Tag: Biology

5 Cool Things DNA Testing Can Do

Genes are the foundation of our physiology. They contain the code that determines what we look like and how our bodies function.

Biologist James Watson and physicist Francis Crick realized our DNA molecules form a three-dimensional double helix in 1953. But DNA research dates back to the late 1860s, according to Nature Education.

Friedrich Miescher was the first to identify “nucleic acid” in our white blood cells; his 1869 finding was later named deoxyribonucleic acid, or DNA.




Others later defined the components that make up DNA molecules, identified RNA (ribonucleic acid, the other type of nucleic acid found in all cells along with DNA) and determined that although DNA differs in each species, it always maintains certain properties.

Those findings led to Watson and Crick’s conclusion, which paved the way for decades of DNA discoveries.

Today we use DNA tests to tell us about all kinds of things. Here are five cool things DNA testing can do:

Map your family tree

A DNA test could give you thousands of new relatives (although if they’re anything like ours, we’re not sure why you’d want them).

There are websites that offers to compare your DNA to those they already have on record in hopes of connecting you to unknown branches of your family tree.They can also tell you your genetic ethnicity.

Solve ancient mysteries

No one knew where Richard III, one of the most famous kings of England, was buried until his remains were discovered in a parking lot in Leicester.

The remains showed evidence of battle wounds and scoliosis, but scientists weren’t sure the skeleton was Richard III’s until DNA extracted from the bones was matched to Michael Ibsen, a direct descendant of the king’s sister.

It wasn’t the first time ancient remains had been identified using DNA. If it’s stored in a cold, dry, dark place, DNA can last for thousands of years.

In 2009, a DNA analysis of some bone fragments showed two of Czar Nicholas II’s children were killed along with the rest of the family during the Russian Revolution, despite speculation they could have escaped.

Scientists have even extracted DNA from Neanderthals, who went extinct about 30,000 years ago, in hopes of gaining insight into the evolution of humans.

Distinguish your mutt

“Where does Buddy get his curly tail from? Why does he love digging holes in the backyard? Could I be doing more to make him happier and healthier? Your dog may not be able to tell you the answers — but his DNA can,” claims one dog DNA site.

You’ll probably never figure out why Buddy loves to eat your favorite Italian pumps but you can figure out where he comes from. The website will test your mutt’s DNA against that of more than 190 breeds to determine his genetic background.

“But why?” cat lovers may be asking. “When you understand your dog’s natural tendencies, you can tailor a training, exercise and nutrition program to his needs,” the site explains.

Predict the future

Using blood from the mother and saliva from the father, scientists can now determine whether a fetus has any chromosomal abnormalities that could cause a genetic disorder.

For example, DNA testing can reveal if an unborn baby will have trisomy 21, or Down syndrome.

Researchers are beginning to expand the field of prenatal genetic testing even further, using it to identify potential developmental delays and intellectual disabilities such as autism.

Genetic testing can also reveal risk factors you may have inherited from your parents, such as a high risk for breast or colon cancer.

While this genetic risk factor does not guarantee you will get the disease, it does increase your chances; knowing about the risk may help you take preventive steps.

Help you lose weight

A growing body of research suggests that our ability to lose weight — or gain 10 pounds by simply looking at a piece of chocolate — is shaped in large part by our genes.

Scientists have identified several gene variants that may predispose us, and our children, to obesity. Rodent studies have also shown that up to 80% of body fat is regulated by our genes, according to TIME.

That said, we wouldn’t search for a customized DNA Diet just yet. While there is a genetic component to obesity, our understanding of it is limited, says CNN diet and fitness expert Dr. Melina Jampolis.

Researchers are still trying to figure out how genetics, nutrition and exercise are related so we can help people lose weight and keep it off.

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Some Ants Are Not As Industrious As You Think. Meet The Lazy Ants!

LAZY ANT

Ants are thought to be industrious and efficient, with everyone in the colony working really hard. However, that might not be as true as once thought.

Some species of ants were actually found to have what’s called lazy ants in their colonies and scientists are baffled!

In 2015, a group of ants called Temnothorax rugatulus are labelled as lazy. This species of ants build their colonies under rocks in the lands of western North America.




Daniel Charbonneau and Anna Dornhaus at the University of Arizona think that these lazy ants are old. They noticed that these lazy ants seem to do nothing–nothing at all.

However, when observed keenly, they found that these “lazy” ants aren’t actually as useless as they thought; their behaviors are just different from other ants.

These ants walk more slowly, are isolated in colony interaction networks and have the smallest behavioural repertoires,” he says.

These lazy ants aren’t necessarily old as they’ve once assumed, they just seem to be immature workers.

LAZY ANT

Their appearances are different too, with plumper bodies and usually having egg cells inside them. Researchers hypothesized that this might their way of storing food–putting it inside them to share with other ants later.

Inactive workers storing food for the colony,” he says. It could also be that the eggs inside them are the food for their brothers and sisters, since there are other species of ants that lay unfertilized edible eggs. However, what this laziness for is still uncertain.

LAZY ANT

As the authors state, there very likely is not just one reason for these inactive ants,” Erik Frank at the University of Würzburg in Germany says. “They probably have various benefits for the colony and reasons for their inactivity.

The researchers are now looking into other ant species to see if lazy ants exist on other types. “The next thing is really starting to look at the function and explanation for inactivity across species to see if there’s some main mechanism which facilitates inactivity,” Charbonneau says.

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Can Eating Too Much Make Your Stomach Burst?

I ate so much I’m about to burst!

Someone at your Thanksgiving table likely said this, after you’ve all stuffed your faces with turkey, mashed potatoes, sweet potatoes and the rest.

But how much would you have to eat in order for your stomach to actually burst? Is that even possible?

Interestingly enough, you can rupture your stomach if you eat too much,” says Dr. Rachel Vreeman, co-author of “Don’t Cross Your Eyes … They’ll Get Stuck That Way!” and assistant professor of pediatrics at Indiana University School of Medicine.

It is possible, but it’s very, very rare.

A handful of reports over the years document the tales of people who literally ate themselves to death, or at least came dangerously close.

Japanese doctors wrote in a 2003 case report that they believed it was a 49-year-old man’s “excessive over-eating” that caused his stomach to rupture, killing him.




And this 1991 case report describes a similar “spontaneous rupture” in an adult’s stomach “after overindulgence in food and drink.

Normally, your stomach can hold about one or one-and-a-half liters, Vreeman says — this is the point you may reach if you overdo it tomorrow, when you feel full to the point of nausea.

Pathologists’ reports seem to suggest the stomach is able to do OK handling up to about three liters, but most cases of rupture seem to occur when a person has attempted to stuff their stomach with about five liters of food or fluid.

It takes a certain amount of misguided determination to manage to override your natural gag reflex and continue to eat.

Which is, not surprisingly, reports of ruptured stomachs caused by overeating are most common in people with some sort of disordered eating, or limited mental capacity, Vreeman says.

Speaking of strong stomachs, you’d best have one in order to read this next paragraph. If vomiting isn’t happening, all that food and fluid still has to go somewhere.

The increasing volume of stuff in the gut puts pressure on the stomach’s walls, so much so that the tissue weakens and tears, sending the stomach contents into the body and causing infection and pain, Vreeman says.

Surgical intervention is necessary to repair a ruptured stomach and save the patient’s life.

In particular, she says, anorexics or bulimics may be at risk. In fact, Cedars-Sinai, the non-profit hospital in Los Angeles, actually lists this as a “symptom” of bulimia.

In rare cases, a person may eat so much during a binge that the stomach bursts or the esophagus tears. This can be life-threatening.

Other reported cases of spontaneous stomach rupture happen in individuals with Prader-Willi syndrome, a congenital disease that is characterized by, among other things, a kind of disordered eating.

An “intense craving for food,” resulting in “uncontrollable weight gain and morbid obesity.” according to the National Institutes of Health.

In a 2007 study examining the deaths of 152 individuals with the condition, 3 percent of those deaths were the result of gastric rupture and necrosis.

The takeaway here: This really happens, sometimes! Also: This is probably not going to happen to you.

Even if you’re starting to feel a bit sick or tired and overwhelmed from eating so much at Thanksgiving, you’re still far, far away from the scenario where you’re going to make your stomach actually explode,” Vreeman assures.

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Fire Ants Can Build Roiling Ant Towers To Get Around

fire ants

Ants don’t just build complicated nests. They’ll use their own bodies to make things, too. Researchers at Georgia Tech University are studying how the insects link together to make ant rafts and ant bridges.

Now, they’ve accidentally found that fire ants can also get around by using themselves to constantly build and rebuild a moving tower.




Researchers filmed fire ants climbing on top of each other and left the cameras rolling. When they watched the sped-up footage, they found the ant structure sinks under its own weight, so the insects constantly renewed the tower until they went where they wanted to go.

They fed ants radioactive food and watched them build towers in an X-ray machine so they could watch the interior of the tower sink as it grew. Ants that got pushed to the bottom eventually disengaged and started climbing again.

Behavior like this serves a purpose: Fire ants in their natural habitat in Brazil have to deal with frequent flooding. Rafts and towers are a way to escape water and relocate to a new home.

fire ants

It’s worked so well it’s kept ants alive for millions of years all over the world — and in Georgia Tech’s buildings, where they’ve been known to escape labs and set up camps under staffers’ desks.

nd designs based in biology could make our own construction more efficient. Scientists think ant building-techniques like this replenishing trick could be useful for self-assembling robots in the future.

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Power Of The web: Methods Of How Spiders Catch Their Prey

spider web

Spun from silk, with the strength of steel but with extraordinary elasticity, a spider’s web has long been regarded as one of Mother Nature’s most amazing feats.

Now scientists at Oxford University have revealed another unique quality – webs actively spring towards prey thanks to electrically conductive glue spread across their surface.

Researchers discovered that the electrical properties of a glue that coats spider webs causes them to reach out to grab all charged particles, from pollen and pollutants to flying insects.




The study, published in Naturwissenschaften journal, shows how a quirk of physics causes webs to move towards all airborne objects, regardless of whether they are positively or negatively charged.

This explains why webs are able to spring towards prey and how they collect small airborne particles so efficiently. Spider webs could, according to researchers, be used for environmental monitoring as they actively filter airborne pollutants with the same accuracy as expensive industrial sensors.

spider web

“Electrical attraction drags airborne pollutants including aerosols and pesticides to the webs, so you could harvest and test webs to monitor pollution levels – for example, to check for pesticides that might be harming bee populations,” said Professor Fritz Vollrath of Oxford University’s department of zoology, who led the study.

“What’s fascinating is that you can detect some airborne chemicals just by looking at the shape of the webs. Many spiders clear particles from their webs by eating them, including chemicals that are electrically drawn to the web.”

In tests spiders are known to create different qualities of web depending on their drug consumption, Professor Vollrath said.

spider web

The researchers showed that the webs also cause local distortions in the Earth’s electric field since they behave like conducting discs.

Many insects are able to detect small electrical disturbances, including bees, that can sense the electric fields of different flowers and other bees.

Electrical disturbances caused by spider webs are extremely short-ranged, so it is not yet clear whether insects would be able to sense them before the web snaps out to grab them.

spider web

Professor Vollrath added that spider webs make use of the static charge developed by moving insects to “actively catch prey”.

The latest revelation will add to the fascination with spiders’ webs, the structures of which are already under investigation for potential applications in industry, including in bullet-proof vests and even in artificial tendons.

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Zoologists Explained Why The Ostrich Is The Only Living Animal With Four Kneecaps

According to experts, the unusual structure of the legs allows the bird to accelerate quickly.

Ostrich is one of the most interesting and unusual birds in the modern world. He can’t fly but runs very fast and has the largest size among the brethren.

In addition, the ostrich is the only living creature on Earth with four knees.




After a series of studies, scientists have created a computer model of the leg of the ostrich. This allowed them to understand why the “extra” body parts of this bird has not disappeared with evolution.

As it turned out, four knee ostriches need for rapid response to possible danger. When a member of the species feels the approach of the enemy, he may suddenly break away from their homes, developing a decent speed.

In this case the leg bone of an ostrich face enormous pressure, while a special mechanism reduces the load. That is part of it and are knees.

Zoologists said that while not believe in his theory 100%. Researchers simply have nothing to compare the results of their work, since 1884, on the Ground there are no other organisms with four knees, in addition to ostriches.

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The Prehistoric Puzzle Of How Plesiosaurs Swam Through The Oceans

Among the stranger creatures to roam the earth during the time of the dinosaurs was not a dinosaur at all, but a marine reptile — the plesiosaur.

This odd predator navigated Mesozoic Era waters with four flippers — two in the front and two in the back — a design unlike anything seen in modern-day swimmers.

How the plesiosaur actually used its limbs to swim has remained something of a mystery.

But in a study in the journal PLOS Computational Biology, a group of scientists has used computer modeling to pin down what those strokes might have looked like — and it turns out that they probably looked a lot like a penguin’s.




Plesiosaurs were a diverse group of swimming reptiles that thrived for 135 million years, from the Early Jurassic to the Late Cretaceous period (when they were wiped out by the same asteroid that took out the dinosaurs).

Some had long necks, others had short stubby ones, but all of them had this four-flippered body plan, where the animals’ legs had evolved into two pairs of wing-like appendages — “a unique adaptation in the animal Kingdom,” the study authors wrote.

Although plesiosaurs were a key component of Mesozoic marine ecosystems, there are no extant ‘four-winged’ analogues to provide insights into their behavior or ecology, and their locomotion has remained a topic of debate since the first complete plesiosaur skeleton was described in 1824,” the authors wrote.

Without any clear modern comparisons, how theirs flippers worked together has stumped scientists.

Some have argued that the plesiosaur had a rowing stroke, using its fins like boat oars; others argued for a “flight stroke,” rather like those of penguins and turtles, or a modified flight stroke like the ones sea lions use.

The extinct animals’ swimming motion has been equally up for grabs: Some have posited synchronous motion, with all four flippers moving in the same direction at the same time.

Others have favored semi-synchronous or asynchronous motion, where the forelimbs and hindlimbs move out-of-phase relative to each other.

Researchers haven’t even been able to agree on whether it was the forelimbs or the hindlimbs producing most of the animal’s thrust.

Scientists have tried all kinds of ways to model the animals’ swimming behavior, from using experimental robots to testing out human swimmers using paddles.

These studies, although informative, are limited because they do not deal with accurate representations of the plesiosaur form,” the study authors wrote.

There is therefore still no consensus on how plesiosaurs swam, especially how they moved all four limbs relative to each other.”

To get a better handle on plesiosaur physiology, researchers from Georgia Tech decided to build a computer model — far more accurate than, say, a human with some paddles.

They based theirs on Meyerasaurus victor, a Lower Jurassic plesiosaur from what is now Germany that would have stretched about 11 feet (relatively small by plesiosaur standards).

This model also allowed researchers to test thousands of simulations to try to determine which combinations of movement allowed the animal to move most effectively through the water.

In the end, the scientists found that the plesiosaur was swimming mostly with its forelimbs; surprisingly, the hindlimbs didn’t generate much thrust and likely were used for balance and steering.

Within the biologically possible range of limb motion, the simulated plesiosaur swims primarily with its forelimbs using an unmodified underwater flight stroke, essentially the same as turtles and penguins,” the study authors wrote.

Now that the scientists have developed a working model of this plesiosaur, they can use it to further probe exactly how the hindlimbs were used — and to explore the motion of other extinct swimming animals.

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These Gourmet Snakes Prefer To Eat Snails

Showin’ off those baby blues.

There’s something strange about the five newly discovered snakes in Ecuador: Unlike most snakes that dine on rats, lizards and other small animals, these slithery reptiles eat snails.

And that’s pretty much all these snakes can eat. There are now 75 known species of snail-eaters, according to a new study on the reptiles.

The jaws of these snakes are modified so much that they cannot eat anything that isn’t a snail or a slug,” said lead study author Alejandro Arteaga, a doctoral student with the American Museum of National History in New York.

Sometimes, you can see [one] hanging from vegetation with a snail in its mouth,” he said.

Indeed, snail-eating snakes have a jawline that has evolved to slurp the snail right out of its shell — but the snakes do this without suction (in other words, it’s not the way we slurp oysters from a shell).

To extract their escargot, the snakes push their lower jaws into the shell and grasp the flesh of the slimy critter with their curved teeth.




Once the snakes have a firm grasp, they pull the prey out without crushing the shell — a process that usually takes a few minutes.

This snail-slurping “is an interesting adaptation,” Arteaga told Live Science. Because not many snakes feed on these snails, the predators don’t have much competition for food, he added.

But the snakes have other things to worry about.

Arteaga and his team are proposing that three of the five species should be listed as “vulnerable” under the International Union for Conservation of Nature’s Red List of Threatened Species and that one should be listed as endangered.

Four of them are facing the possibility of extinction. Only one is safe,” Arteaga said.

The reason? A lack of cover for the snakes to hide in.

In western Ecuador, “only 2 percent of the original vegetation cover remains,” Arteaga said. The rest of the forest cover and vegetation was destroyed by activities like logging and clearing land for cattle farming and human settlement.

Ultimately, there’s “not really much forest left,” Arteaga said, and that’s not good for the snakes, who need forest cover, vegetation, moisture and nearby streams to survive. “They cannot survive in open cattle ranch [or] grassland.”

Arteaga and his team recently held an auction for the “naming rights” to the snakes.

With the money from that auction, the researchers will purchase a 178-acre (72 hectares) plot of currently unprotected land where some of these snakes live and thereby expand the Buenaventura Reserve in Ecuador.

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The Space Station Is Becoming A Spy Satellite For Wildlife

In 1250, the prior of a Cistercian Abbey reputedly tied a note to a leg of a barn swallow, which read: “Oh swallow, where do you live in winter?” The next spring, he got a response: “In Asia, in the home of Petrus.

This perhaps apocryphal story marks one of the first known instances of someone tagging an animal to track its movements.

Thanks to many such endeavors, we now know that every year, barn swallows migrate between their breeding grounds in the northern hemisphere to wintering grounds throughout the tropics and the south.

In 1912, one intrepid individual that was ringed in England turned up 7,500 miles away in South Africa.

But swallows are the exception rather than the rule. The journeys of most migratory animals, especially smaller species, are a mystery.




Flocks, herds, and shoals are constantly crisscrossing the globe, but despite the intense surveillance of our planet, we often have no idea what paths they take.

They leave in one place and we don’t know what happens to them until they show up in another place,” says Meg Crofoot from the University of California, Davis.

This ignorance makes it hard to save threatened species: what works in one part of the world may be completely undone as animals travel to another. It also jeopardizes our own health.

Where are the birds that harbor avian flu? Where do the bats that carry Ebola go? What about the red-billed quelea, a small finch that flocks in millions and devours crops with locust-like voraciousness?

Since the 1960s, scientists have tried to answer questions like these by tagging animals with radio transmitters. At first, they followed the signals with clunky hand-held antennae.

Later, they loaded receivers onto satellites, allowing them to track animals over long distances and rough terrain.

But even after decades of innovation, satellite telemetry tags are still expensive, slow, and clunky. The smallest weighs around 10 grams and would overburden any animal lighter than 240 grams.

That rules out three quarters of birds and mammals. There are much lighter data-loggers around but they’re light because they don’t transmit any data—so you have to recapture whatever animal you’ve tagged to find out where it has been.

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5 Hard-Shelled Facts About Horseshoe Crabs

The plodding sea creatures have weird blood, weirder swimming habits, and a secret weapon that’s probably saved your life.

1. HORSESHOE CRABS ARE INCREDIBLY OLD.

Discovered in 2008, the 25 millimeter-wide Lunataspis aurora crawled over Manitoba 445 million years ago. This makes it the world’s oldest-known horseshoe crab.

Four species are with us today, all of which closely resemble their long-extinct ancestors.

Supposedly frozen in time, horseshoe crabs are often hailed as “living fossils” by the media.




Yet, appearances can be misleading. Evolution didn’t really leave these invertebrates behind. They’ve transformed quite a bit over the past half-billion years.

For instance, some prehistoric species had limbs that split out into two branches, but today’s specimens have only one.

2. THEY’RE NOT CRABS.

In fact, they aren’t even crustaceans. Unlike real crabs and their kin, horseshoe “crabs” lack antennae.

So, where do the strange ocean-dwellers belong on the arthropod family tree? Biologists classify them as chelicerates, a subphylum that also includes arachnids.

Members possess two main body segments and a pair of unique, pincer-like feeding appendages called chelicerae.

3. EACH ONE HAS A HUGE ARRAY OF SIGHT ORGANS.

Large compound eyes rest on the sides of their shells. Come mating season, these bean-shaped units help amorous crabs locate a partner. Behind each one, there’s a small, primitive photoreceptor called a lateral eye.

Towards the front of the shell are two tiny median eyes and a single endoparietal eye. On its underside, a horseshoe has two “ventral eyes,” which presumably help it navigate while swimming.

4. BABIES CAN SWIM UPSIDE DOWN.

Walking around on the ocean floor is generally how horseshoe crabs get from point A to point B.

Nevertheless, young ones will often flip over and start propelling themselves through the water, using their gills as extra paddles. With age, they do this less frequently.

5. THE SPIKED TAIL HAS SEVERAL USES.

Stinging isn’t one of them, despite what many falsely believe. Among its uses are assuming rudder duties and helping the arthropod right itself after getting stuck on its back.

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