New Music and Your Brain!

Why do we like the music we like?

Think about all the music you've ever listened to.  Everything from Beethoven's 5th to "Call Me Maybe" are processed through the brain, but what about them allows the brain to say yay or nay?  

So, why do we like the tunes we like?  Well, there's no complete answer just yet, but scientists are exploring more and more about our brain and discovering some pretty neat stuff.  

First we must understand that music is indeed comprised of a lot of sound vibrations.  So, before we answer the question about why we like music we must understand that what we are really answering is why certain series of sounds feel better than others.  To answer this question we must dive deep into the human mind.  The brain is comprised of lots of compartments and relays.  One of those compartments is called the auditory cortex, this is the part that stores all the sounds you've heard in your whole life.  Remember those screeching tires, ice cream truck song, hammers hitting nails, the soundtrack to Lord of The Rings…and so on.  All of those sounds are cataloged by the auditory cortex including all the songs and patterns of sound that you've heard in your entire life.  Each person's auditory cortex is totally unique. 

In a recent experiment conducted by the Montreal Neurological Institute and Hospital, the brain was studied to see how the auditory cortex communicates with the accumbens nucleus.   This is the part of the brain that shows signs of reward and pleasure.  In this study they noticed that the accumbens lights up when it hears new music after the song has been filtered through the auditory cortex.  Wait a minute…isn't the auditory cortex different for different people?  Yes, it sure is.  That's why different people like different music.  One possibility is that all the sounds you've ever heard in your life will dictate and determine the desire to hear similar sounds in the shape of new music.  

Your stored and cataloged audio experiences could have a lot to do with how you process your opinions on the new sounds you are hearing.  Pattern recognition and predictions of where the songs go are powerful processes that the brain computes as you hear the new songs coming into your ear for the first time!

The big question now, after more research how will this impact our lives?  Well,  this could be considered the ultimate targeted marketing plan or the ultimate musical survey.  We'll find out as time passes! 

Yet another insight into your complex and unique brain! 

What came first the chicken or the egg?

Science is the process by which we can ask and answer questions about our natural world.  Everything from your most routine activities all the way to the quest for our universe’s origins are fair game for the field of science!  So, let's put science to the test and answer an age-old question: What came first the chicken or the egg?

So without the egg there would be no chicken, right?  However, at the same time without the chicken would there be an egg?  Well, actually, yes there would be.   This is the story about the long and detailed process of evolution. Eggs are used by any species that sexually reproduces.  So to trace back the history of eggs we must look back at some of the earliest species that sexually reproduced.

First of all, some of the earliest eggs date all the way back to early sponges, literally hundreds of millions of years ago.   After millions upon millions of years of natural selection on mutations and variations an early avian species was produced, we’ll call this a “proto-bird”.  This early bird laid eggs that would, again after generation upon generation of natural selection, turn into a wide variety of bird species.

One of those bird species was what we could call a “proto-chicken”, meaning it was some variation of what we know as a chicken, but not exactly what we have available on Earth today.  Well, that “proto-chicken” laid eggs and eventually the species started to morph and change slowly due to natural selection and voila, an egg was laid that would hatch and give birth to what we now know as a chicken.  The egg allowed for the chicken to be born.

Now, why that chicken crossed the road is a whole different story all together...

The Amazing Human Heart!

The Human Heart is pretty amazing! It's the power house of our circulatory system. One muscle with four chambers that pumps about 1900 gallons of blood every single day!  That's pretty impressive considering that this vital organ only weighs about 10 ounces.  Don't let size fool you though, the heart's work goes a long way, literally!  The average adult human circulatory system can actually reach about 60,000 miles. That's enough to wrap around the Earth four times!! On top of all this, as if that were not impressive enough, the human heart will beat about 3 billion times in a full lifetime!  Pretty impressive! No wonder we all <3 the human heart!

Question Your World - Valentine's Day special! Mate for life!

So, we sure do celebrate loyalty, companionship, and romance on Valentine's Day. We're not the only species that shares similar sentiments. Did you know some animals also mate for life? Wolves and Termites are just two of the many animals that mate for life! Its good to know that there are strong bonds of loyalty from nuclear family mammals to insects that pine for one another.

Want more examples of animals that keep that one special main squeeze? Check this out! :Mate for life list!

Question Your World - Breathing

Question Your World - Breathing by ScienceMuseumofVA

Our bodies are pretty amazing and complex! A lot of the involuntary actions that we do every single second keep us alive and healthy. Breathing, for example, is one of the most basic functions of the human body. So, how often does a person do this? Well, on average about 15 times a minute! This varies based on activity level, but on average we are clocking in at around 15 breaths per minute. Check it out, do an experiment, try to count how many times you inhale/exhale in a minute. Try it while laying down, sitting up, walking, maybe even running.

"Turkey Day" Trivia

Want to wow your guests at the Thanksgiving dinner table with your incredible knowledge of turkey trivia?  Check out these "Turkey Day" facts! 

• Most farm raised turkeys are White Hollands. They cannot fly.
• An adult turkey has about 3500 feathers. Big Bird’s costume (from Sesame Street) was made from nearly 4000 white turkey feathers, dyed yellow.
• Wild turkeys can glide almost a mile without flapping their wings. Over short distances, they can fly 55 mph and run 20 mph.
• Acorns are the wild turkeys’ favorite food. Because they have a poor sense of taste and smell, they choose acorns by size and shape.
• A turkey’s head will change colors when it’s excited.
• Wild turkeys spend the night in trees.
• A male turkey is called a tom, the female is called a hen and the babies, poults. Immature turkeys are called jake (male) and jenny (female).
• How to tell toms from hens:
• Toms are larger, have longer legs and bigger heads. Their wattle (growth under the chin) and snood (fleshy growth over the bill) are also longer.
• Toms grow a beard – long black feathers on their chest. The beard grows about 4 inches per year and keeps growing throughout their lifetime. Eventually, it drags the ground.
• Male turkeys gobble and females make a clucking sound.
• During mating season, a male turkey gobbles loudly and struts around, puffing out his chest, fanning his large tail and dragging his wingtips on the ground. 
• As male turkeys get older, they fight a lot and may attack humans. 
• About 180,000 wild turkeys live in Virginia, most of them in the Tidewater, South Mountain and South Piedmont regions. 

Turkey history -

• Wild turkeys are native to the eastern US and northern Mexico.  They have lived in North America for almost 10 million years. 
• Wild turkeys were domesticated in Mexico and introduced in Europe in the 16th century. 
• In the 1700s, turkeys were walked to market and wore booties to protect their feet. 
• Ben Franklin thought the wild turkey should be our national bird instead of the bald eagle. 
• Astronauts Neil Armstrong and Buzz Aldrin ate turkey for their first meal on the moon. 
• Wild turkeys almost became extinct in the early 1900s because of habitat destruction and overhunting. 
• The Turkey Trot was a ballroom dance popular in the early 1900s. The Turkey Trot 10K is a race run every Thanksgiving in Richmond.

Thanksgiving turkey facts –

• Over 45 million turkeys are eaten every Thanksgiving.
• The average American eats 17.5 pounds of turkey per year.
• US turkey production has increased over 300% since 1970.
• Turkey meat is low in fat and high in protein.
• White meat has fewer calories than dark meat.

Meet the Tank: Sea Stars



Science Museum of Virginia sea stars



By Meghan West

Gallery Educator

Science Museum of Virginia

In our “Beach Science: It’s a Shore Thing” exhibit we have a saltwater tank housing some sea creatures that can be found off the coast of Virginia. For those of you who have been to “Beach Science: It’s a Shore Thing” you may have already seen or even touched one of our sea stars. For those of you who have not, let me introduce you.

Sea stars, formally known as starfish, were renamed because they don’t look like a fish, don’t swim like a fish, and are not a fish. Because of this they dropped the name fish and added sea (same thing happened to sea jellies, formerly known as jellyfish). They are in the phylum echinodermata, which means spiny skin and anyone who has touched one or even handled a dead one can feel the bumpy, spiny skin. They are in the same phylum as sea urchins and sand dollars, even though they don’t look a lot alike.

Strange creatures are our sea stars; they have no blood, no brains, and if we chop them up, as long as there is a fifth left, they will grow everything back. As for the no brains thing, anyone who has seen “SpongeBob SquarePants” can attest that Patrick Star, SpongeBob’s best friend, is not the sharpest knife in the drawer. Comedy is not the only reason Patrick is a little slow on the uptake. The creator of SpongeBob, Stephen Hillenburg, taught marine biology at Orange County Ocean Institute in California and puts weird facts like that into the story and characters. Sea stars actually have something going on upstairs, but it’s just a nerve ring instead of a brain.

Breathing is another thing that our dear sea stars don’t do like most of the creatures we come in contact with. They absorb sea water through a small dot normally located somewhere on the top facing side of the sea star; this is called a madreporite. The water they absorb is used in their circulatory system (yes, you read that right, sea water being used for blood). While they have the water they might as well make the most of it and absorb the oxygen out of it.

For vision the sea star uses a tiny dot on the end of each arm to see. If you find a sea star large enough you may notice the tiny dot (it looks like someone put the point of a highlighter on the very tip of the arm). Their vision is not like ours and is more like dark and light (sun’s out - sun’s not out).

To get around, the sea star uses its arms with hundreds of little, tiny tube feet on each arm. None of the arms are dominant. Our Forbes Sea Stars have 5 arms each and have been clocked at a whopping five inches a minute! That is a sea star run! Full speed, petal to the metal, run! (That’s .005 mph.) When you don’t have to run down your food and most things don’t want to eat you or will only take a bite that you will grow back, speed is not a major concern. Their favorite food is most bivalves (animals with 2 shells) like oysters, mussels, and clams. The creatures that they are most concerned about avoiding are crabs, bottom dwelling fish, sea gulls, sea urchins, lobsters and (be surprised) humans.

To eat, the sea star wraps its arms with tube feet around a bivalve. The bivalve slams shut; it doesn’t want to get eaten. After roughly 10 hours the amount of pressure the sea star exerts on the bivalve forces it open, just a little bit. Then the sea star takes its stomach out through its mouth and begins to eat the squishy inside of the bivalve. When the sea star finally removes itself from the bivalve all that is left is shell (licked clean!). Mussels are easily the favorite food of the sea stars in our tank. I am not sure if it’s because they are easier to open or if it’s the fact that they prefer the taste. Our sea stars go through about a pound of mussels in a week. With some of the larger clams in the tank, our sea stars appear to attack them in a group, which amazes me since they have no brain. So I wonder - can they organize? Is it instinct? Communication beyond our understanding? We may never know.

Mysteries of the ocean are being unfolded every day. Remember we know more about the planet Venus than we do about our own oceans. Till the next “Meet the Tank”, take care.

Good-bye, ospreys! See you next year...

If you spend much time on the Virginia coast, the high-pitched call of the osprey is a familiar sound. In fact it’s so familiar that it’s often taken for granted …until it’s gone. I love fall with its cool sunny days and blue, blue skies, but I am always a little sad when the ospreys leave. Around mid- September, the ospreys who summer on the Chesapeake Bay disappear. Where do they go?

Dr. Richard O. Bierregaard, Jr. knows! He has been studying ospreys for over 40 years. In 2000, in collaboration with Dr. Mark Martell, he began installing GPS tracking devices on young ospreys to track their migration patterns, including several from the Chesapeake Bay region. Ospreys have been tracked to winter quarters in the Caribbean, Central and South America, as far south as Peru! His tagged birds have names and his website is updated regularly with their progress. By September 12, three birds, Penelope, Sr. Bones and Thatch (Thatch is from Delaware) had begun the long and perilous journey south. Gunny left on September 19 and arrived in Virginia Beach on Tuesday. Other tagged birds, including Neale, Sanford and North Fork Bob, should be leaving soon. To follow their progress, go to: http://www.bioweb.uncc.edu/bierregaard/migration10.htm.  I have to admit that following these birds as they make their way south and, hopefully, back north again could become an addiction.

If they survive the journey and winter, they will return around mid-March to nest near the area where they were born. Ospreys begin mating at three years of age and will often mate for life. Nests consist of bulky piles of sticks on navigational markers, duck blinds, utility poles or high up in a pine tree, but always near the water. Females usually lay three eggs in mid-April to late May.  By July, the fledglings fly from the nest and begin to practice their steep dives to catch fish.

Ospreys are sometimes confused with bald eagles. It’s certainly easy to do – ospreys look remarkably similar to both juvenile and adult bald eagles. Here’s a brief primer to tell them apart: ospreys are dark brown or black with white underparts, a broad black eye stripe and a black patch on the underside of the wings. Adult bald eagles have white heads and tails but dark underparts, while juvenile bald eagles are all brown or mottled brown and white all over. Ospreys are slightly smaller than bald eagles and fly with their wings "crooked" in an M shape, whereas bald eagles fly with their wings in a flat line.

We are fortunate here in the Chesapeake Bay region to have the largest nesting population of ospreys in the world, over 2000 pairs which accounts for 25% of the US population. While they are wintering in warmer climes, I hope to follow the travels of Penelope, Sr. Bones, Thatch and Gunny and will eagerly await their return in the spring!

A Webworm Horror Story

Last Sunday I decided to enjoy the beautiful fall weather and eat my lunch outside. About halfway through my sandwich, I glanced up to see something fuzzy crawling down my bangs onto my nose – UGH! It was a fall webworm – you know, those nasty hairy caterpillars whose giant webs appear on tree branches every fall? There seems to be a bumper crop this year – caterpillars are crawling on everything: across yards, along sidewalks, up walls, on decks and porches… you get the picture. When I went outside to eat, I purposely positioned my chair away from the trees to avoid them (and to avoid the occasional falling walnut – ouch!). This fellow found me anyway and sort of put me off my lunch.


Description of Damage
In the grand scheme of things, fall webworms do not do a tremendous amount of permanent damage, although the webs are definitely unsightly. Caterpillars feed on leaves inside the webs, gradually enclosing more foliage as they grow. Heavy infestations may defoliate a tree but rarely kill it. Over 100 species of trees play host to these voracious pests, but here in central Virginia, they seem to prefer nut and fruit trees, such as walnut, pecan, cherry and crabapple.

Life cycle

The adult moth is snow white, often with dark spots, and somewhat hairy (not surprising, considering the caterpillar). They lay their eggs on the underside of leaves in May through July. The larvae hatch in about 2 weeks and immediately begin to spin webs and feed on leaves. Pupation occurs after 4 to 6 weeks of spinning and feeding and can usually be found in leaf litter or just below the surface of the soil. In the South, we are especially lucky - we get at least 2 generations per year!

Control
Control is not necessary; however, you may not be able to tolerate the unsightly mess. If you do decide to take action, mechanical control is best. When you can reach them, prune branches containing webs and destroy them. Chemical control must be done when webs and larvae are small, no later than July, but it is not necessary. If you are lucky, birds and other natural predators may come to your yard and do the job for you!

Just remember – do not eat lunch under the webworm tree…

For more information, go to http://pubs.ext.vt.edu/2808/2808-1013/2808-1013.html

The Age of Exploration and Discovery

During lunchtime the other day, I stopped by our Bayscapes demonstration garden in front of the Museum, to weed the Black-Eyed Susans. Bayscapes features native plants of Virginia that residents can use in their home landscaping which also improve water quality in the James River and Chesapeake Bay. After removing a handful of weeds, I looked up for a moment at the hundreds of flowers moving back and forth to rhythm of the wind, and was immediately transported back in time.
“Put your crayons away, and place your drawings underneath your desks. Now line up. We’re going outside to take a walk.”
It wasn’t recess time, so why were we going outside for a walk, I thought? Behind the school, my classmates and I walked in single file (more or less) following Mrs. Folkes, our first grade teacher, past the swing sets, the seesaws, the monkey bars, and across the dusty, red clay baseball field, and finally down to the edge of an open meadow adjacent to the forest woods.
Stopping at some Black-Eyed Susans hosting a couple of honeybees, Mrs. Folkes said,
“Look. What do you see?”
Without hesitation, Susan said “Two honeybees on a flower.”
“Right” said Mrs. Folkes. “What kind of flowers?”
Billy, who lived on a farm, said “Those are Black-Eyed Susans.”
“Correct. Very good, Billy. Now who can tell me what the bees are doing?”
Even though I didn’t know that particular flower, I knew what honeybees were, and what they were doing on the flowers. My dad had answered the same question when I saw some honeybees on the flowers of bean and tomato plants in his garden just two months earlier. And so, I raised my hand and said “They’re pollinating the flowers so fruits will form.”
“Very good’ said Mrs. Folkes, who reiterated the relationship between bees and flowers to the rest of the class.
As we walked, she stopped every couple of steps or so, and said “this is Queen Anne’s lace, this is an oak tree… this, an elm… here’s a maple… this is moss… look at that six-lined skink… there’s a Monarch butterfly, a bumble bee, carpenter bee, garden spider, broomsedge, and the like. “These grasses were here when the Native Americans lived here. You know, you can still find their arrowheads in the earth.”
Not only did she help us to identify all of these animals and plants, but related one or another to others, and to the history of the area. This was the beginning of a journey of exploration and discovery. Mrs. Folkes was empowering us to see, observe behaviors of insects, and to enjoy the great outdoor classroom. I was seeing and discovering for the first time the great fabric of life. The takeaway message for me that day was that I was an explorer, and could identify new species of plants and animals, things I had never seen before or had not noticed in my previous five years of life. Maybe I had, but they didn’t register with me then. But now, they did (thank you Piaget). And I couldn’t get enough.
Being raised in a traditional Greek family where history and stories are conveyed through either Greek or English language, but often in sentences beginning with Greek or English and ending with the alternate language, small children learn the stories of the Greek gods and goddesses at an early age. And so, at six years old, not really knowing how to distinguish the real world from that of mythology, I thought my first grade teacher, Mrs. Folkes, was actually the Greek goddess, Gaia, who had transformed herself to reveal her divine being. It was magical.

My first grade teacher, goddess or not, did a wonderful thing that day. She made a lifelong impression on me. She showed me how to “see” the natural world, how it was interconnected, and also how to be part of it. And that’s been one of my lifelong endeavors…Helping people not to just look at the world, but to see it as it really is, not what we’ve been told to believe it is, or how we think it is.
And so, I ask you… what, how and where were the beginnings of your age of exploration and discovery?

Eugene G. Maurakis, Ph.D.
Director of Science and Museum Scientist
Science Museum of Virginia

Dive into Deep Sea

By Ben Remo
Science Museum of Virginia intern

Deep under the surface of the world’s oceans is a whole other dimension of life that one has to see to believe. Humans have always been fascinated with the ocean and creatures of the seas. The new IMAX movie, Deep Sea delivers to that curiosity by giving audiences an up-close look at the most bizarre and intriguing sea creatures in existence.


You will be introduced to odd creatures like the mantis shrimp and the Humboldt squid. Usually when you see any ecosystem based documentary, you recognize some of the animals. However, in this film I rarely saw an animal that I recognized. The tiger shark was the only animal in Deep Sea that I could easily identify. Every other animal in the film was new to my eyes. I was fascinated throughout the movie because most of the material was new to me. Your eyes will be glued to the screen as you watch a sun starfish navigate the ocean floor trying to catch sea scallops and you will wonder how the star ever gets to enjoy a solid meal. This and other interesting sea creature stories make the educational film irresistible.

Most IMAX movies can take us to a different place or time. This IMAX movie takes the audience to a different environment all together. Narrated by well known actors Johnny Depp and Kate Winslet, the film showcases beautiful views of the most unique fish in the sea. Depp and Winslet give a play by play on predator and prey relationships as well as how marine life helps one another survive. For example, sea turtles will swim for miles to get a “shell wash” from the reef fish. The fish swim with the turtle eating the algae off its enormous shell. The narrators excel working together to explain the unique relationships and rivalries of the sea.

While there are literally thousands of underwater documentaries out there, and believe me I feel like I have seen them all after my high school oceanography class, this is the most interesting underwater video I have ever seen. It introduces education to entertainment in a way I have never seen before. The clear video and interesting situations will reach out and grab anybody, child or adult, and make them pay attention throughout the 45 minute film.

The star powered narration certainly helps out but the sights are really what set this one apart from the rest. The colorful and at times intense scenes make it hard to pull your eyes away. Throughout the movie, we visit a fried egg jellyfish with a 30 foot tentacle span, an eel with a fishing pole type contraption on its forehead, millions of plankton, and a coral reef built around a sunken ship. This is not just another fish documentary; it takes the audience so much deeper, literally and figuratively.

Words do not do it justice; you really have to see some of these things to believe them.

Beachcombing

Ah, summer at the beach. What is your favorite beach activity? Swimming? Surfing? Volleyball? How about beachcombing? Do you like to collect seashells? Here is a brief guide to shells and other treasures you might discover on Virginia beaches. (To see the real thing, without a trip to the beach, visit the Science Museum’s exhibit, Beach Science: It’s a Shore Thing. The exhibit has labeled examples of most of these shells.)

Whelks are large sea snails; several species are native to Virginia. Knobbed Whelks and Channeled Whelks grow to 9 inches and, like most other whelks, have a right-side opening in their shell. Lightning whelks are similar but have a left-side opening and can grow to 12 inches. Whelks live in the sand in shallow water feeding on clams and other bivalves.

Atlantic Bay Scallop shells come in many colors, are ribbed and have “ears” near the hinge. This scallop lives in shallow waters along the southern Atlantic coast. Unlike other bivalves, scallops lie on the bottom rather than burrowing in the sand.

Angel Wings have a fragile white oblong shell and are found along the Atlantic coast south of Massachusetts. They burrow up to 2 feet in sand or mud and feed on algae through a siphon. Stout Razor Clams look similar but without ribs on the shell.

Arks are boxy bivalves with thick heavy shells that can tolerate rough surf. Several species live in the southern Chesapeake Bay, including the Ponderous Ark and Transverse Ark. Another species, the Blood Ark, is the only clam in the world with red blood.

Northern Quahogs or hard shell clams are usually gray, brown or white, can grow up to 4 inches and may live 30 years. Like Arks, most live in Virginia waters in the southern end of the bay. Native Americans used Quahog shells for wampum.

The Eastern Oyster has a rough gray or white shell and can grow to 4 inches. They attach to one another as they grow, forming dense reefs. Once so numerous that only the working classes would eat them, they are now greatly reduced in numbers.

This odd looking object is a Skate Egg Case. Skates, related to rays, are bottom-dwelling and lay their eggs in the sand. These egg cases, sometimes called “Mermaid’s Purses,” often wash up on Atlantic beaches.

Whelk egg capsules are attached together in a chain of 50-100. One end of the chain is then secured to the sea floor to prevent the eggs from washing ashore where they would dry out. The chain looks a bit like a lei and are sometimes called “Mermaid’s Necklaces.”



For more information, visit http://www.chesapeakebay.net/ and http://www.assateague.net/.  Thanks to both websites for these photos.

The Chesapeake Bay “Ouch” Forecast

Have you met Chrysaora quinquecirrha? If you’ve spent time in the Chesapeake Bay in the summertime, you probably have. His more familiar name is sea nettle, and he is not one of the most pleasant fellows you will ever meet. The sea nettle is a large sea jelly, a semi-transparent bell-shaped invertebrate with long stinging tentacles. Chrysaora quinquecirrha lives along the Atlantic Coast south of Cape Cod. Like many of us, he loves the Chesapeake Bay and its tributaries and can be seen in greater abundance here than anywhere else on the East Coast.
Getting tangled up with a sea nettle is not a fun experience. Those long tentacles contain thousands of microscopic nematocysts; upon contact the nematocysts fire a stinging filament into the victim. Sea nettle stings are not fatal but do cause a burning sensation and a painful rash. People often carry a bottle of meat tenderizer in their beach bags to counteract the sting, but plain vinegar works just as well. Vinegar prevents unfired nematocysts from firing thus preventing further discomfort.
Want to know how to avoid this unpleasant fellow? This summer NOAA is experimenting with sea nettle forecasting. Their website (http://chesapeakebay.noaa.gov/forecasting-sea-nettles) includes a map predicting the probability of encountering one, based primarily on water temperature and salinity. Sea nettles prefer water temperatures between 25° and 30°C (77° - 86°F) and salinity between 10 and 20 parts per thousand. Unfortunately for those of us who love it, the Chesapeake Bay is an ideal sea nettle habitat. So next time you head to the bay or the “Rivah” to swim or water ski, check out NOAA’s sea nettle prediction map. That way, you will know whether or not to pack the meat tenderizer.

THE LOTUS’ MAGIC

By Fernando Luna Vera

Ph.D. Candidate, Chemistry Department, VCU

Science Museum of Virginia Volunteer

On August 16^th 2008 millions of people witnessed one of the greatest achievements in the history of the Olympics games, Michael Phelps winning his eighth gold medal in Beijing. Beyond the incontestable talent of Phelps, this amazing feat was in part possible by the technology he wore. The fabric utilized in his swimsuit emulates a shark’s skin, which minimizes the drag of one’s body in the water. Using this technology, Phelps was able to swim like a shark as if he were hunting his prey.

Bio-inspiration applied to technology development is called Biomimetics. This discipline has shown us that by learning and unraveling nature’s tricks human life can be transformed in many ways, one ruse at a time. One example is the phenomenon of high water repellency (super-hydrophobicity) born by some plant leaves and especially distinguishable in the species Nelumbo lutea better known as the “Lotus,” from where the effect takes its name: The Lotus effect.

When water does not stick to a surface, like on Lotus leaves, the droplets adopt a spherical shape, so it looks like a marble sitting on top of a table. In contrast, when on a surface that is water-friendly (hydrophilic), droplets can spread out and appear flat like a Frisbee. A collateral effect of this is that the sphere-like droplets can roll along the surface instead of slide down on it. This fact creates one of the most appealing features of the Lotus: it can self-clean its own leaves.

This effect is due to water’s high surface tension. Molecules on the droplet’s surface eagerly want to adhere to anything that deter them from being exposed to the water/air interface. Because the Lotus offers a waxy, hydrophobic substrate, the water does not spread out on the leaf. Water has to adopt the shape that allows the smallest air-exposed area: a sphere. Now, since the surface molecules still want to get rid of the overwhelming job of being at edge of the droplet, when the drop rolls down the surface all the tiny particles like soot or pollen found on its path get picked up by it. The water surface then becomes covered with a layer of dirt. This is the way self-cleaning occurs and in the end the leaf and water droplet are happy.

So therefore, self-cleaning is possible when water does not stick to the substrate and retains a spherical configuration. But how does the Lotus achieve this? Using highly sophisticated microscopes, a technique called Scanning Electron Microscopy (SEM), researchers have shown that the Lotus’ surface is not smooth at all and in addition to its waxy layer it possesses a well organized structure. It is widely recognized now by scientists that nearly all super-hydrophobic and self-cleaning leaves consist of an intrinsic hierarchical structure where pillars of micrometric size (just millionths of a meter) arrange to form a forest of columns made of water repellent wax. If Lotus’ surface were waxy, but not smooth, it would repel water; water would not acquire a well-defined sphere-like shape and therefore would not pick up the dirt particles.

This knowledge from the Lotus plant has provided the secret to developing many products available today which produce well structured surfaces (Lotus-like). Some self-cleaning paints, which are used in exterior wall coatings (i.e. Lotusan ®) will self-clean a surface when it rains. Can you image your house having a fresh look just after a summer storm? There are water-repellent fabrics that never get dirty (i.e. Nanotex ®) and are used to manufacture outdoors furniture and clothes that very seldom need to get laundered. General Motors is currently working on developing a Lotus-like metal surface to be incorporated within aircraft-technology that avoids the formation of ice, simply because water won’t stick to this kind of surface. These technologies are not just providing comfort; they help in reducing water consumption too, which in the end turns into environmental gain. The human imagination is unlimited and hopefully new technological applications for the lotus effect are still to come. By the way….have you seen a gecko climbing a wall lately?

References and links:

Bhushan, B., Jung C. Y., Koch K., Phil. Trans. R. Soc. A 2009 367, 1631-1672

http://www.youtube.com/watch?v=MFHcSrNRU5E

Why Hot Sauce is Hot…..

By Fernando Luna Vera

Ph.D. Candidate, Chemistry Department, VCU

Science Museum of Virginia Volunteer

“Can you please pass me the hot sauce?” a friend of mine asked. “This one?” I replied, holding up and showing him a warm spinach dip cup. “No! The spicy one,” he said. As I passed it to him, I mentally wondered an almost childish question, “Why do we call it hot sauce if it is not really hot…nor is it even served warm!” Appreciating and feeling the taste of food involves a complex mechanism that uses the sense of taste, smell and touch. This rise of sensations and perceptions sparked by food requires hundreds of chemical signals and our brain acting as traffic officer to control them.

After you bite a spicy taco your body can recognize that familiar, pungency sensation thanks to a well equipped network of sensors called neurons. Neurons, as do all animal cells, contain a boundary layer called a membrane, where specific receptors are allocated. These receptors are like the geometric figures on the surface of a shape sorter toy which recognizes specific shapes. Certain neurons, called nociceptors, have the specialized job of sensing pain. These kinds of neurons contain a specific receptor for capsaicin, the molecule found in high concentration within chili peppers. One can image then, capsaicin molecules traveling to the tongue and getting caught later by the nociceptors, which immediately after recognizing them, trigger an electrical signal that travels to the brain and makes us aware of the irritating sensation of the hot sauce. That specific capsaicin receptor is called TRPV-1.

But why does our brain read the signal produced by capsaicin as an increment in temperature? An experiment performed in 2000 by scientist of UCLA helped us to better understand this outcome. By using genetic techniques, they “knocked out” the gene that produces the capsaicin receptor (TRPV-1) from a group of mice and compared it with other group that still had the TRPV-1. After exposing the two groups to capsaicin, the one lacking TRPV-1 showed to be insensitive to the irritant substance, as expected. However, surprisingly the same group showed a high insensibility to temperatures above 43ºC, which is when pain is normally sensed. This result implied that the same receptor for the chili peppers irritant molecule is the same receptor for sensing high temperature. So when neurons bind capsaicin, the brain interprets the signal produced as an increase in temperature, like something “hot” is touching your tongue.

Additionally, neurons possess certain receptors called TRM8, which are activated by low temperatures (> 12 ºC). These receptors also happen to be sensitive to menthol, the compound found in high concentration within peppermint and used in products like mouthwashes and toothpaste. By then using the same mechanism for associating capsaicin and hot temperatures, the menthol bond to a TRM8 receptor sends a signal that tricks the brain; therefore, by just the taste of mint, makes you feel cool!

References:

http://student.biology.arizona.edu/honors2007/group12/home12.html

Sven-Eric Jordt, David D McKemy and David Julius, Current Opinion in Neurobiology, 2003, 13:487–492.

M. J. Caterina, A. Lefßer, A. B. Malmberg, W. J. Martin, J. Trafton, K. R. Petersen-Zeitz, M. Koltzenburg, A. I. Basbaum, D. Julius, Science, 2000, 288, 306-313