What will extraterrestrial life look like

The author said the inspiration behind the aliens comes from the mystery of the emergence of life on Earth and all the unknown organisms living among us. Just like VanderMeer, scientists look at the start of life on Earth as one big mystery and focus on discovering what ecosystems in our early years might have prompted it.

Listen to Are We There Yet? Research suggests eukaryotes developed as a result of one primitive cell — called a prokaryote, like a bacterium — absorbing another, two billion years ago. Mitochondria and chloroplasts are descendants of independent prokaryotes that entered symbiotic relationships with larger cells. The advent of eukaryotes on Earth was a vanishingly unlikely development. Together with the late Fred Hoyle, mathematician, astronomer and astrobiologist Wickramasinghe developed the astrobiological theory known as panspermia, which holds life on Earth was catalysed arrived as microbes travelling through space on meteors and interstellar dust.

He suggests that microbial life may have landed during the Hadean period, four billion years ago, when lots of smallish meteorites smacked into the planet. In a paper published in August , he suggests ET might also have been deposited on the moon. Given that all life on Earth arose from a single common ancestor, we have no way of knowing what aspects of it are law-like — found in all life, across the universe — and which are specific only to our own biosphere. It follows that life elsewhere need not involve Earth-like biology or chemistry.

On the website for the department of zoology of the University of Cambridge, the page for Arik Kershenbaum lists his three main areas of research, one of which stands out from the others. Topping the list: They evolved. He argues that evolution is a universal law of nature, like gravity — and that studies of plants and animals here can therefore tell us something useful about potential inhabitants of worlds far beyond Earth.

He finds evidence for this in the process of evolutionary convergence, in which unrelated lineages of organisms evolve similar features as adaptations to similar environmental challenges. Quanta recently spoke with Kershenbaum at his home in Cambridge via videoconference.

The interview has been condensed and edited for clarity. And because evolution is the explanatory mechanism for life everywhere, then the principles that we uncover on Earth should be applicable in the rest of the universe. Thinking about how life on other planets evolves and behaves is just a natural extension of my work with animals on Earth. No planet will have a complex form of life that popped into existence all on its own. Whatever life is like on an alien planet, it must have begun simply.

Probable, even, on many planets. If you observe two animals with similar features — feathers, for instance — you might presume that they inherited them from a common ancestor: the feathered dinosaur that was the ancestor of all modern birds. For instance, the wings of birds work in pretty much the same way as the wings of bats. But the common ancestor of birds and bats was a small lizardlike creature that lived over million years ago, long before even the dinosaurs.

So those wings must have evolved separately in different lines of descendants. And yet living a life similar to that of modern coyotes or jackals meant that it evolved many similar characteristics convergently.

The laws of physics and biomechanics constrain the ways that animals can conceivably evolve mobility on this planet. You can jump. The only other way is aerodynamically, with a wing, to generate lift. Those are the mechanics of moving through a fluid medium. On Earth, flight evolved four different times in four different groups: in birds and bats and pterosaurs and insects. And so we can expect these constraints to be operating everywhere in the universe.

Yes, bat wings and bee wings are different, but only in detail, not in principle. Both consist of a membrane supported by rigid structures. Both generate lift by creating airflow over that membrane. The small size of insects means that they cannot simply flap their wings like bats and expect to fly. They need to buzz, generating lift both on the forward stroke of their wings and on the backward stroke — something that neither birds nor bats do.

So rather than the diversity of implementations on our planet confounding our comparisons, we can actually be more confident about our predictions, because we can see how tightly constrained these solutions really are. Kronprins Haakon , betrays the landlocked illusion. Every 10 minutes or so, he plops a different hat on his head, rotating through haberdashery that includes a faux sealskin ushanka, a woven orange fez, and a beanie from the Woods Hole Oceanographic Institution , where he works.

This elusive zone is called the Aurora hydrothermal vent field. Exploring the deep sea, like venturing into deep space, is a high-risk endeavor. The abyssal seafloor is an unforgiving place for even the hardiest robots, and this mission has seen its share of mishaps, including a few heart-stopping days when it seemed like the team had lost its main underwater rover to the freezing polar ocean.

Beamed onto screens throughout the ship, the footage revealed an angry black plume erupting from a crater measuring nearly five feet across—an astonishing span for this flavor of undersea smoker. Later that night, the same camera would fly over the site twice more; and multiple passes over the next week would reveal wildly rugged terrain populating the southern slope of the Aurora seamount.

The images revealed that the vent field is covered with extinct chimneys, heaps of extruded minerals, and not just one, but at least three black smokers. The results offer our best look yet at such an exotic, ice-shrouded ecosystem. For now, Aurora is one of the closest Earth-analogs to the seafloor vents that are thought to be erupting on faraway ocean worlds, including the ice-encrusted moons Europa and Enceladus , which are considered among the best places to look for existing extraterrestrials.

Find out more with our interactive atlas of moons. The continual extrusion of mineral-rich, superheated seawater provides the heat and energy needed for some organisms to thrive in these cold, dark depths, including a menagerie of vent-specific gigantic tube worms , foot-long clams , blind shrimp , and extreme microbes.

Over the years, though, German and his colleagues have found vents populating a variety of ridges, including some that languidly go their separate ways. Our most recent target, the Gakkel Ridge , is a volcanic rift bisecting the Arctic Ocean that is spreading at the stultifying rate of less than half an inch a year. Scientists first went prospecting for hydrothermal plumes along the Gakkel Ridge in During that cruise, a layer of murky water detected near the seafloor hinted at vent activity, and a rock-dredge pulled up the remains of an extinct chimney.

Both observations could be explained by black smokers, the sort of vents that launch towers of dark, hot plumes into the water. During a second cruise in , German and his colleagues returned to Aurora aboard the icebreaker Polarstern. They searched for vents by looking for hydrothermal signatures in the water column and, toward the end of the cruise, they dropped a high-resolution camera into the deep.

Just two hours before it was time to head home, the team caught their first glimpse of a small chimney, a fleeting photobomb by a smoking vent that slid into the margins of several frames. But the vent signatures written into the freezing sea suggested that something much more massive must lie below.

How extensive is the entire system? What kind of chemistry is involved? Can the vent support a deep-sea ecosystem, and if so, what kinds of organisms live there?