More Good Science from Nature
The natural world contains endless examples of intelligent design that can inspire scientists with wonder and inspiration.
Biomimetics: The chemical tricks of our blood (Science Daily). Yesterday’s article mentioned quantum mechanics in biology. Research at the Vienna Institute of Technology is seeking to understand something very small, too: how the hemoglobin molecule works in our blood, and how chlorophyll works in plants. Tiny vibrations in these molecules are essential to their function.
The job of hemoglobin in our body seems to be quite simple: It transports oxygen molecules through our bloodstream. But this only works so well because the hemoglobin molecule is extremely complex. The same applies to chlorophyll, which converts sunlight into energy for plants….
Not only does this help to understand biological processes, it also opens up new possibilities for using the tricks of nature in the laboratory for other purposes – a strategy called “biomimetics” that is becoming increasingly important all around the world.
Inspired by earthworms, new breathing material lubricates itself when needed (Phys.org). It looks like “gummy worms” candy, and it can’t reproduce itself, but scientists at the Leibniz Institute for New Materials are proud of their material that mimics one trick of the lowly earthworm: it can keep itself moist in a dirty environment. Some progress, at least:
The surface structure of the new material also plays an important role: “Again, we were inspired by the earthworm. Its skin surface is not smooth, but rough. That’s what we took into account in our material and roughened the surface,” explains Cui. Precisely because of this roughness, a uniform lubricating film can form and adhere well. It depends on how friction-reducing the new material can behave. “The surface structure is also important for the longevity of the lubricating effect: “We compared the sliding film on our “earthworm structures” with a sliding film on a smooth surface: our structures survive 10,000 cycles of friction, whereas sliding films on smooth structures have only 300 friction cycles,” says the chemist Cui. It is precisely this combination of rough surface and the lubricant droplets inside that is special about the new material.
Moving skin beyond the biological (Nature). Imitating the tender touch of the human hand is a big challenge for robot designers. Accident victims who have lost a limb miss that sensitive touch when outfitted with prosthetic devices. ‘Skin-like electronics that stretch and sense will create a way to monitor vital signals and build prosthetics with a sense of touch,” this article says. Katherine Bourzak writes eloquently in a way to arouse awe,
Human skin is a sensitive, sophisticated and robust organ. It is water-resistant and heals when cut. Its multitude of mechanoreceptors detect sensations such as vibration, pressure and texture — they’re sensitive enough to detect the faint pressure of a breeze or alighting flies. The tight coupling of skin sensors with the peripheral nervous system is responsible for our reflexes and allows us to pick up objects of different weights, shapes and textures without conscious thought. Such properties might seem unremarkable, but for a person with an inert prosthetic hand or an electrical engineer trying to make resilient, low-power devices, human skin is a wonder.
A water treatment breakthrough, inspired by a sea creature (Science Daily). A sea anemone is inspiring Yale scientists to design water treatment devices that mimic the creature’s ability to snare particles and ingest them into its mouth.
Actinia is a sea anemone with a spherical body that has tentacles that retract while resting and extend while catching its prey. With this marine predator as their model, the researchers synthesized the coagulant, using organic and inorganic components to replicate the structure of Actinia.
Similar to Actinia, the nanocoagulant has a core-shell structure that turns inside-out in water. The shell destabilizes and enmeshes larger suspended particles, while the exposed core captures the smaller, dissolved ones. It removes a broad spectrum of contaminants, from trace micropollutants to larger particles — many of which elude conventional methods and pose significant public health concerns.
Speaking of sea anemones, Georgia Tech biomimetics engineers are studying how clownfish avoid the poison darts in the anemone tentacles. Science Daily says that they think the two organisms exchange microbiota on their surfaces, but they’re not sure. The researchers were impressed with how clever the clownfish are. They named one escape artist Houdini.
Molecular motors: Chemical carousel rotates in the cold (Science Daily). Researchers at Ludwig-Maximilian University of Munich have devised a molecular motor that can spin in response to light. Wow. “The researchers are confident that their motor’s novel driving mechanism and unique behavior will make it possible in the not too distant future for researchers to synthesize molecular machines which, thanks to their relative insensitivity to the precise environmental temperature, will enable unique applications not possible with hitherto known motors.” They have a long way to go to match the kinds of tricks that cells do every day.
Building better batteries by borrowing from biology (Phys.org). Cell channels, that can let some molecules pass but block others, are inspiring researchers at Osaka University to imitate the feat. To increase the performance of batteries, they had to figure out how to let potassium atoms pass, but block smaller molecules.
To solve this problem, the researchers used the same mechanism your cells employ to allow the large potassium ions to pass through their membranes while simultaneously keeping out smaller particles. Living systems achieve this seemingly impossible feat by considering not just the ion themselves, but also the surrounding water molecules, called the “hydration layer,” that are attracted to the ion’s positive charge. In fact, the smaller the ion, the larger and more tightly bound its associated hydration layer will be. Specialized potassium channels in cell membranes are just the right size to allow hydrated potassium ions to pass through, but block the large hydration layers of smaller ions.
Insight into swimming fish could lead to robotics advances (Johns Hopkins University). This article begins with a video clip of a fish in a tank of moving water. “The constant movement of fish that seems random is actually precisely deployed to provide them at any moment with the best sensory feedback they need any to navigate the world,” researchers at Johns Hopkins found. It’s called active sensing, and robots with that would be better swimmers. Fish can even do it in the dark with just their electrosensing equipment. “Sensors are rarely a key part of robot design now, but these findings made Cowan realize they perhaps should be.”
Continuing from yesterday’s entry, we see a few more examples that are mere drops in the bucket of hundreds of examples of inspiring designs in life. In the years we have been reporting on biomimetics, almost every organism has provided inspiration, whether plant or animal, whether microbe or large multicellular giant, from tiny proteins to super-size dinosaurs and elephants. Let’s keep this kind of design-friendly science going. Our lives will improve, and the Darwin dogmatists will slither away back into the caves where the blind can lead their blind.