Zebras: It’s in the Stripes

Ever wonder why zebras have that characteristic black-and-white pattern?

A combined research team representing universities in both Hungary and Sweden was interested in this very question. In a March 2012 paper in the Journal of Experimental Biology, the researchers published the results of their findings. Turns out, zebras don’t like being bitten by horseflies (who does, really?) The pattern on zebras (the alternating black and white stripes) creates a multi-directional array of polarized light, decreasing the attractiveness to horseflies, which prefer linear polarized light. In fact, the width of stripes falls within a special range that makes zebras most disruptive to horseflies. Since zebras live in Africa, where these flies are everywhere, this adaptation is quite helpful. A horsefly bite can have severe effects on reproductive health.

It should be mentioned that another strong hypothesis for stripes on a zebra has to do with the power of the herd. With so many striped zebras standing or running together, it is difficult for a predator to pick out just one individual to target for a meal. A lion can’t tell where one zebra ends and the other begins. Often times, one adaptation serves as a solution to multiple problems. This could very well be the case here with the zebra – both predator and parasite protection.

Bioinspiration, or biomimicry, is the methodology in which biological systems, processes, or elements are studied to draw analogies to be applied to human design challenges in a sustainable manner. Think about the human population of Africa: people are subject to the pesky biting horseflies, too. Wearing clothing patterned in a similar fashion as the zebra, or outfitting a home exterior with zebra stripes, could help keep them horsefly-free.

Applications of this innovation extend beyond humans, too. In this year’s design competition for San Diego middle school students, Emily Canizalez from Challenger Middle School invented a zebra-inspired, pest-deterring blanket for dogs. Animal print is not just fashionable—it’s also functional. But please, keep it faux!

Dena Emmerson is a biomimicry research assistant at the San Diego Zoo. Read her previous post, Cockroach Improves Search and Rescue Robots.


Cockroach Improves Search-and-Rescue Robots

Hissing cockroach

Of all the species found in nature that are inspiring new engineering designs, one would not immediately think of the cockroach as a particularly inspiring animal. But time and time again, especially in the San Francisco Bay area, the cockroach has proven to be a wellspring of information for both biologists and engineers.

The methodology in which biological systems, processes, and elements are studied to draw analogies to be applied to human design challenges is called bioinspiration or biomimicry. The University of California, Berkeley, is leading this interdisciplinary method of design with the departments of integrative biology and engineering teaming up to develop a long list of bioinspired robots. The cockroach, a pest from most perspectives, is their star organism, inspiring generations of wall-climbing, terrain-tackling, and rapid-running robots.

The latest form to come out of their program is a swinging bot. If you’ve ever seen cockroaches scatter when a light is switched on, you know they have pretty impressive evasion tactics. Robert Full, Ron Fearing, and their students discovered an even trickier tactic than scattering: disappearing completely. Cockroaches, geckos, and now robots are capable of inverting from the top of a ledge to the bottom in the blink of an eye. To accomplish this disappearing act, the robot builds up speed, and then runs right off the end of the ledge. Before completely flying off the surface, it grabs the ledge with a hind leg and swings like a pendulum 180 degrees to attach itself to the underside of the same ledge. Cockroaches not only invert themselves on a ledge, but they continue to run on the underside, retaining 75 percent of their running energy.

DASH (Dynamic Autonomous Sprawled Hexapod), the cockroach-inspired robot, is paving the way toward more agile robots, improving search-and-rescue capabilities.

Source: http://newscenter.berkeley.edu/2012/06/06/stealth-behavior-allows-cockroaches-to-seemingly-vanish/

Dena Emmerson is a biomimicry research assistant at the San Diego Zoo. Read her previous post, Biomimicry, Biomaterials, Biometics.


The Answer, My Friend

A capuchin monkey perches on a palm frond as it sways in the wind.

Pop Quiz: What’s invisible, odorless, an unlimited natural resource, and sometimes taken for granted…even cursed upon? Here is a clue: We are now using this renewable resource to produce about 4 percent of our electricity needs in the U.S., and that number is rapidly growing. If you guessed the wind, you’re correct! The almighty wind, a constant and reliable key to our planet’s ecosystem, is so common and present we tend to not even think about it. Now that we are starting to realize its potential, it might be a good idea to look closer at how plants have learned to live with and use it and perhaps learn a thing or two.

Using the wind to disperse seeds is one of the ingenious tactics plants have developed as a survival skill. Lightweight, propeller and parachute-like material attached to seeds represent the most notable and clever use of the wind. Still, there are many other ways. Your idea of the desert may be one of tumbleweeds rolling across the barren, desolate landscape; because deserts tend to be windy, tumbleweed plants have figured out that their best chance of continuing on is to have their seeds dispersed as far and wide as they can. They do this by growing into the shape of a shrubby ball and dying shortly after they set seed. The consistent wind then blows the tumbleweed across the desert, rolling and bouncing, causing its seeds to spread along the way. Using this method, tumbleweeds have figured out the best solution to their problem. Then again, they have had countless years to perfect it!

Another area to look at, and probably more applicable to biomimicry, is how plants protect themselves from the damaging power of wind. Many trees in windy areas have leaves that are thin and narrow, thus reducing the surface area and potential force of strong gales. Palm trees, on the other hand, have developed creative ways to live in harmony with the wind, the most common being in the tissue structure of the petioles (the stems). Here, the petioles are constructed into a crisscrossing mesh of fibrous material, creating a flexible and super-strong tether for the palm fronds and the trunk. What you get is a system that can move and adjust effortlessly as the wind dictates. A possible bio-inspired design could have similarly designed materials for the posts of giant billboards, awnings, or other large stand-alone structures. This could lead to less destruction and death caused by flying debris during hurricanes.

Bonus question time: Where are you most likely to find answers, solutions, and inspiration for many of our current, everyday challenges? Hint: It’s all around us. If you guessed the natural world, you are right, and you, too, are bioinspired!

Seth Menser is a senior horticulturist at the San Diego Zoo. Read his previous post, Seeds Make the World Go Round.


Seeds Make the World Go Round

There is a whole world of wonder inside a fig most people know little of, from fig wasps to seeds.

Every day I get blown away by certain characteristics of plants. There is no lack of drama or intrigue here. From succulents that look like rocks to flowers that smell like carrion to attract pollinators, the botanical world never seems to disappoint. It would be nice to think that plants do this for the pure pleasure of us humans. But this is, of course, not the case. Their reason is simple: survival. I thought it would be fun to look at some of the various ways plants distribute their seeds. Seed development and dispersal methods take high priority and have had a timeless trial-and-error process resulting in ingenious systems for prolonging the species, something us humans could learn a thing or two from!

We all have memories as kids blowing dandelions into the wind. What we were doing was spreading their seeds. Many primitive and early plants used the wind to spread pollen and seeds, and some still do. As more and more creatures roamed the Earth, plants exploited animals to help pollinate their flowers and distribute seeds. (Plant pollination is another fascinating topic that can be explored in a future blog; for now we will stick with the seeds.) With the help of the increasing numbers of fauna, the floral world really began to blossom.

As with most members of the bean family (fabaceae), Scotia brachypetala's seeds are hard and typical looking. However, many can be very colorful!

If you want something to go somewhere, wrap it in a delicious package. That is exactly what fruit does. The fruit attracts animals to take it off to another part of the forest with the seeds inside where they can be tossed aside to germinate. That is the tastiest method of seed dispersal, but many others exist. Take, for example, seeds that have barbs or hooks. They attach to a passing animal and get a free ride for a distance and fall off. Nuts are often collected by squirrels and buried, later to be forgotten about and so become trees. Winged seeds use propeller-like motion to glide away from their parent plant. And even some seed pods explode when touched by raindrops, sending their seeds a good distance away!

The bottom line is that plants need their seeds to be put in a good position to germinate and carry on the species. By these clever techniques, they achieve this. It is an area in the natural world often overlooked but should not be forgotten.

Seth Menser is a senior horticulturist at the San Diego Zoo. Read his previous post, Biomimicry: Nature Deals with Fire.


Biomimicry: Nature Deals with Fire

The seed-laden cones on banksias can survive the flames of a rushing wildfire and use them advantageously. Pictured is scarlet banksia, in Southwest Australia.

I woke up the other morning to the smell of smoke, an unfortunate sign of fall here in San Diego. Luckily, it was a small brush fire and contained before the dry, Santa Ana winds really picked up. It was a sober reminder that we live in a part of the world that has fires. Our fire season is a natural cycle and has been going on for millennia. We are not the only part of the world where fire is part of the ecosystem. Fires can occur all over the world, but in South Africa, Australia, and California, it is a routine. So perfectly, like most things in nature, native plants in these areas have developed ways to grow and even use fire to their advantage.

Fire is destructive, yet it does serve a purpose. It clears vegetation, produces nutrients, and opens up light to the forest floor. Many plant seeds in wildfire country, like conifers and proteas, are enclosed in a fire-proof, protected cone. These cones are designed for fire. A more specific example of this is the beautiful banksia of Southwest Australia. The seed-laden cones on banksias can survive the flames of a rushing wildfire and use them advantageously. The intense heat causes the valved capsules, which contain the seeds, to open up. When the fire passes and the cones cool off, the seeds fall to the ground, ready to become new plants. Because the fire has burned vegetation and let in sunlight, the altered forest floor is now the ideal place for the seeds to successfully germinate; a perfect and well-tested system in this seemingly harsh environment.

A common grasstree in Perth, Southwest Australia, is renewed by a brush fire.

So what can we take away from this? How can we use nature here as our teacher? Well, we already have at least one example of using fire to our advantage, and ironically, it protects us from fire. Sprinkler systems in buildings activate by burning a release mechanism. Once engaged, the water will put out the flames. But we should look beyond this.

There are two options for the millions of people who live in fire-prone areas: either move away or learn ways to deal with this natural occurrence. Since most of us are going to stay, perhaps we can look into paints that change their chemical structures when intense heat is applied and, in turn, form a fire-resistance barrier. This would be a savior for houses and structures. Even reforestation projects could be preemptively done, where native seeds could be set out ahead of time, in nonnative stands of plants, waiting for the inevitable wildfire.

Many good ideas could, once again, come to us by looking at how nature tackles adversity. Our mindset could change so that instead of waking up to the smell of smoke and being in fear, we could be inspired.

Seth Menser is a senior horticulturist at the San Diego Zoo. Read his previous post, Biomimicry: Hope for the Future.


Biomimicry, Biomaterials, Biomimetics

Our armadillo demonstrates the use of keratin, the wonder protein.

On Wednesday, September 28, the San Diego Zoo hosted the second in our series of fall Biomimicry Receptions. This special evening, sponsored by the City of Murrieta, welcomed David Kisailus, Ph.D., and several of his students from the University of California, Riverside, who work on biomaterials and biomimetics. Guests were treated to an after-hours walk through the Zoo to the Treetops meeting room, where wine and appetizers were served while guests mingled with each other and got to know to UC Riverside students. The students gave us some insight into their research through posters and biological artifacts from the animals they work with, such as abalones and marine snails.

Photo credit: Shadow Van Houten

The theme of this evening’s animal presentation was keratin, the wonder protein used to make everything from armadillo scales to rhino horns to human hair. Even though our armadillo ambassador was a bit shy that night and stayed rolled up in a ball, he still had a lot to tell us about the inspiring adaptations found in nature.

Next, City of Murrieta Councilmember Rick Gibbs shared with us all the benefits Murrieta has to offer. All over California there are designated Innovation Hubs or iHubs. Governor Arnold Schwarzenegger spearheaded this initiative in March 2010, and in August 2011 the San Diego iHub was expanded to include Temecula, Murrieta, and part of Riverside. We were excited to have this opportunity to visit with Murrieta and spread the word of biomimicry throughout the range of the Innovation Hub.

Photo credit: Shadow Van Houten

The keynote speaker of the evening, Dr. Kisailus, then shared with guests his exciting research in biomimetics. In his lab at UC Riverside they research the question, “What can biology teach us about the synthesis of new materials?” Current engineering processes tend toward the use of unnaturally high temperatures and environmentally unfriendly methods. Dr. Kisailus is trying to amend these practices by studying the processes that occur in nature. Structures are created at ambient temperatures with available materials and biodegrade at the end of their lifetime. Perhaps even more amazing is that these structures often perform better than our human-engineered products. Abalone shells, enamel, and chiton teeth are among the most abrasion-resistant materials, ranking significantly higher than most human-made metal alloys.

Don’t miss the final reception of the series! We are changing up the location and on Thursday, October 27, we’ll be at the Arnold and Mabel Beckman Center for Conservation Research, on the grounds of the San Diego Zoo Safari Park. This LEED-certified building houses the San Diego Zoo Institute for Conservation Research, the largest zoo-based research effort in the world. This reception will feature Richard Lieber, Ph.D., of University of California, San Diego, who will be speaking to his experience linking animal biomechanics to orthopedic surgery. Please visit our Biomimicry website for more information and to register.

Dena Emmerson is a biomimicry research assistant at the San Diego Zoo. Read her previous post, The Da Vinci Index.


You’re Invited: Biomimicry Receptions

It has been more than a year and a half now that San Diego Zoo Global staff members have been contributing monthly articles in the Conservation Beat e-newsletter (sign up here!) and in the Biomimicry Blog on their thoughts regarding biomimicry. Biomimicry is learning from nature, and we often think of it as bio-inspiration because of the tendency to be inspired by nature.

Various employees have written about what inspires them, and that inspiration is reflected in different ways. Articles have included nature’s influence on business, architecture, robotics, the economy, and health care. In different articles the inspiration has included pandas, bamboo, swarm intelligence, butterflies, coyotes, Mang Mountain pit vipers, and kingfishers.

Besides the articles in Conservation Beat, another treat for folks close to us is to attend one of our Biomimicry Receptions at the Zoo or at our Beckman Center for Conservation Research. Periodically we have these wonderful evening events with a speaker talking about his or her connection to biomimicry and how it is positively affecting their profession, industry, or efforts.

These social events tend to be about two hours in length and are special evenings for all who attend. The next two events have the potential to fascinate their audience with brand-new examples of the application of biomimicry. How is this for a summary of our next talk on Wednesday, September 28, at the Zoo?
“Shrimp-inspired body armor. Nano-scale energy generation. David Kisailus, Ph.D., and his students look to nature in designing the next generation of engineering products and materials.” Sounds fascinating, doesn’t it? Our speaker, Dr. Kisailus, is from University of California, Riverside.

Then on Wednesday, October 27, at the Beckman Center, Richard Lieber, Ph.D., will give a talk involving examples of how bio-inspiration is positively impacting his work in musculoskeletal research at the University of California, San Diego.

Here is a link to the Biomimicry Reception page on our website:

Hope to see you there!

Jon Prange is the venture business manager for San Diego Zoo Global. Read his previous post, Biomimicry: City of San Diego Collaboration.


The Da Vinci Index

What innovations does the tamandua inspire?

“Biomimicry is one of the most promising scientific fields that could transform the way goods and services are designed, produced, transported, and distributed,” said Lynn Reaser, Ph.D., chief economist at Point Loma Nazarene University’s Fermanian Business and Economic Institute. On Wednesday, August 24, Dr. Reaser presented this exciting news at a special biomimicry reception hosted by the San Diego Zoo, unveiling the Da Vinci Index.

The reception, first in a fall series of three, was held on a lovely summer evening at the San Diego Zoo. Guests took a stroll through the buzzing Nighttime Zoo to the Treetops meeting room, where appetizers and wine awaited them. After a period of getting to know other guests, everyone was called inside to meet a special animal ambassador, a South American tamandua. Guests learned about the tamandua’s unique adaptations and were then called upon to come up with their own innovations—there were an impressive number of tamandua-inspired technologies suggested!

Next, Dr. Reaser took the stage and introduced guests to the Da Vinci Index. Named after famed inventor and early “biomimicrist” Leonardo Da Vinci, the Index looked back over the past decade at biomimicry-related activity and tracked some exciting growth in just 10 short years. Starting in 2000 with a baseline number of 100, the Index measured at 713 by 2010! The Index serves the important purpose of providing a tangible means of measuring the field. It has four components: scholarly articles, patents, grant money awarded, and grant money spent. Tracking these four components gathers an ongoing and accurate sense of activity. The Index will be available on a quarterly basis. There is a very positive trajectory for biomimicry products, companies, and research, and the Da Vinci Index is a significant move toward the establishment of it as a legitimate field for venture capital, scientific research, entrepreneurship, and academia, among others.

Point Loma Nazarene University and the San Diego Zoo, along with CONNECT, the City of San Diego, San Diego State University, University of San Diego, and University of California, San Diego are members of Biomimicry BRIDGE, a San Diego-based collaboration promoting biomimicry in business, research, innovation, design, governance and education. The Da Vinci Index, the first product of the BRIDGE group, is an exciting step in the growing field of biomimicry.

The next biomimicry reception will be on Wednesday, September 28, 2011, and will feature Dr. David Kisailus of University of California, Riverside, who will speak to his research in biomaterials and bridging biology with engineering. More information can be found on the biomimicry section of our website.

Dena Emmerson is a biomimicry research assistant at the San Diego Zoo. Read her previous post, Pandas, Bamboo, and Biomimicry.


Pandas, Bamboo, and Biomimicry

Bai Yu shows off a paw adapted for bamboo holding.

This summer the San Diego Zoo’s gates stay open a little later, and guests have the opportunity to hang out with their favorite animal friends longer than usual. Our Nighttime Zoo theme, China Celebration, offers a great opportunity to explore the inspirational adaptations of Chinese plants and animals. The process of studying biology in order to gain inspiration to be applied to human design is known as biomimicry or bioinspiration.

Starting with the most popular ambassador of China that we have at the Zoo, our giant pandas are quite the anomaly of the Animal Kingdom. Though their digestive systems and taxonomic classification hint that they should be carnivorous, they are instead so famously partial to bamboo. They even have a specially adapted “thumb” to grasp bamboo stalks as they strip the leaves. This “thumb” is not really a thumb at all but a modified wrist bone, giving pandas the odd appearance of having six fingers on their front paws. Astronauts, with their puffy space gloves, can’t grip nearly as well as our furry black-and-white bears. Just think how effective a robotic panda paw would be when repairing structures in space.

Almost as interesting as the pandas in the realm of biomimicry is their staple diet item, bamboo. Bamboo is a sustainable wood resource AND a source of inspiration for stability in structure. The round, hollow tube of bamboo provides support that allows the stalks to grow very tall and thin without snapping in half. As bamboo bends, the circular cross section bends into an oval, allowing flexibility in order to keep the stalk intact. Bamboo, unlike other plants, has a unique site of photosynthesis. While most plants use leaves as their solar collectors (bamboo included) bamboo plants also have chloroplasts on their stalks. Taking hints from bamboo’s strong structure and efficient use of space can provide inspiration for the design of future buildings.

Another creature from China, just as important to the ecosystem but significantly less cuddly than the panda, is the Mang Mountain pit viper, which will soon be exhibited in the Zoo’s new Panda Trek habitat. This venomous snake is part of a subfamily known and named for its infrared-sensing tissue contained in pits located between their eye and nostril. The Mang Mountain pit viper is a beautifully colored snake with alternating ragged bands of green and brown with the last ten inches or so of its tail a very light blue, an adaptation used to lure in prey. Once prey is unfortunately close (from its perspective) the pit viper strikes and pierces its prey with its almost inch-long fangs. Vipers have astonishing control over their venom secretion, a beneficial trait to conserve a precious and energy-intensive resource. They can release venom through the left fang only, the right fang only, both fangs at once, or none at all. They do so by flexing a muscle near the venom sac that expels the liquid out of the sac and down a tube ending in the fang. Snake locomotion has already inspired several different robot prototypes, but studying venomous snakes and their venom injection system could also inspire new responsive, resource-conscious liquid dispensers.

There are many other inspiring animals from China and from around the world at the San Diego Zoo and San Diego Zoo Safari Park. Who knows, maybe for your next invention you will be crediting a panda as a consultant!

Dena Emmerson is a biomimicry research assistant at the San Diego Zoo. Read her previous post, Nano-inspiration: Small Size, Big Potential.

Be sure to visit our Biomimicry section for more information about this exciting field of study.


Biomimicry: Hope for the Future

Meerkats have dark hair around their eyes to protect them from the sun.

We live lives of convenience and ease. Our forefathers and mothers would be astonished at the technological and scientific advances we have made in the last 100-plus years. Diseases have been cured and communication has become instantaneous. In this short time, we have gone from using horses and boats for transportation to cars, trains, airplanes, and even spaceships to take us even further. It is unprecedented that we can now get to the other side of the world in less than a day. If we could go back in time and show people in the 1800s what life is like today, we would probably be laughed out of town. Yet all these achievements have come at a cost. Much of our planet’s flora and fauna have become endangered, and in many cases extinct, because of the depletion of natural resources and environments. Even our medicines today are becoming less and less effective as viruses are building resistances to them. The tide of thinking has changed for the better, recently, in solving tomorrow’s problems as the idea of using the natural world as our teacher has replaced our drive to contain and alter it. We call this “new science” biomimicry, and it is undoubtedly going to be the next major element toward shaping our future in a sustainable and responsible manner.

The idea of using certain desired characteristics of plants, animals, and organisms is not new. In fact, if you go back in history you will see many examples of this, from using palm fronds, which repeal water, as roofing on shelters to Leonardo da Vinci observing birds in flight and developing his concepts of “flying machines.” Even today such simple examples of biomimicry exist, and we probably don’t make the connection to the natural world. Just look at football and baseball players on sunny days: many of them put black grease under their eyes to protect them from the sun, as the black color absorbs the sunlight, giving them better vision. Dark colors around eyes can be observed in many diurnal animals, most famously the meerkat. Meerkats need this protection, for they spend a good part of their days with their eyes to the sky on the lookout for predatory birds; in southern Africa, where they are from, the sun is plentiful.

Looking back, we have a clearer picture of the damage we have done to our environment. The common consensus is that we need to move in a different direction toward tomorrow or lose everything. Using the natural world as our classroom makes perfect sense. Plants, animals, and organisms have been hard at work for a few billion years, perfecting solutions for problems. Why would we need to look anyplace else? Biomimicry offers us a whole new world of possibilities and answers. It is a step in the right direction; actually, it’s the “natural” choice.

Seth Menser is a senior horticulturist at the San Diego Zoo. He will be contributing periodical blogs on biomimicry, with an emphasis on the botanical world. Read his previous post, Caudiciforms: Botanical Camels.

Learn more about the exciting field of biomimicry.