Fun Facts About Cephalopods

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Octopus are intelligent cephalopods capable of using tools, opening containers, and even play  Photo by: Elias Levy / Flickr

Class Cephalopoda is home to some of the most intelligent and mysterious critters in the sea. Including species of octopus, squid, cuttlefish and nautilus, cephalopods are a type of mollusk that have have lost their hard outer shells. Cephalopods get their name from the Greek word “kephalópoda” meaning “head-feet”, because their arms encircle their heads. Both squid and cuttlefish are known as ten-armed cephalopods because they have eight short arms and two long tentacles (as opposed to eight-armed cephalopods like octopuses).

You surely recognize the sly octopus and the charismatic cuttlefish, but how much do you really know about this class of invertebrates?

Check out these three fun facts:

Squid and cuttlefish may look similar, but don’t be fooled.

For a quick way to tell the two apart, watch them move underwater. Squid are fast-moving predators, where cuttlefish are slower and move by undulating long fins on the sides of their bodies. If that doesn’t work, check out their eyes: squid have round pupils, where cuttlefish pupils are W-shaped. And perhaps the easiest indicator of all? Squid have sleek, torpedo-shaped bodies, compared to the broader, stout body of the cuttlefish.

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Large cuttlefish (from Komodo National Park), while they look similar to Squids, they actually have unique characteristics

Class Cephalopoda is home to one of the most venomous creatures on earth.

The blue-ringed octopus’ venom is 1,000 times more powerful than cyanide, and this golf-ball sized powerhouse packs enough venom to kill 26 humans within minutes. It produces a potent neurotoxin called tetrodotoxin, a potentially deadly substance also found in pufferfish. The venom is produced by symbiotic bacteria in the animal’s salivary glands and is more toxic than that of any land mammals.

So, what happens if you’re bitten by a blue-ringed octopus? First, the venom blocks nerve signals throughout the body, causing muscle numbness. Ultimately, it will cause muscle paralysis—including the muscles needed for humans to breathe, leading to respiratory arrest. If you ever encounter this blue and yellow beauty, back away in a hurry—its bite is usually painless, so you might not know you’ve been bitten until it’s too late.

Octopuses are smarter than you think.

When we think of animal intelligence, it’s vertebrates like dolphins and chimps that get most of the credit. But make no mistake—the octopus holds its own in a battle of wits. Cephalopods have large, condensed brains that have sections entirely dedicated to learning, a trait that is unique among invertebrates. Octopuses’ brilliant problem-solving abilities have been documented time and time again; for example, the infamous Inky the Octopus who slipped through a gap in its tank in a New Zealand aquarium and slid down a 164-foot-long drainpipe into Hawke’s Bay. There’s also evidence octopuses have personalities, and react differently based on how shy, active or emotional they are.

There you have it! Now, go out and impress your friends with your knowledge of these quirky and intriguing invertebrates!

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Stop Insulting Anglerfish Sex

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A deep sea anglerfish called a goosefish and is a member of the Lophiidae family – Sladenia remiger.  Image Credit: NOAA Okeanos Explorer Program, INDEX-SATAL 2010

You may have seen the anglerfish sex video floating around the Internet recently, with titles like “The worst sex in the world is anglerfish sex, and now there’s finally video.” While the video is worth a watch, I think most behavioral ecologist would beg to differ with the main assertion: there’s a lot of bad sex in the animal kingdom.

Why is anglerfish sex supposedly so terrible? A male anglerfish bites a females when he finds her, and then hangs onto her for the rest of his life, essentially turning into a living sac of sperm. But hey, at least he’s alive. In contrast, some species of male widow spiders somersault into the mouths of females as they mate, impaling themselves on their mates’ fangs. It sounds like an evolutionary enigma–why would an organism ever willingly sacrifice itself?–but turns out that that self-sacrifice can increase a male’s chances of fathering the female’s offspring.

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The female bed bug (the larger of the two) is traumatically inseminated by the male (bottom) through her abdomen.

Traumatic insemination” is another great example of not-so-great sex. In this case, bed bug females are the ones getting royally screwed, because traumatic insemination is a nice way of saying males stabbing females through the abdomen with their penises. The sperm then travels through the female’s hemolymph (the insect equivalent of blood), until reaching the ovaries and fertilizing the eggs. Males mate with all available females, because the last male to mate with any given female has the best chance of fathering her offspring. However, females who are subjected to these multiple matings pay a high cost: they have shortened lives and reduced reproductive output, because they have to allocate energy to healing the wounds and dealing with any resulting infections.

People often assume that two organisms mating with one another have the same “goals.” After all, both males and females are presumably invested in having as many healthy offspring as possible. But this is only true up to a certain point. Female widow spiders don’t need males to remain alive after mating, and in fact gain an advantage from eating the male (a ready source of nutrients that will help her with her next clutch!). In contrast, male widow spiders obviously benefit from not being eaten, and instead living to mate another day. Similarly, mating multiple times via traumatic insemination is costly to female bed bugs, who only need enough sperm to fertilize their eggs, while male bedbugs benefit from mating as many times as possible.

These are examples of what biologists call sexual conflict. While the source of conflict is obvious in the widow spiders’ and bed bugs’ cases, sexual conflict occurs anytime male and female genetic interests don’t align. In fact, the only time there is absolutely no potential for conflict is when males and females have exactly the same lifetime reproduction, so that each is equally invested in all of their shared offspring, with no opportunities for having offspring with other partners. In contrast, conflict can arise whenever one sex has the opportunity to improve their chances of having more, or better, offspring. This can happen in many different ways, such as: eating your partner, mating multiple times with the same partner, or even mating with multiple partners.

As a result, sexual conflict isn’t likely in anglerfish, at least those species which only have one mate for their entire lives. Although there are genera of anglerfish where females can have up to 8 males hanging off of her! So there’s potential for sexual conflict there, since the males will presumably compete to father her offspring and could do so in ways that are harmful to the female. However, anglerfish are incredibly hard to study because they generally occur in the deep sea. Frankly, male anglerfish have way more going for them than you might’ve ever thought–keep that in mind next time someone’s making fun of them.

 

Peer edited by Karen Setty.

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Mimicking Electric Eels to Provide Power to Medical Devices

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The electric organ of eels has inspired researchers to develop biocompatible power sources that could be used to power medical devices

While the shock of an electric eel sounds like more of a medical nightmare than a fortunate asset, researchers at the University of Michigan were inspired to simulate the power of these slick creatures in hope of creating power sources for a variety of medical devices. With society’s heavy reliance on technology, it’s not surprising that medical treatments have continued to rely more and more on electrical devices including wearable and implantable sensors, pacemakers, and prosthetics. Just as with any piece of technology, these devices require an electrical power source. However, medical devices face the added requirement of being biocompatible, meaning they must function safely and effectively in the human body. Eel-inspired power sources may achieve this goal of being biocompatible while supplying medical devices with the electricity they need to function.  

The inspirational efficiency with which an eel uses its electrical shock, to help catch prey and protect itself against predators, is the result of natural selection. Electrophorus electricus, know commonly as a knifefish or an electric eel, possesses an electric organ that extends through the back 80% of its body. The organ contains parallel stacks of special cells called electrocytes. When a situation arises that warrants a shock from the eel, its nervous system generates an electric current by activating thousands of electrocytes at the exact same time. As the cells are activated, the positively charged sodium and potassium ions, in and around the cells, move toward the head of the eel. The movement of these ions allows each of the electrocytes to act like small batteries. The activated end that lost the ions has a negative charge, while the opposite side that acquired the sodium and potassium ions carries a positive charge. The battery-like cells can each generate a small, innocuous voltage (less than that of a AAA battery). But when combined, the eel’s shock can be over 600 volts! For reference, a US household outlet supplies 120 volts. While a significant portion of this voltage is lost to the water around the eel, its prey or attacker will still get a nasty shock.

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By developing this work further, researchers hope to successfully use their artificial electric organ to run medical devices like pacemakers

The University of Michigan team has successfully created an artificial electric organ that can potentially be used by humans to power devices. To make the electrical power supply biocompatible, it was necessary to efficiently mimic the features of the eel’s electric organ. This was achieved by preparing hydrogel membranes that could be layered to replicate the structure of the organ. To mimic the movement of ions in and out of the cells, the hydrogels were filled with dissolved table salt, which is made of sodium and chlorine ions. Half of the cells were designed to allow only positively charged sodium ions out and the other half would only allow negatively charged chlorine ions to exit. The gels containing the salt water were alternated on the membrane sheet with gels containing pure water, which allows the sodium and chlorine to move in opposite directions. This flow of ions generates an electric charge with an electrical potential of 110 volts. While this voltage is less than that of the inspirational eel organ, in its current state the artificial organ may be sufficient to power some low-power devices.

Though pleased with the engineering of a potentially biocompatible power source, the researchers acknowledge that there are plenty of opportunities to improve its design. By increasing the efficiency of these artificial organs, researchers believe their utility will increase, as they will become more suitable for use in combination with implantable devices.

Peer edited by Erika Van Goethem.

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The Science Behind Spitting for your At-home Genetic Test

Conjuring up two milliliters of spit after not eating/drinking 30 minutes prior doesn’t sound taxing, but give it a try, and you’ll quickly change your mind. Four years ago, I sat in my kitchen wafting the scent of freshly baked brownies into my face in an attempt to make myself salivate. Voilá! I finally produced enough spit for my 23andMe kit and rewarded myself with a brownie. In 6-8 weeks, I would learn more about my health and ancestry, all thanks to just two milliliters of saliva. Best Christmas gift ever…thanks, mom and dad!

Popularity for these at-home genetic testing kits has soared in recent years. For example, AncestryDNA sold about 1.5 million kits in three days alone last fall. People love buying these DNA kits as a holiday gift, and it’s one of Oprah’s favorite things, so why wouldn’t you want to purchase one? Given the general affordability of these non-invasive tests and the variety of kits to choose from, it’s easy to participate in the fun.

https://commons.wikimedia.org/wiki/File:Tongue1.png & https://pixabay.com/en/genetics-chromosomes-rna-dna-156404

After scientists receive your at-home genetic kit, they isolate cells from your saliva and unravel the chromosomes in your DNA. Then they read your base pairs like a book and check for specific genetic markers that indicate risk of a certain disease. Your ancestry is determined by comparing your genetic markers to a reference database.

I’m amazed that information about my ancestors’ migration pattern is extracted from the same fluid that helped disintegrate the brownie I just ate. In addition to the enzymes that aid in digestion, human saliva contains white blood cells and cells from the inside of your cheeks. These cells are the source of DNA, which is packaged inside your chromosomes. Humans carry two sex chromosomes (XX or XY) and 22 numbered chromosomes (autosomes). Chromosomes are responsible for your inherited traits and your unique genetic blueprint. During a DNA test, scientists unravel your chromosomes and read the letters coding your DNA (base pairs) to check for specific genetic markers.

Companies perform one or multiple kinds of DNA tests, which include mitochondrial DNA (mtDNA), Y-chromosome (Y-DNA), or autosomal DNA. An mtDNA test reveals information about your maternal lineage since only women can pass on mitochondrial DNA. mtDNA codes for 37 out of the 20,000-25,000 protein-coding genes in humans. Y-DNA test is for male participants only and examines the paternal lineage. This DNA accounts for about 50-60 protein-coding genes. Autosomal DNA testing is considered the most comprehensive analysis, since autosomes include the majority of your DNA sequences and the test isn’t limited to a single lineage. However, companies don’t fully sequence your genome because then the at-home kits could no longer be affordable. Instead the tests look at about 1 million out of 3 billion base pairs.

But how reliable are these tests if less than one percent of your DNA is sequenced? When detecting genetic markers that could increase disease risk, these tests are very accurate since scientists are searching for known genes associated with a certain disease. However, the reliability of predicting your ancestry is another story.

Using DNA to determine ethnicity is difficult since ethnicity is not a trait determined by one gene or a combination of genes. Scientists analyze only some of your genome and compare those snippets of DNA to that of people with known origins. For example, Ancestry uses a reference panel that divides the world into 26 genetic regions with an average of 115 samples per region. If your results show that you’re 40% Irish, then that means 40% of your DNA snippets is most similar to a person who is completely Irish. Each company has their own reference database and algorithm to decide your ethnic makeup, so it’s likely that you would receive different results if you sent your DNA to multiple companies.

At-home genetic tests are an exciting and affordable way to explore the possibilities of your genetic makeup and can paint a general picture of your identity. While the specifics of the ethnicity results may be a bit unreliable, at least it’s a good starting point if you’re interested in building your family tree!

Peer edited by Nicole Fleming.

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The Curious Life of Plants: Exploring the Science within the Garden Walls

Cortney CavanaughThe science that plants rely on goes far beyond photosynthesis, the familiar process where plants use sunlight to help make food. In honor of spring’s pending arrival, it’s time to delve into three, unique cases where science influences the plants that color our lives.

The Power of pH

A bitter cup of burnt coffee or a sour lemon wedge can stimulate an intense response from a diner. Just as with humans, plants can respond in curious ways to the acidity (sourness) or basicity (bitterness) of the soil they live in. The acidity and basicity of soil is directly related to its pH. This characteristic is measured in pH units, on a scale that runs from 0 to 14, where 7 is neutral. Values below 7 represent an acidic environment and those above 7 indicate that the soil is basic. While these values can vary based on rainfall and the components of the soil, the typical range falls between 3 and 10, with most plants preferring a pH of 6.5.

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pH indicator paper

In the plant world, soil pH can have huge consequences. The acidic or basic nature of the soil has a strong influence on whether a plant can absorb the nutrients that surround it. Plants require many elements to survive, including nitrogen, calcium, sulfur, and magnesium. While these nutrients are generally abundant in the earth, a plant may be unable to take them in if the pH is not sufficiently acidic or may take in too much if it is too acidic. A plant suffering from an iron deficiency may exhibit a yellow coloring of its leaves. In this case, there is likely enough iron in the soil but the pH is too high (basic) and the iron does not exist in a form that the plant is capable of absorbing. When the pH is too low, plants may begin to absorb too much of their required nutrients, at poisonous levels, or may even begin to absorb some components of soil that are toxic to plants. As with humans, nutrients are necessary for a plant’s survival, but an overdose, or an insufficient intake, can be problematic. In the case of plants, symptoms of this imbalance usually include the discoloration and death of leaves.

It is apparent that maintaining an appropriate soil pH is necessary for a plant’s health, but given the fact that pH levels can vary based on location and yearly rainfall, it is critical to monitor these levels. While there are commercially available digital monitors, one of the easiest methods to check to the pH is through the use of litmus paper. These strips of paper, treated with dyes, change colors based on the pH of the environment. Interestingly, a plant-based version of this litmus paper exists in many gardens. It turns out that the blooms of the very popular Hydrangea macrophylla, or the bigleaf hydrangea, will change colors in response to the pH of the soil. It has long been known that the blooms will turn blue in the presence of acidic soil and shift to a red/pink color when the soil is basic. A variety of home remedies can be used to change the pH of the soil. Adding vinegar or citrus peels to the soil can make the soil acidic and give the blooms a blue color, while powdered limestone results in basic soil and a red hydrangea.

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When the pH of the soil is low, aluminum ions become available, and the hydrangea blooms are blue

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When the pH of the soil is high, and aluminum ions are unavailable, hydrangea blooms display a pink-red color

While many experienced gardeners are familiar with this age-old practice, research over the past decade has begun to reveal that the chemistry behind the colors of the hydrangea goes beyond a simple change in pH and is directly related to the amount of positively charged aluminum ions that the plant can absorb from the soil. When there are no aluminum ions in the hydrangea, the flowers will maintain a red color. This is the result of one type of anthocyanin pigment, a colored molecule, which is present in the bloom. When the pH is lower, and the soil is acidic, the aluminum ions exist in a form that allows them to be absorbed by the roots and carried up to the bloom where they can react with the colored anthocyanin molecule to turn it blue. Basic soil, such as that treated with limestone, causes the aluminum ions to get tied up and prevents them from entering the bloom so the color change doesn’t occur. As a result, the best way to get and maintain blue hydrangeas is to treat the soil with an appropriate amount of aluminum sulfate. This will create an environment that is sufficiently acidic with enough aluminum ions to cause a color change, though this process will take multiple growing seasons. The color change, along with the levels of aluminum ions found within a blue bloom, demonstrate that the color-changing capability of the hydrangea plant is actually a measure of available aluminum ions in the soil, which is directly related to the soil’s pH.

“Life Finds a Way”

When the soil does not provide plants the nutrients they need to survive, certain species will adjust to fit their environment. Commonly, plants will develop specialized leaves that help them to survive despite poor soil quality. One of the liveliest examples of these leaves belong to carnivorous plants, which rely on trap-style leaves to catch their prey and special chemicals, called enzymes, to digest them. The ability to absorb nutrients from prey gives carnivorous plants the chance to exist in wetlands, where the average plant would die after being unable to access essential nutrients from the soil.

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Hair-like triggers sense when prey enters the Venus flytrap

The Venus flytrap is likely the most well known among carnivorous plant species. While most would associate these bug-eating plants with exotic, swampy-jungle locations, their only native habitat is actually southeastern North Carolina and northeastern South Carolina! Their bizarre ability to trap insects and small amphibians comes at a price. A significant amount of energy is required to trap and digest their prey. To prevent unproductive closing events, the Venus flytrap has a method to differentiate between a brush with prey and a false alarm. The trap is lined with hair-like structures that can sense when they are being touched. Research has shown that the plant is able to keep track of how many hair-like sensors have been touched, in a short range of time, and can recognize if there is a struggling bug in its grasp. After two sensors have been touched, a hormone called jasmonic acid is released and an electrical signal is sent through the leaf, causing the trap to snap shut and catch the prey. After the prey has touched five sensors, the plant quickly releases its digestive enzymes, which help the flytrap to absorb the nutrients from its meal. While the small creature likely stands no chance to survive the interaction, the Venus flytrap’s survival is also at risk due the large amount of energy it uses to obtain its meal. Ominously, the flytrap is only capable of closing its trap about four or five times without catching its prey before the plant dies.

Exploring a Friendship at its Roots

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Orchids depend on a relationship with the fungi around its roots for survival

Though they are highly desired for their vibrant blooms, orchids are notorious for being one of the most difficult plants to maintain. While they are often considered one of the easiest domestic plants to kill, orchids are also considered fragile in the wild. Their sensitivity to changes  make orchids excellent indicators of environmental change, but sadly, it has also caused the plants to become endangered. This fragility results from the reliance of orchids on their ecosystem, or the entire community of interacting organisms around them. Research from the Smithsonian Environ­mental Research Center, has shown that orchids rely on the presence of fungi at their roots. The teamwork exhibited by the plant and fungus is an example of a symbiotic relationship in which both members benefit. While the fungi are provided with a moist, nutrient-rich home at the plant’s roots, the orchid receives help from the fungi to take in nourishment when photosynthesis is difficult. Orchids take advantage of the fact that the fungus is able to take the organic matter in soil and break it down into simple molecules, like sugar, that the orchid can then absorb for energy. It has been discovered that all orchids depend on this very relationship. In fact, an orchid will not begin to grow until the fungus enters the plant’s seed, as it is the only source of energy for the developing plant. As the plants mature, they are believed to still rely on this relationship as an alternative food source when sunlight is sparse. There is still a lot to learn about the reliant relationship between orchids and fungi, but what is certainly known about these fragile plants is that their ability to survive is a direct result of a healthy and flourishing ecosystem.  

The life of plants is much more complicated than most people consider. In order to survive, plant species must develop creative ways to adapt to changes in their environment over time. Seeing these ingenious beauties firsthand may be the best way to appreciate them and fortunately, a wide variety of unique plants can be found on display at local spaces including the North Carolina and Duke botanical gardens.

Peer edited by Richard Hodge and Ann Marie Brasacchio.

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Improbable Science: The Ig® Nobel Prize

https://www.improbable.com/ig/ (Permission granted by Marc Abrahams - editer and founder of Ig Nobel Prizes)

“The Stinker”: The official mascot of the Ig Nobel Prizes

When you think of scientific research that is worthy of international recognition, 10 trillion dollars, and a prize handed out by Nobel laureates, you are probably envisioning high-impact research that helped revolutionize its field. Unfortunately, the international recognition is not for the right reasons, the 10 trillion dollars is from Zimbabwe and is worth roughly 30 US dollars, and the Nobel laureates might be laughing as they hand out the prizes. The Ig® Nobel Prize is awarded annually to ten different people in ten different categories. The prize is intended to honor achievements in scientific research that first make people laugh, and then make them think.

Started in 1991 by Marc Abrahams, the Ig® Nobel Prizes are awarded every September at Harvard University. The winners are kept secret until the ceremony, where 1200 spectators cheer on the recipients for their discoveries. Looking back at previous winners can help one get a sense of what kind of research fits the criteria for this prize. The 2017 Ig® Nobel Prize in Medicine focused on using brain-scanning technology (fMRI) to measure how disgusted people are by cheese, while the 2015 Mathematics prize was awarded for mathematically determining whether and how Moulay Ismael the Bloodthirsty, an emperor who reigned Morocco from 1697 to 1727, was able to father 888 children. My personal favorite was the 2005 Chemistry Prize, which attempted to settle the debate of whether people can swim faster in syrup or in water. For more laughs, check out previous winners!

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A live frog levitates in a magnetic field (2000 Ig Nobel Prize in Physics)

With 2017 behind us, we can all look forward to the announcement of the 2018 winners later this year. The event is broadcast live on the internet, with additional coverage provided by NPR’s Science Friday. If you believe your research is worthy of an Ig® Nobel (hopefully it isn’t!), you can send nominations to marc@improbable.com (10-20% of the 9000 nominations every year come from self-nominations). If you happen to be nominated, you will be invited to attend the ceremony, but at your own expense! Don’t feel too self-conscious if you find yourself in this scenario. You can take comfort in knowing that Sir Andre Geim, the winner of the 2000 Physics Ig® Nobel (which he won for using magnets to levitate a frog), also won the Nobel Prize in 2010. Regardless of who wins, it is fun to follow the motto of the Ig® Nobels’, “celebrate the unusual, honor the imaginative, and spur people’s interest in science.”

Peer edited by Bailey DeBarmore.

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Space Travel is Possible with the Sound of Light

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Optical communication devices may be the first step in space travel.

Technology moguls dream of human colonies on other planets. For this dream to become reality, science needs to develop new spacecraft capable of transporting people and cargo to the outer reaches of our galaxy. Another challenge is how to find a route to these other planets.  We can’t just use Google Maps. Space travelers would have to navigate around comets, space debris, or orbiting planets.  Complex models and communications developments would be needed to move through galaxies safely and quickly.

Light-based communication is desirable because it can transmit more data per second while producing significantly less heat. This means that less energy is spent cooling equipment, making the it more efficient to run compared to conventional electron-based communication.

Similar to how electronic devices maneuver electrons through a computer chip, photonic devices maneuver light for optical communication. Normally, a magnetic field is required to produce a change in optical properties necessary for one-way light propagation. However, the size of magnets are too large to be incorporated efficiently into nanoscale devices. To address this problem, University of Illinois researchers created a nanoscale photonic device called an optical isolator, using sound waves instead of magnets for one-way light guidance.

Erika Van Goethem

Cartoon of optical device

The optical isolator device is made from aluminum nitride. A radio frequency driver (RF driver) generates a radio frequency signal that is used to create a sound wave. The RF signal is applied to an IDT, consisting of two interlocking comb-shaped arrays of metallic electrodes that convert electrical signals into surface sound waves. The grating couplers allow the light, generated by a laser, to enter into the device from one direction.  The light travels along the optical waveguides and is transferred from one optical band to another, interacting with the previously converted sound waves. Light is able to pass through the device when the shape of the light wave matches the shape of the sound wave going in the same direction. However, light waves going in the opposite direction of sound waves are absorbed by the device and are unable to pass through, thus maintaining the one-way propagation of light.

This new device allows for a more reliable and sensitive transfer of information that can be used in devices such as atomic clocks and GPS.  Such innovations may be the first step toward developing deep space navigation and travel.

Peer edited by Portia Flowers.

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Cloned Monkeys: Another Human Creation

http://english.cas.cn/head/201801/t20180123_189488.shtml Image credited to Qiang Sun and Mu-ming Poo, Institute of Neuroscience of the Chinese Academy of Sciences

First cloned none-human primates: Zhong Zhong and Hua Hua (Image credited to Qiang Sun and Mu-ming Poo, Institute of Neuroscience of the Chinese Academy of Sciences)

Cloned primates are here! Over three decades have passed since the birth of Dolly, the sheep, scientists have now tackled cloning mammals that are even closer to us on the evolutionary tree: macaque monkeys. What does this mean for a society that witnesses dramatic changes day by day: computers are outperforming doctors in calling out heart abnormalities in patients; 3D-printed organs are bringing us one step closer to tissue restoration; genome sequencing has become an online product easily available for anyone curious about their ancestry, bodybuilding, or just simply wine tastes. Breakthroughs in science and technologies are so prevalent in our life that by now, we probably shouldn’t be surprised by any new discovery. Yet when the two cute, little, cloned monkeys were born, the whole world was, once again, shaken.

Published in Cell on January 24th, 2018, a study from a group of scientists in China reported their methods in generating two non-human primates that are genetically identical. To clone the two identical macaque monkeys, the scientists applied Somatic Cell Nuclear Transfer, the same method that generated Dolly in 1996. The key idea behind cloning is that a new organism, be it sheep or monkey, is generated without sexual reproduction. Asexual reproduction is not as uncommon as one would think, plenty of plants do so. For example, Bryophyllum shed plantlets from the edge of the leaves to produce new plants. Some insects, such as ants and bees, also exploit asexual reproduction to clone a huge working class army. Since asexual reproduction is essentially an organism duplicating itself, the offsprings are all genetically identical. Evolution, however, doesn’t favor asexual reproduction as identical offsprings don’t prevail in a fast changing environment. On the other hand, sexual reproduction combines different sperms and eggs to create diverse offsprings, of which some may survive. To combat challenges from the mother nature, higher organisms, such as mammals, almost exclusively reproduce sexually. This is why a cloned monkey, an anti-evolution human creation, is mind blowing.

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The succulent, genus Kalanchoe, uses asexual reproduction to produce plantlets.

To clone mammals, scientists came up with the idea of transferring the nucleus of a somatic cell to an enucleated egg (an egg that lacks nucleus). Unlike  germ cells (sperm and eggs), somatic cells refer to any cells that don’t get passed onto the next generation. These cells have the full genome of an organism that is split equally in germ cells during sexual reproduction. Carrying half of the genome, sperm and egg need to fuse their genetic materials to make one viable embryo. Technically, the nucleus of a somatic cell holds all the genetic information an organism needs. Thus, by inserting the somatic cell nucleus into an egg, scientists could generate a functional embryo. But why not into a sperm? Evolution has trimmed mammalian sperm tremendously so that it can accomplish its only job better: swim faster to fertilize the egg. As a result, not much other than the sperm’s genetic information is incorporated into the fertilized egg and the embryo relies on the cellular machinery from the egg to finish development. Using this technology, the scientists generated over 300 “fertilized” embryos. Of these embryos, 260 were transferred to 63 surrogate mothers to finish developing. 28 surrogate mothers became pregnant, and from those pregnancies, only 2 healthy monkey babies were born. Although they were carried by different surrogate mothers, every single piece of their genetic code is the same as the the somatic nucleus provider, a real-life demonstration of primate-cloning. Followed by millions of people since their debut to the world, these two macaque superstars are the living samples of a revolutionary breakthrough in our science and technologies.

 

Despite the extremely low success rate, this technology erects another monument in the history of mankind’s creations. Carrying identical genetic information, cloned monkeys like these two can be a very powerful tool in biomedical research and diseases studies. Co-author Mu-ming Poo, director of the Chinese Academy of Sciences’ Institute of Neuroscience in Shanghai, said that these monkeys could be used to study complicated genetic diseases where environmental factors also play a significant role, such as Alzheimer’s and Parkinson’s diseases. While there are ethical concerns on this technology and its easy application to human cloning, it is worth noting that almost all human creations (explosives, GMO food, the internet, etc.) are double-sided swords. It is up to the hand that wields this sword to decide whether to do good or bad. It is wise to be cautious with the development of new technologies, but it’s also important not to constrain our creativity. After all, it is our creative minds that drive us toward creating a better life for everyone.

Peer edited by Cherise Glodowski.

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Why is the Flu such a Big Deal?

With each flu season comes a bombardment of new advertisements reminding people to get a flu vaccine. The vaccine is free to most and widely available, yet almost half of the United States chooses to forgo the vaccine.

When Ebola emerged, there was 24 hour news coverage and widespread panic, but the influenza virus (the flu) feels more familiar and much less fear inducing. This familiarity with the flu makes its threat easy to brush aside. Yet, every flu season is met with stern resolve from the medical community. What’s the big deal with the flu?

What makes the flu such a threat?

Influenza is a globetrotting virus: flu season in the northern hemisphere occurs from October to March and April to September in the southern hemisphere. This seasonality makes the flu a year round battle. The virus also evolves at a blistering pace, making it difficult to handle.

To understand why the flu is able to evolve so rapidly, its structure must be understood.The graphic to the right shows an illustration of the ball-shaped flu virus.

https://www.cdc.gov/flu/images/virus/fluvirus-antigentic-characterization-large.jpg

Illustration of flu structure

On the outside of the ball are molecules that let the virus slip into a person’s cells. These molecules are called hemagglutinin and neuraminidase, simply referred to as HA and NA. HA and NA are also used by our body’s immune system to identify and attack the virus, similar to how a license plate identifies a car.

These HA and NA molecules on the surface can chanAntigenic shift in the fluge through two processes. One such process is like changing one license plate number; this is known as antigenic drift. When the flu makes more of itself inside a person’s cells, the instructions for making the HA and NA molecules slightly change over time due to random mutations. When the instructions change, the way the molecules are constructed also changes. This allows the flu to sneak past our immune systems more easily by mixing up its license plate over time.

Another way the virus can evolve is known as antigenic shift. This type of evolution would be more like the virus license plate changing the state it’s from in addition to a majority of its numbers and letters, making the virus completely unidentifiable to our immune systems. Unlike antigenic drift, antigenic shift requires a few improbable factors to coalesce.  

Antigenic shift happens more regularly in the flu when compared to other viruses.For instance, one type of flu virus is able to jump from birds, to pigs, and then to people without the need for substantial change. This ability to jump between different animals enables antigenic shift to occur.

https://commons.wikimedia.org/wiki/File:AntigenicShift_HiRes_vector.svg

How antigenic shift occur in the flu

This cross species jumping raises the odds of two types of the virus to infect the same animal and then infect the same cell. When both types of the flu virus are in that cell, they mix-and-match parts, as can be seen in the picture to the right. When the new mixed-up flu virus bursts out of the cell, it has completely scrambled it’s HA and NA molecules,generating a new strain of flu.

Antigenic shift is rare, but in the case of the swine flu outbreak in 2009, this mixing-and-matching occured within a pig and gave rise to a new flu virus strain.

This rapid evolution enables many different types of the flu to be circulating at the same time and that they are all constantly changing. This persistent evolution results in the previous year’s flu vaccine losing efficacy against the current viruses in circulation. This is why new flu vaccines are needed yearly. Sometimes the flu changes and becomes particularly tough to prevent as was the case with swine flu. At its peak, the swine flu was classified by the World Health Organization (WHO) as a class 6 pandemic, which refers  to how far it had spread rather than its severity. Swine flu was able to easily infect people, fortunately it was not deadly. The constant concern of what the next flu mutation may hold keeps public health officials vigilant.

Why is there a flu season?

A paper by Eric Lofgren and colleagues from Tufts University grapples with the question “Why does a flu season happen?”. The authors highlight several prevailing theories that are believed to contribute to the ebb and flow of the flu.

One contributing factor to the existence of flu seasons is our reliance on air travel. When flu season in the Australia is coming to an end in September, an infected person can fly to Canada and infect several people there, kickstarting the flu season in Canada. This raises the question: why is flu season tied with winter?

The authors touch on this question. During the winter months, people tend to gather in close proximity allowing the flu access to many potential targets and limiting the distance the virus need to cover before infect another person. This gathering in confined areas likely contributes to the spread of flu during the winter, but another theory proposed in this paper is less obvious and centers around the impact of indoor heating.

Heating and recirculating dry air in homes and workplaces creates an ideal environment for viruses. The air is circulated throughout  a building without removing the virus particles from the air, improving the chances of the virus infecting someone. The flu virus is so miniscule that air filters are unable to effectively remove it from the air. The authors come to the conclusion that the seasonality of the flu is dependent on many factors and no single cause explains the complete picture.

What are people doing to fight the flu?

The flu is a global fight, fortunately the WHO tracks the active versions of the flu across the world. This monitoring system relies on coordination from physicians worldwide. When a patient with the flu visits a health clinic, a medical provider, performs a panel of tests to detect the type and subtype of flu present. This data is then submitted to the WHO flu database, which is publicly accessible.

This worldwide collaboration and data is invaluable to the WHO; it allows for flu tracking and informed decision making when formulating a vaccine. Factor in the rapidly evolving nature of the flu and making an effective vaccine seems like a monumental task. Yet, because of this worldwide collaboration twice a year, the WHO is able to issue changes to the formulation of the vaccine as an effort to best defend people from the flu that year.

Peer edited by Rachel Cherney and Blaide Woodburn.

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How Evolution Gave Us Dragons

https://www.flickr.com/photos/x1brett/5953249239

Hiccup and his friendly dragon, Toothless, from How to Train Your Dragon. Credit: Brett Jordan

Whether our favorite characters are trying to train them, ride them, or simply escape from them, there is no denying the prevalence of dragons in popular culture. Dragon myths have existed for centuries in every civilization. In medieval Europe, uncharted parts of maps were supposedly marked with “Here be dragons” to designate danger and the unknown. In contrast, Chinese culture sees dragons as symbols of wisdom and benevolence. It is remarkable that such similar looking mythical creatures popped up separately in various cultures – and there may be an evolutionary explanation.

Dragons are depicted as large, reptilian-like creatures that can sometimes fly and breath fire. But why reptiles and why do they have to be so huge? It has often been speculated that some of the first discoveries of dinosaur or whales bones helped spark dragon mythology. People who discovered these huge bones, which resembled nothing they were familiar with, could have come up with a mythical creature like the dragon to explain them. However, it may not have been the curious mind that spawned dragons, but the fearful one.

In the book An Instinct for Dragons, anthropologist David E. Jones makes the case that a primal fear of predators, such as big cats and snakes, generated the dragon myth. Studies of Vervet monkeys demonstrate that they are especially fearful of three particular predators – lions, eagles, and snakes – and Vervet monkeys have specific cries they make when they spot these predators. Jones argues that this primal fear could have been passed along to humans through evolution. It is not hard to imagine our fearful ancestors combining the body of a snake with something as ferocious as a lion, and tacking on the ability to fly like an eagle, to get a dragon.

https://pixabay.com/en/animal-beast-creature-dragon-2029670/ (left) https://commons.wikimedia.org/wiki/File:Chinese_black_dragon.svg (right)

A primal fear of snakes, lions, and eagles may have inspired the creation of dragons in Western (left) and Eastern culture (right).

The hypothesis proposed by Jones is an interesting one, but has received criticism. It is nearly impossible to test and as powerful as evolution is, there is also the possibility that the myth was passed from culture to culture through storytelling. With cultures being so isolated for much of history, it would have been difficult for that to occur, but not impossible. And while their huge size would make it impossible for dragons to fly, it is not impossible to imagine that dragon myths will continue to mesmerize people for centuries to come.

Peer edited by Tom Gilliss.

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