [around TRAPPIST-1] should intensify the search for more systems around ultracool dwarfs,” Gillon said. “Exciting scientific adventures are now beginning.”
This image shows a size comparison between Earth’s sun (left) and the tiny, ultracool dwarf star TRAPPIST-1 located 40 light-years from Earth. The star is home to three alien planets that may have the potential to support life.
This image shows a size comparison between Earth’s sun (left) and the tiny, ultracool dwarf star TRAPPIST-1 located 40 light-years from Earth. The star is home to three alien planets that may have the potential to support life.
Credit: ESO

Since the planets around TRAPPIST-1 are relatively nearby, scientists can in principle analyze the compositions of their atmospheres, “and further down the road, which is within our generation, assess if they are actually inhabited,” study co-author Julien de Wit, a planetary scientist at Massachusetts Institute of Technology, said in a statement. “All of these things are achievable, and within reach now. This is a jackpot for the field.”

The masses of these worlds remain unknown, but future research can pinpoint how much each of these planets gravitationally pulls at its siblings when they get close to each other, Gillon said. The strength of each planet’s gravitational pull will help scientists deduce its mass, which in turn will help them estimate the planets’ densities and, thus, compositions, he added.

“We can tell if the planets are probably rocky, or rich in ice like the moons of Jupiter, or rich in metal like Mercury,” Gillon said.

The researchers noted that the Hubble Space Telescope and the forthcoming James Webb Space Telescope could help analyze the atmospheres of those planets for molecules linked with life, such as water, carbon dioxide and ozone.

“Now we have to investigate if they’re habitable,” de Wit said in the statement.

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