Introduction
Scientists have been solving problems and finding solutions to human challenges for centuries. Biomimicry is a branch of science that uses nature as a model to solve such problems. For example, the U.S. Navy enlisted scientists to develop a way to prevent algal growth on submarines. A look into nature showed that sharks had already perfected the design the scientists needed. Through biomimicry, scientists develop innovative approaches that seek solutions to human challenges by copying nature’s strategies.
Background
Many challenges humans face are similar to challenges that other organisms face and have faced since life began. The rapid-growing field of biomimicry has scientists examining the processes used by nature to find solutions to human problems.
Velcro® is a classic example of biomimicry at work. In 1941, as Georges de Mestral, a Swiss engineer, was walking with his dog through the woods, he noticed that burrs covered his pants as well as his dog’s fur. Rather than being frustrated, de Mestral looked at the tiny burrs and thought this might be something useful. After 8 years of research and prototyping, Velcro was created—two strips of fabric, one with thousands of tiny loops, the other with thousands of tiny hooks. Velcro has been used in a multitude of industries, from shoes to toys to technology to NASA and the military.
Let’s take a closer look at the example of biomimicry that began with the U.S. Navy seeking a solution for algae growth on their submarines. As submarines and ships move through the ocean, marine organisms such as algae and barnacles accumulate on their surfaces, making the ships less fuel efficient. Biomedical engineer, Anthony Brennan, observed that whale and manatee skin also accumulate algae and barnacles; however, sharks do not. Looking at shark skin under the electron microscope, he saw a unique pattern to the denticles or scales. Brennan believed the diamond pattern on shark denticles prevented microorganism growth. He designed a thin plastic coating with the denticle pattern, attached it to the ship, and the growth of microorganisms was inhibited.
This concept of preventing micro-organismal growth on surfaces is a challenge for the healthcare industry as well. According to the U.S. Centers for Disease Control and Prevention (2011), secondary infections acquired during hospital stays affect an estimated 722,000 patients, with approximately 75,000 resulting in death. Anthony Brennan took his concept from naval ships to hospitals. Brennan’s Sharklet™, the micropattern of ridges designed to mimic shark skin, harbored 94% fewer MRSA bacteria than a smooth surface and was more effective than copper, a leading antimicrobial material, which kills bacteria by interfering with cellular processes. Sharklet™, however, does not kill the bacteria. Instead, the pattern and texture of the surface impede the bacteria’s ability to attach. This “unattachable surface” mimics the unique adaptation of shark skin. The Sharklet™ material is designed to attach directly to surfaces of plastic products that surround patients in hospitals, such as wristbands, handrails, side tables as well as medical devices. Instead of using new products, the shape and texture of the existing materials are altered to create an unwelcoming surface for microbial inhabitants.
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These examples show how a look at nature provides solutions to problems humans face daily. Biomimics are investigating how other creatures may have solutions to problems we face. Biomimicry solutions do not harvest the creature or its byproducts, but rather copy the idea, design or recipe and create a new product.
Materials
Balance
Ice water
Plastic spoon
Plastic utility pail
Recloseable bags, 6" x 12", 2 per person
Rubber bands, 2 per person
Timer
Vegetable shortening
Weigh dish
Safety Precautions
Remember, all food items brought into the lab are considered chemicals and are not to be consumed. Remove your hand from the ice bath when you feel any discomfort. Wash your hands thoroughly with soap and water before leaving the laboratory.
Procedure
Part A. Biomimicry and Insulation
Control Data
- Fill the utility pail about one-third full of water and ice and allow to chill.
- Place one hand into a plastic bag and make a fist. Release any trapped air and put a rubber band around the bag and your arm near your forearm. This is the control hand.
- Place the bagged hand into a second plastic bag. Release any trapped air and put a rubber band around the bag and your arm near your forearm.
- Set the timer to zero. At the same time, all group members should place their bagged hands into the ice water and begin timing.
- Leave your hand in the water until you are uncomfortable. Note: The time is recorded to the nearest second.
- Record the time each hand was in the ice water.
- Remove the plastic bags and rubber bands and retain for later use.
Experimental Data
- Measure 50 g, 75 g or 100 g of vegetable shortening. Place the vegetable shortening into one of the plastic bags.
- Place the opposite hand (not the control hand) into an empty plastic bag and make a fist.
- Secure the plastic bag with a rubber band around your forearm as before. This is the experimental hand.
- Place the experimental hand into the bag with the vegetable shortening. No vegetable shortening should get on your hand.
- Squeeze the outer bag in order to surround your hand with the vegetable shortening as evenly as you can.
- Set the timer to zero. At the same time, all group members should place their experimental hand into the ice water and begin timing.
- Leave your hand in the water until you are uncomfortable. Note: the time is recorded to the nearest second.
- Record the time each hand was in the ice water.
- Remove the plastic bags, vegetable shortening and rubber bands and discard in the trash.
Part B. Biomimicry Design Challenge Design and engineer a product that solves a human challenge using nature as the primary resource. As a biomimic, use nature’s blueprint or recipe to synthesize a product that could be utilized by humans.
