With global climate change a serious threat to human existence, saving energy is of crucial importance. Air resistance – or “drag” – is the main force that causes fuel waste. The most important factor in drag is the “drag coefficient,” which is mostly dependent upon the shape of a given object. Objects whose shapes do not sharply contrast the air’s flow lines, and which render the changes in flow lines regular, have lower drag coefficients. In all creatures that move quickly through the air and water, their bodies are perfectly designed to keep their drag coefficients low. Unfortunately, research into these designs is just beginning. Scientists are just starting to study the geometries of certain creatures, in an effort to utilize their shapes to design more efficient vehicles.

The white, or Beluga, whale, has a perfect shape to facilitate its movements in water. Its beaky mouth and characteristic blunt head decrease drag, in spite of its bulky body.

In 1994, Airbus designed a cargo plane to carry very large cargos. As a cargo plane requires an ample interior, it also needs the right design to lower air resistance. In its design, Airbus imitated Beluga whales, which are both very large – and very aerodynamic. As such, the plane became known as the Airbus Beluga. In a major departure from normal plane design, a wider fuselage section, which resembles a bubble or hump, was added to the top of the Beluga. This extra space allows the plane to carry very large loads, such as helicopters, satellites, and plane wings. The plane, which weighs 86 tons when empty, has the capacity to carry loads up to 47 tons.

The Columbus Satellite, being sent from Germany to Nasa, in Florida.

The plane has been so successful that in order to meet increased demand, the company is planning to build a similar but larger plane, the Beluga XL.

The protuberances on the head and flips of a humpback whale.

In addition to the hump of the Beluga whale, designers have discovered that the rounded fins and heads of humpback whales provide a 10% decrease in drag, and a 5% increase in buoyancy (figure 4). They’ve incorporated these features into the design of next-generation helicopter blades. When a helicopter flies, the blade that spins forward is faster than the blade spinning backward. This situation causes the blade moving backward to temporarily lose lift. Together with turbulence, an extra load is brought to the rotor and the controlling rod, and this decreases the speed and maneuvering ability of the helicopter. In order to solve the problem, the back blade needs to be improved. Humpback whales inspired the solution. German aviation researchers placed 186 rubber protuberances, 6mm in width, on each blade. After good results from wind tunnel experiments, they made test flights and obtained recognizable enhancements in performance.

Thanks to the protuberances, the working angle of the propellers increased from 11 degrees to 17 degrees, and the performance increased 40% (figure 5).

Researchers witnessed a similar increase in performance when using the same principles for hydraulic wind turbines.

These are just a few examples of what seem like simple, overlooked qualities in nature that can actually inspire engineers, leading to major technological breakthroughs. We would all benefit from more scientists conducting research on this topic. The wondrous perfection of living creatures allows aircrafts – and our spirits – to soar to new heights.

When designing the next generation of planes, engineers would be wise to look to the sea, where whales offer up a perfect blueprint for decreasing drag and increasing performance.

References

• http://www.gizmag.com/humpback-whales-rotor-blades/21332/
• F. E. Fish, P. W. Weber, M. M. Murray, L. E. Howle, The Tubercles on Humpback Whales’ Flippers: Application of Bio-Inspired Technology, Integrative and Comparative Biology 51 (1), 203-213, 2011.
• T. Gruber, M. M. Murray, D. W. Fredriksson, Effect of Humpback Whale Inspired Tubercles on Marine Tidal Turbine Blades, ASME Paper No. IMECE2011-65436, 851-857, 2011, doi:10.1115/IMECE2011-65436

I am sure that there are a lot of people who’ve found themselves in a similar situation to the man above. Unfortunately, most of us are usually not aware of the things happening in this universe. One of the things we tend to overlook is the cleanliness of nature. This is a topic which needs to be considered carefully, but I will just touch on some important aspects of this issue.

First, let’s look at the oceans. The oceans cover three-fourths of the Earth’s surface. There is a bigger world under the ocean than above it. This huge mass hosts jelly fish and tuna, dolphins and octopus, crabs and plankton, sea stars and sea plants. Currently, there are 120,000 species living in the ocean. This is just the number of the species, and doesn’t account for how many variations there are within each species. When we consider the number of living organisms, there are millions of them. Every single day, lots of these organisms die. If there are millions of organisms and thousands of them die each day, then why cannot we see them on the surface of the ocean? Even if these dead organisms are very small, such as plankton, which has a size range from 0.2 m to 20mm, when millions of their dead bodies cluster on the surface, we should be able to see them. The answer lies in a perfect arrangement. For example, the job of cleaning the dead bodies of plankton (also the live bodies!) is performed by fish, sharks, and whales. A large percentage of the daily diet of these animals depends on plankton. Since these animals perform their job well, it is impossible to see any dirt that would have been caused by the dead plankton.

It might seem easy to get rid of the dead bodies of plankton, because they are small organisms. But what about big animals such as whales? What happens to dead whales? Let’s consider the cleaning of dead whales. When a whale dies, its dead body sinks to the bottom of the ocean. This is called a “whale fall” by scientists. There are a lot of species whose diet depends on dead whales. In 1988, a group of researchers at the University of Hawaii found that there are at least 12,490 single organisms which supply their daily diet from a whale fall in the deep North Pacific Ocean. After bigger organisms, such as fish, finish their job, which includes eating the flesh of the dead whale, the other cleaners come to the scene to perform their roles. At this part of the fall, bacteria play a key role in cleaning the bones left from the whale fall. This is not as easy as it might seem. Actually, it takes several years to really clean the dead body from the bottom of the ocean. This is not just a cleaning process at all. While the whale fall is being cleaned from the bottom of the ocean, the ecosystem is supported by the energy from the dead whale.

This cleaning process is not only seen in the oceans, but also on the land. Even though it is more apparent than undersea, we are not totally aware of the cleaning process on land. Decomposition is the chain of events by which a dead organism breaks down to its smaller parts. We must stop here and ask this question: “What would happen if these dead organisms stayed on the land forever?”

So let’s look at what happens to a dead animal on land.

When an organism dies, the process of decomposition starts shortly after its death. There are some stages in the decomposition of an animal. Shortly after the death of the organism, the enzymes in the cytoplasm of the cells start to break down the tissues. This process is called autolysis. It is one of the stages of decomposition in which bacteria plays a role. Bacteria start to break down the tissues. This is called putrefaction. Bacteria are not the only players who have roles in this process. Besides them, some fungi, insects, and even some carnivores are also involved. Live animals, water, air, and temperature (higher temperatures increase the decomposition rate) also help this process. During this time, fungi and bacteria, by using compounds from the dead organisms, convert carbon to carbon dioxide and organic nitrogen to ammonium (NH4+), and so they contribute to both the Carbon and Nitrogen Cycle. After this process is done, many organisms living in the ecosystem have benefitted. At the end of this cycle, soil is enriched with new nutrients which will help the new plants to grow up and the Carbon and Nitrogen cycles are enhanced.

By looking at the processes above, as well as other cycles (e.g. the Carbon cycle), it can be said that the Earth has its own recycling system. While modern societies have only recently understood the importance of recycling, Earth has been using this system thanks to the arrangements given to it.

The things shown here are just some examples of the extraordinary systems existing on the Earth. These systems have always been like this, since the very beginning of the universe. These perfects systems in nature perform their tasks without any human help. The only thing for us to do is to appreciate this harmony, understand its value, and keep it going for the next generations.

Original Article: Ichinohe T. et al., PNAS (published online before print 2011).

Influenza, also known as seasonal flu, affects up to 5 million people annually. Flu viruses infect and damage the animal respiratory tract, especially the lungs. Upon flu virus infection, a life or death battle between an animal’s immune system and the flu virus begins. To defeat the flu virus, the animal’s immune system synthesizes important flu-fighting molecules. Researchers at Yale University discovered that mice on the antibiotic regimen, a treatment that wipes out certain bacteria which normally live in the guts of the animal hosts, showed deficiency in immune responses against flu virus in the lungs compared to mice that had not been treated. This finding suggests an unexpected link that the bacteria living in the animals seem to control the production of these flu-fighting molecules. These commensal bacteria, or good bacteria, prime the immune system in making flu-fighting molecules even before infection, and this priming is important for subsequent flu-fighting strategies. The exact bacterial species that helps fight the flu are yet to be identified. It is interesting to contemplate why the immune system trusts bacteria with such an important job. Whatever that reason might be this finding warns against misuse or abuse of antibiotics. We don’t want to kill the good bacteria that might just protect us in the next flu season.

2- Less talking with longer words

Original Article: Piantadosi S.T. et al., PNAS 108, 3526 (2011).

What factors affect the length of a word? Do we prefer to use short words or long words while we are talking? For many years, researchers believed that the most frequently used words tend to be short in order to make the language more efficient. It is intuitive when we think of words such as “a,” “the,” “but” and their popularity in our everyday life. However, according to a recent study done by Piandatosi and coworkers in the Department of Brain and Cognitive Sciences at MIT, the length of a word reflects the amount of information it contains. They observed that people use many words in predictable sequences along with other words in their daily life. Most of the time a short word may not contain information per se, but carry information as a collection with other familiar words. This observation led the researchers to look at the problem from an ‘information content’ perspective. A word is said to have more information if it is less predictable in a sequence. An analysis was done on the Google text database in 11 different languages. The results show that word length closely correlates to information content. Once again, it is not important how much you talk. It is important how much you mean.

3- Ups and downs of sleep with alpha waves

Original Article: McKinney S.M. et al., PLoS One 6, e17351 (2011).

Why do we randomly wake up in the middle of the night? Searching for an answer for this question, researchers at the Massachusetts General Hospital (MGH) discovered a brain rhythm that determines one’s susceptibility to disturbance by the outside world while asleep. Scott McKinney and his colleagues conducted a study where they analyzed the electroencephalographs (EEGs) of 13 volunteers, who spent 3 nights in MGH’s Sleep laboratory. EEG devices use electrodes on the scalp to detect electrical activity in the brain. There are four major brain waves that can be detected by EEG: alpha, beta, delta and theta waves. Alpha waves usually emanate from the back of the head during relaxed wakefulness, particularly when your eyes are closed, and they are thought to gradually disappear when a person goes to sleep. Researchers developed a special computational method that can probe EEGs in much deeper data resolutions. Their analyses revealed that alpha waves never disappear during sleep; they just go below conventional detection levels. Moreover, when alpha wave activity spikes just before an obnoxious auditory stimuli (e.g., loud talking or traffic noise) is played, volunteers seems to wake up more easily than when alpha wave activity was low. These findings suggest that maybe the alpha wave activity is the brain’s way of keeping us aware of our surroundings during sleep, and perhaps it enables us to wake up quickly in case of danger. Of course, too much alpha activity might also have a downside: it can make you a light sleeper and give you restless nights.

4- Killer whales imitate enemies and friends

Original Article: Wei B.M. et al., Marine Mammal Science (published online before print 2011).

In marine mammals, as individuals frequently cannot see each other, sound is particularly important for communication. Killer whales live in groups or clans, and these different clans have their own dialects. A recent study showed that whales can do more than just talk in their own language: they can mimic calls from other groups with a different dialect. While analyzing the social behavior of wild orcas living near Vancouver Island in British Colombia, a group of researchers from the University of Vienna discovered that resident whales occasionally produce call types from the repertoires of other vocal clans. The calls resemble the calls of foreign groups that the original group interacted with before. When different clans are in close proximity, it is quite challenging to reliably distinguish original calls from resembling calls. For this reason, researchers recorded calls that resemble call types of a different clan in the absence of that clan and compared them to the originals of the respective call types by analyzing their sonograms. Sonograms reveal distinctive information about the structure of the sound waves, i.e. the spectral density of these signals, and this information can be used to classify animal sounds. The comparative analysis clearly shows that killer whales can imitate calls from other groups even when members of that group are not around. Researchers suggest that this could be a way of labeling outsiders or keeping tabs on their location. Maybe by impersonating the calls of a group, they are conveying a message about that group to their own family members. It is exciting to see that vocal mimicry is not limited to songbirds and dolphins, and that killer whales have more complex social lives than we previously thought.