Biomimicry: Animal-Inspired Inventions

Biomimicry: scientific & engineering inventions inspired by animals

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Nature is truly fascinating but what really grabs my attention is the fact that humans can take such inspiration from it. Animals are equipped with everything they need to survive and by looking at their abilities and adaptations, we’re able to come up with inventions that also help us to thrive.

What is Biomimicry?

What is biomimicry?

Humans have long been interested in how nature can up the game in terms of technology and science. This has resulted in the study of natural organisms and the use of nature as a model in a practice known as biomimicry.

Sometimes called biomimetics, this practice involves looking at processes and designs from nature and taking inspiration from them to find solutions to human problems.

When you look around, you’ll see inventions, architecture, and materials that have been inspired by nature and these are applied to so many different things like design, science, engineering and problem-solving.

Some things that we take for granted are actually the result of biomimicry. For example, did you know that Velcro was invented after the creator got some burdock burrs stuck to his clothing on a hike?

There’s still plenty of research to be done in the field of biomimicry which will allow us to discover the resilience, durability, and efficiency of natural processes and designs.

Scientific & Engineering Inventions Inspired by Animals

As things stand, there are an estimated 8.7 million species of animals on planet Earth, and we’re always discovering new ones. As we observe these creatures, we become more and more inspired by their natural design and the processes they use to survive. Let’s take a look at some examples.

1. Spider Silk (Bulletproof Armor)

When you think of strong materials, your mind might not automatically go to spider silk. But this amazing natural material has been shown to have greater strength than even the strongest man made materials, like Kevlar. In fact, it’s said to be six times tougher!

Not only is spider silk incredibly strong in terms of its strength to weight ratio, but it’s also super lightweight and very flexible. These benefits mean that spider silk can be used to make bulletproof armor that doesn’t weigh the wearer down like traditional armor. Plus, it’s breathable and so effective that even the US Army is considering using it. It’s also worth noting that spider silk is readily able to absorb shock which makes it even more viable as a material for bulletproof armor. 

Spider silk is made up of various proteins whose structure is incredibly robust. By looking at this structure as well as the biological processes used to make it, humans are now able to replicate this and create man made spider silk with all of the same properties.

If all of that wasn’t impressive enough, imagine being able to make bulletproof vests and other armor from a completely sustainable material. Since spider silk is 100% biodegradable, we wouldn’t have to worry about waste.

2. Kingfisher (Shinkansen Train)

The kingfisher is undoubtedly one of nature’s most beautiful birds, but it’s also quite the mover thanks to its aerodynamic shape. When moving through the air, this bird’s streamlined body allows it to move at speeds of up to 25 mph (40 km/h).

We’re all familiar with the Japanese bullet train that’s known for its efficiency and speed, but did you know that the very design for this transportation method came from the humble kingfisher? Look at the front of the Shinkansen train and you’ll notice how it’s remarkably similar to the beak of the kingfisher.

Not only does this improve the speed and ease of movement of the train, but it also decreases the sonic boom as it enters a tunnel. This reflects how the kingfisher’s shape allows it to smoothly enter water at speed.

For those on board, this smooth design makes for a much more comfortable ride in terms of noise and vibrations. What’s more, having a streamlined design results in a more stable structure for trains that move at such high speeds of up to 200 mph (322 km/h)!

On top of all this, scientists have noticed how the kingfisher is easily able to dive into the water using as little energy as possible. By drawing inspiration from its shape, designers were able to create a bullet train that was just as efficient and required far less energy than you might imagine. In fact, it’s reported that the bullet train uses up to 88% less energy than a commercial airliner and produces 92% less carbon!

3. Beaver (Better Insulating Wetsuits)

A wetsuit will keep you dry, but it doesn’t always keep you warm and that’s a big problem for people that like to spend a lot of time in the water, like surfers.

You’ll notice that beavers spend a lot of time in the water but their fur is perfectly designed for this. Not only is it covered in a water-repellent oil, but it’s also able to trap warm air to keep the animal at the right temperature. Their fur is incredibly dense, and these characteristics have been mimicked by scientists who have managed to create a wetsuit that could also keep you warm.

The thermal efficiency of beaver fur has been replicated in the form of a rubber-lined suit with hairs that mimic those found in beaver pelt. Scientists have figured out just the right density and hair length for optimal warmth.

While this might sound like a bulky solution, there is hope. The beaver-inspired wetsuit has been designed to be easy to wear and incredibly flexible, so your range of movement in the water won’t be hindered. Plus, it’s super lightweight and boasts impressive durability along with the same buoyancy we see in beaver fur, so it’ll likely make being in the water much safer as well.

4. Mosquito (Painless Hypodermic Needles)

I hate needles, and while it’s not necessarily the pain that bothers me, getting rid of it would certainly help. If you’ve ever been bitten by a mozzie, you’ll probably not have noticed until after the fact when your skin starts itching and turning red. That’s because the mouthparts of the mosquito are just like little hypodermic needles that deliver no pain when they bite.

This innovative natural design is something that humans have been able to draw inspiration from and scientists are looking at ways to produce needles that don’t come with that sharp prick. This is partially thanks to the microscopic serrations along the edge of the needle, just like those seen on the mozzie’s proboscis. What’s more, when we observe the mosquito feeding, we see that it has the special ability to move its mouthparts to locate blood; this pivoting mechanism can also be used for medical specialists to target a certain spot when administering vaccinations or drugs and even when taking blood.

Even more interesting is that scientists are able to replicate the nanostructure of the mosquito proboscis which is ideal for more technological applications.

While a mosquito bite may cause localized pain, it does minimal damage to the tissue and that’s something that humans can really draw on. For people like me that cringe at the thought of a needle, this less painful process is certainly a welcome one.

5. Humpback Whales’ Flippers (Wind Turbine Blade Design)

The humpback whale is an awe-inspiring animal at the best of times, but it becomes even more fascinating when you consider that its flippers have inspired the design of wind turbine blades.

Humans are always looking for ways to harness energy in an efficient and eco-friendly manner, and the whale’s flippers might just hold the key. Consider how their very shape is designed to maximum lift and maneuverability while the animal is in the water, and then think about how this same shape could increase the efficiency of the turbine blades, harvesting as much energy as possible. 

What’s more, for an animal with such a large size (up to 49 feet (15 meters)) these gentle giants move almost silently through the ocean. That’s again thanks to the shape of their flippers which can be used when creating wind turbines that produce very little noise pollution. 

When the wind turbine is in operation, stiff blades would decrease its efficiency. But by looking at the flexible natural design of the humpback’s flippers, we can again come up with a shape and material that is as flexible as possible.

If you look at the whale’s flippers, you’ll notice bumps along the front edge; these are called tubercles, and they help to improve the aerodynamics of the flipper. Applied to wind turbine blades, these tubercles ensure more lift and less drag while also contributing to decreased turbulence. Where harvesting wind is concerned, this is essential to keep airflow consistent. 

This technology has been researched for more than a decade and while wind turbine blades are the main point of focus, it can also be used for other applications, including propellers and boat rudders. 

6. Sharks (Antibacterial Surfaces)

Sharks might be considered as the villains of the sea, but they’re actually very inspirational, especially when it comes to their skin. That’s right, shark skin has a unique microstructure that’s perfect for repelling bacteria and stopping it from sticking to the surface. The skin is covered in small tooth-like structures known as dermal denticles (literally skin teeth) and these have caught the attention of human innovators. 

Off the back of this inspiration, a material known as Sharklet has been created which aims to replicate the antibacterial properties of shark skin. With tiny structures arranged in a diamond pattern, this is one of the first nature-inspired, bacteria-repelling materials on the planet.

The applications for Sharklet could be endless but at the moment, there’s a heavy focus on its use in a medical setting where the proper management of bacteria and cross contamination prevention is essential. What’s more, the material could be used to create ‘self-cleaning’ surfaces that reduce the need for chemical cleaners, resulting in an eco-friendlier solution. Eventually, there’s hope that this concept could be applied to all different kinds of materials.

7. Termite Mound (Self-Cooling Building)

Termites are among some of the most impressive architects in nature, but their nests aren’t only amazing to look at; they could be a solution for sustainable human architecture.

Termites live in hot climates in tropical and subtropical parts of the world, so good ventilation within the nest is essential to their survival. Regardless of the external temperature, termites build a nest that regulates its own internal temperature, keeping it cool and comfortable. This is thanks to the network of tunnels and vents that are perfectly placed around the nest for optimal airflow.

Up until now, humans have relied on cooling systems that use a lot of energy and aren’t good for the environment. But by taking inspiration from termite nests, there’s hope for architecture that could manage its own temperature. Examples of this have already been constructed, such as the Eastgate Center in Zimbabwe.

Not only does the unique structure of the termite mound promote temperature control, but it also ensures humidity regulation. This is another feature that architects have been looking at to further ensure the comfort of these biomimetic buildings. If that wasn’t enough, scientists have x-rayed termite mounds and found that they’re even designed to be self-draining. Could this be another feature implemented by humans in the future? Time will tell. 

8. Blue Morpho Butterfly (Anti-Counterfeiting Technology)

The blue morpho butterfly is one of the most stunning butterflies in nature with its iridescent wings that are able to diffract light being made up of microscopic scales. When this light is diffracted, this is what gives the butterfly its stunning coloration but it doesn’t just look good; this wing design has inspired some innovative anti-counterfeiting technology.

Since each butterfly wing’s nanostructure is totally unique, it would be very difficult to replicate, and scientists have used this concept to design patterns that would also be hard to copy which is essential in applications such as passports, ID documentation, and high value product packaging. Moreover, by implementing the same techniques, we’re able to come up with tools for forensic identification.

What’s more interesting is that when you look at a blue morpho butterfly from different angles, its coloration changes according to how the light falls on it. When used for human purposes, this concept makes any given pattern even more of a challenge to recreate. Plus, each pattern can be customized with its own unique features.

Since the design and pattern of each nanostructure is so difficult to replicate, this adds an additional layer of authenticity and security to the application it is applied to.

9. Gecko Feet (Adhesive Tape)

Have you ever seen a gecko clinging onto a surface seemingly defying gravity? Then you’ve seen one of nature’s most amazing magic tricks. These lizards have a natural ability to adhere to surfaces thanks to a phenomenon known as van der Waals force. This is, in the simplest terms, the interaction between atoms and molecules. However, while it does allow the gecko to stick to surfaces using its feet, this type of adhesion is comparatively weak and easy to disturb.

With the gecko, if you were to look under a microscope, you’d see that there are tiny hairs over the surface of the foot which increase its surface area and therefore makes van der Waals interactions more possible.

Scientists have used this idea to create adhesive tape that also draws inspiration from the fact that gecko adhesion is dry and doesn’t leave behind any residue. For this reason, it is reusable as nothing is lost during the adhesion process. Therefore, adhesive tape, such as Setex, that is inspired by gecko feet is indeed reusable which is an eco-friendlier option. 

Typically, when we use adhesive tape, there are limitations in terms of which environments it’ll be effective on. However, since gecko-inspired tape takes the notion of being adaptable, it’s easier to use regardless of factors like humidity. Moreover, geckos are able to stick to surfaces at various angles, which has inspired innovators to produce tapes that mimic this trait. As a result, we’re seeing adhesives that are very useful in robotics as well as in medical settings which benefit from the lack of residue.

10. Chameleon (Camouflage Technology)

We all know the amazing ability of the chameleon which changes color according to its surroundings. It does this primarily for communication with other chameleons and potential predators, and it’s all because of cells called chromatophores whose pigmented cells can quickly change color. This happens in response to various stimuli, including temperature, the environment, and even the chameleon’s mood.

So where does this come in with biomimetics? Well, there’s quite a lot we can do with chameleon inspired technology and scientists are looking at ways of producing responsive camouflage materials which could be used in a number of applications. They’ve even developed a robot that benefits from the ability to collect information from its surroundings and change its artificial skin accordingly.

Once this technology is fully developed, the aim is to create materials that are responsive and seamless enough to perfectly blend in with their surroundings, drawing inspiration from the chromatophores of chameleons. The aspiration is that someday, this technology could be utilized for concealment in military applications.

As well as being able to change color, the chameleon is also able to control the infrared reflectivity of its skin. This is something else that’s inspired innovators and could also go a long way in a military setting for greater stealth and concealment. Studies have been looking at replicating this using thermal liquids and nanowire heaters which react to environmental changes.

11. Honey Bees (Swarm Robotics)

The honey bee is a creature that has long fascinated me because of its extreme intelligence, especially when it comes to hive communication. These amazing insects have communication systems that allow entire colonies to make collective decisions for the greater good. When a colony gets too large, for example, the bees just ‘know’ that they need to swarm with tens of thousands of individuals working together to move and find a new place to call home.

What’s more, within the hive, the bees work together to locate resources, and each member of the colony is assigned his or her own task. Even when it comes to finding food, these bees will use what’s known as the waggle dance to indicate the direction and quality of a food source. 

With this amazing natural inspiration, scientists have been looking at how swarms of robots might operate in a similar fashion to the honey bee. This might include the ability to communicate with one another to achieve a common goal, with each robot having its own job. For example, in search and rescue or for locating resources.

Another great way that this technology could be used is in the field of autonomous robotic systems for things like weather surveillance. The collective intelligence of the robots would mean that decisions could be made that benefit the system as a whole, without any human interference. What’s more, it’s thought that this could be achieved without a central ‘brain’ but rather each robot being able to communicate with its peers locally. Some of this has been inspired by the waggle dance I talked about earlier.

Honey bee colonies are so successful because they work together. There’s hardly any risk that the failure of an individual would result in the demise of the colony. When applied to biomimicry, this means that we could create groups of robots that have their own allocated tasks but that also work together for greater success. Moreover, just like honey bees, these robots would be able to allocate a suitable number of individuals to any given task depending on the need.

12. Fireflies (LED Technology)

Fireflies are nature’s very own little lights and they exhibit this ability to produce their own light through a process called bioluminescence which involves a biological chemical reaction. They use this for communication and have various pulsating patterns depending on what they’re trying to communicate. In some cases, individuals will synchronize their patterns and this is something that could be used in entertainment using LED lights. 

But that’s just the tip of the iceberg. This amazing natural phenomenon has inspired scientists to develop affordable, energy efficient LED lights that create very little heat. Not only are these lights more sustainable and efficient but far more long lasting than their traditional counterparts.

Many homes and businesses now use LED lighting for its longevity and eco-friendly design but most people don’t know that it was inspired by the humble firefly. What’s more, have you ever noticed how LED lights aren’t overly bright? That’s another thing that was inspired by the firefly but doesn’t impact the useability of the light. In fact, going even deeper, biomimetics has allowed us to look at fireflies to choose the optimal wavelength for lights. One great example of this is the design of ‘sleep lights’ whose color helps you to get a good night’s rest. Some LEDs also have a stronger wavelength that helps to replicate daylight and improve focus in the workplace.

But what’s really exciting is the adaptability of LED lights and this is again inspired by nature because fireflies have the built-in ability to change the intensity of their light depending on their surroundings. This has inspired the creation of LED bulbs that adjust throughout the day and help us to stay in our circadian rhythm.

13. Elephant’s Trunk (Robotics & Prosthetics)

Of all things in nature, the elephant trunk is perhaps one of the most versatile appendages. These animals use their trunks for everything from lifting heavy objects to delicate tasks, for sensing things, and even for communication.

They have what is known as a prehensile trunk, which essentially means that it acts like an extra limb and allows the elephant to grasp things and pick up items. When this same concept is applied to science, it’s obvious that it is the perfect inspiration for prosthetics.

Imagine a prosthetic limb that was capable of a greater range of movement, the ability to grasp items more securely, and that had much greater strength. All of these things may be possible by modeling said prosthetic on the elephant’s trunk. But what’s most exciting is the potential to look at the sensory receptors in the trunk and mimic this in prosthetics for artificial limbs that are able to respond to external stimuli in real time!

There’s even discussion about a biohybrid system whereby prosthetics are combined with biological tissue for a more seamless and natural performance.

But interestingly, this concept doesn’t only apply to prosthetics. The same inspiration could be applied to soft robotics to create robots that are capable of performing delicate tasks, lifting heavy objects, and that boast a greater degree of flexibility.

14. Hagfish Slime (Strong Flexible Fibers)

Hagfish use cells called skeins to produce a thick slime that fills the mouth and gills of their attacker.

The poor old hagfish has got a reputation as being one of the ugliest fish on the planet and to be  honest, its slime is pretty gross too. But as they say, never judge a book by its cover because that slime has been a source of inspiration as far as biomimicry is concerned.

The hagfish produces its slime when attacked by a predator and for a gooey mass, it’s surprisingly strong. That’s thanks to thread-like fibers that scientists have drawn inspiration from to create super strong high tensile materials. In studies, this slime was almost as strong as spider silk!

What’s more, these materials are incredibly flexible, so could be used for an array of applications like medical equipment and implants, textiles, and manufacturing. But one of the most exciting ways we could use this is for protective gear which would boast amazing strength but still be comfortable to wear owing to its flexibility.

Even more interesting is that the slime of the hagfish is actually self-cleaning insofar as particles and debris are unable to stick to it. However, this could be applied to the creation of materials that would be able to resist dirt.

With all of these properties, hagfish slime inspired materials are certainly worth getting excited about. Plus, since these materials would be biodegradable, they’d meet the growing demand for more sustainable products.

15. Mantis Shrimp (Lightweight Impact-Resistant Materials)

The mantis shrimp might look like a beautifully ornate creature but underneath that colorful exterior lies a hardened warrior. These shrimp possess a dactyl club, which they use to whack anything that gets in their way; whether it be predator or prey; or even each other. These clubs have a calcified impact area which is resistant to breakage but are also covered in a more flexible material for a greater range of movement.

What’s more, when we look at how the club is able to dissipate kinetic energy, we see that the shrimp can withstand a significant impact without absorbing shock and damaging the rest of its body.

So, when it comes to biomimetics, the mantis shrimp has played a crucial role in the development of materials that can resist impact, even at speed, but remain lightweight and flexible. Look at how the dactyl club is formed with layers of fibers that won’t move sideways during impact, causing them to never crack. If we can apply this to areas such as sports, protective gear, and even in the production of vehicles, imagine the durability and resilience of these products.

What’s more, by following the natural design of the mantis shrimp’s club, inventors will be able to create products without using excessive materials, which goes a long way to the sustainable future we’re all aiming for.

16. Woodpeckers (Head Protection)

If you consider that a woodpecker pecks at more than 20 times per second, you’d imagine that they might do some serious damage to their heads in the process. But they don’t! That’s because of their perfect design which allows them to hammer at trees all day without so much as a mild headache.

Inside the skull of the woodpecker we find the hyoid bone. In humans, this is a pretty simple structure but in woodpeckers, it’s responsible for absorbing more than 97% of the shock from pecking at trees. Couple this with lots of spongy cartilage and you’ve got a skull that’s as good as a helmet. Although, studies have shown that rather than being like a helmet, the woodpecker’s skull is more like a stiff hammer!

And that’s where humans are taking their inspiration; creating headgear that’s just as resistant to impact. By looking at how the hyoid bone and cartilage work to absorb shock, we’re able to create protective gear with similar properties. For example, consider something like sports equipment designed to protect from shock. Since the woodpecker has a tongue and beak that increases the surface area of the impact, scientists could find ways to replicate this in protective equipment for sports, better distributing force and reducing the risk of injury.

In addition to this, these structures help to minimize vibrations and could pave the way to gear that drastically reduces the risk of brain injury or concussion.

17. Polar Bear (Heat Insulation)

Life in the Arctic Circle can get pretty chilly, so animals there have adapted ways of staying warm and the polar bear is a great example of this. These animals have incredibly dense fur, but the individual hairs are hollow which improves insulation by trapping warm air. This is also what makes the polar bear appear white as the sun reflects off those hollow hairs. Interestingly, this is another way to conserve warmth, as the dark skin absorbs heat from the sun.

During the colder months, polar bears’ coats become much denser, but they’ll shed somewhat during summer, proving just how adaptable they are. Moreover, when the polar bear gets into the icy water, the hydrophobic properties of its fur prevent water from being absorbed and making the animal colder. They’re also incredibly buoyant which, when coupled with the water-repelling nature of their fur, serves as excellent inspiration for insulating materials that could be used in water-based activities.

And that’s really where this inspiration takes us; insulation. We’re able to take the natural idea of hollow fibers from the polar bear and use this to create materials that better retain heat. On top of this, biomimetic researchers have taken other traits of polar bear fur, such as its reflective properties, which could also be applied to man-made materials that control solar radiation. Researchers in China have created a synthetic material that perfectly replicates the hair structure of the polar bear and are hoping for it to be used in applications such as aerospace and architecture. 

These materials also incorporate the idea of using transparent fibers which are better able to absorb heat, just like the fur of these enormous bears. Textiles may also be created that benefit from the adaptability of polar bear fur, allowing us to come up with materials that can be used in various environments and temperatures, all while remaining incredibly lightweight and comfortable to wear.

18. Springtails (Waterproof & Breathable Clothes)

The springtail is a small invertebrate, and while there are more than 7000 species, most are no bigger than a pinhead. One of their unique traits is that they breathe through their skin, so it’s imperative that it doesn’t get wet. How do they do this? Well, their skin is made up of tiny microstructures that have hydrophobic properties, enabling them to repel water.

Within the microstructures of the springtail, tiny pockets of air are created and what’s more, the structure is also able to repel dirt, meaning it’s considered to be self-cleaning

Amazingly, the springtail spends a lot of time in the water, so this is an essential trait to have. But when we look at this, it’s easy to find inspiration for materials that could benefit from similar microstructures and have their own water-repelling properties.

In addition to this, inventors are able to look at the way that springtails create those pockets of air and repel dirt, allowing them to design materials that are both breathable and easy to keep clean.

By replicating the microstructure of the springtail, we’re also able to create waterproof materials that are lightweight making them more comfortable for the user and encourage a greater range of movement. Plus, since springtails have adapted to live in a variety of conditions, this has inspired biomimetic researchers to further their creations to be adaptable and suitable for a range of applications, particularly outdoor gear that’s breathable, lightweight, water resistant, and versatile.

And if that wasn’t enough, consider that materials are being created that not only look good but are also much easier to recycle than their traditional counterparts.

19. Namib Desert Beetle (Fog Harvester)

The Namib desert beetles possess the unique ability to both repel and attract water, owing to the surface of their shell, which exhibits both hydrophilic and hydrophobic properties.

Water scarcity is one of the biggest problems in the world and sadly, more than 3.5 million people lose their lives each year because of it. In arid parts of the world, water isn’t always easy to come across, but the Namib desert beetle could be the solution. 

These amazing creatures have the ability to both repel and attract water, and it’s all because of the surface of their shell which has both hydrophilic and hydrophobic properties. When fog comes down into the air, small bumps on the shell attract water, and then hydrophobic grooves direct that water to the mouth of the beetle so it won’t become dehydrated even in arid environments. They’re even known to bask in the fog to collect water. 

By using this as inspiration, biomimicry specialists are able to create a system that effectively harvests water from thin air (known as fog harvesting) which could provide a clean water supply for people living in water scarce parts of the world. Not only this but it could be an excellent addition to agriculture settings in these parts of the world to ensure successful crop growth.

These systems not only attract water from the environment but are also equipped with channels that direct harvested water to a storage point. Of course, one of the main challenges for scientists is to adequately replicate the surface of the beetle’s shell for maximum water collection and efficiency. But initial trials have shown promising success.

As you likely know, fog is more common at the beginning and end of the day and this is when the Namib desert beetle is most active. For this reason, it would be wise for researchers to develop this technology to work along the same timelines. As such, they’re looking at solar powered systems for the most efficient operation. Combine this with the natural methods of harvesting water, and we end up with something completely sustainable.

20. Seashells (Materials Science)

There are thought to be more than 85,000 species of mollusks in our oceans, and they form their shells by absorbing sea water and salt which then develops into layers of calcium carbonate. This is an incredibly durable natural material and has been the source of inspiration for material scientists looking to create strong and resilient materials. 

When this calcium carbonate is formed, it may be arranged in many different patterns, but the shell is usually built from the mantle up. In any case, these patterns contribute to the strength of the shell, and by replicating this, we are able to come up with materials that showcase extraordinary strength. This may be useful when creating building materials, like concrete, as well as in the creation of ceramics that are far less prone to cracking and breaking thanks to their unique microstructures. Scientists have even developed a material using polystyrene cups and chalk which was inspired by seashells and could even be used in human bone replacements!

Through the use of 3D printing, they’re able to experiment with a whole range of different micropatterns to determine which are the most resilient.

But despite being incredibly robust, sea shells remain beautifully lightweight, and that’s something else that researchers are looking at when crafting these new bio-inspired materials. This means that we could create materials for use in the aerospace and automotive industries that are super hard wearing without adding any extra weight to the end product.

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