by Gordon Wade '15 Shark skin has so little drag that Speedo has made swimsuits with materials designed to imitate shark skin. [image via]
Evolutionary solutions to natural problems are often more effective than designed solutions. Biomimicry allows us to adapt these evolutionary concepts into great engineered designs. Sharks, for example, have evolved toward extremely high efficiency in traveling through water, meaning reductions in energy usage and increases in speed. Their physical skin design lowers drag forces associated with movement and has shown great potential for application in human transportation.
Sharks are peculiar in that they live in an aquatic environment and never stop moving. Because of this, they must find effective ways to transport themselves through fluids. One adaptation lies in the small-scale structure of their skin. Under a microscope, the surface of shark skin is seen to comprise thousands of small teeth-like structures called denticles. These denticles manipulate fluid dynamics in order to decrease drag.
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by Elena Suglia '15 Most people know that bats use echolocation to find prey and orient themselves in space, but did you know that bats use echolocation to communicate with each other? It turns out that there’s music in the air every night, except we can’t hear it! It’s a good thing too, because the intensity of the sound waves bats create would be deafening could we hear them. A bat’s screech, though inaudible to us, “rivals the intensity of a revved-up engine of an aircraft about to take off” [1]. Think whale or dolphin song: that’s what bats do, except at super ultrasonic frequencies which human ears are unable to decipher. This makes intuitive sense when you consider what high- and low-pitched sounds are made of: sound waves with different frequencies. Sound waves with high frequencies bend less as they travel and can therefore be used in a more precise manner to target an object. Bats use higher frequency waves because they operate in tight spaces and need to be more aware of their immediate surroundings so that they don’t run into obstacles or lose track of a quickly moving, small insect [2]. Whales use lower frequency sound waves because they live in the open ocean, where they have much more space in which to maneuver. by Elena Suglia '15 Dolphins and other cetaceans are some of the most well-loved, charismatic creatures on Earth. This stems in part from the many human-like qualities they display. Some dolphins recognize themselves in a mirror [1], call each other by name [2], and correctly identify and communicate to humans the presence or absence of objects in their tank [3]. Their intelligence intrigues citizens and scientists alike, and cetaceans have earned a reputation as some of the world’s smartest animals. by Denise Croote '16 This three-minute clip tells the timeless tale of predator and prey, of a bright-eyed and bushy tailed young squirrel eager to take on the world and a particularly malicious hawk hungry for lunch. In a way, we were all bright-eyed, bushy tailed squirrels simply trying to enjoy the Brown experience, until all of these midterms just before Spring Break tried to eat us. Nevertheless, survive we must and prevail we shall. If you've ever wondered about the facial expressions of a squirrel as a hawk is shaking it from a tree, this video has your answer. If you could care less about a hawk-squirrel hunt, this video will still astound you with its HD 1080p resolution. How this was caught on film is a complete mystery. Good luck, fellow squirrels! (If you're a hawk, well, good luck to you too, but please don't eat me.) by Miranda Norlin '17 You've probably noticed Cornus kousa, those trees around campus that drop round, reddish-pink knobbly fruit. Commonly called Chinese, Japanese or Korean dogwood, C. kousa is widely sold both as an ornamental and as a fruit tree. The species can be identified when not in bloom or fruiting by their distinctive leaves whose veins originate from the center of the leaf and run parallel down to the tip. Though this pattern is distinctive, using the leaves to identify dogwoods around campus might leave you a bit confused. If you wander towards RISD, you'll encounter Cornus florida, the rather different flowering dogwood native to the eastern US. The leaves are very similar, but their fruit, a shiny, compact red berry, is toxic and looks distinctly less appetizing than those of C. kousa. These trees are valued on campus for the lovely white flowers they display every year. Traditionally, Native Americans and soldiers in the civil war used the bark and roots of C. florida as a treatment for malaria. Recent studies have confirmed the presence of antiplasmodial compounds (compounds effective against the plasmodium parasites that cause malaria) but suggest other factors must contribute to the purported anti-malarial effect because the antiplasmodial compounds found are not strong enough to explain the dogwood’s historic use. Further research might reveal chemicals that support the immune system or reduce fever (1). Until such medicinal value is confirmed, Brown students will have to be satisfied with consuming C. kousa fruit and appreciating both on-campus Cornus spp. for the flowers they were originally intended to provide.
by Noah Schlottman '16 Sometimes, there seems to be an endless supply of readings, homework, lab reports, and projects. If you’re ever in a slump because of the demands of school and those sixteen student groups you’re involved in, at least there’s one thing you’ll never have to worry about: being eaten. Eating and being eaten are the two biggest problems for pretty much every other organism on the planet. What’s worse is when whatever is eating you is also eating your food. Welcome to the life of a caterpillar. |