To celebrate the end of the year, I compiled a list of The Scorpion and the Frog's most popular posts of 2015. If you missed them, check them out here:
#5. Gut Feelings explains new research that shows that the microorganisms living in our guts can affect our behavior in mysterious ways.
#4. In Vole Pee: An Epiphany, Nate Kueffer talks about how birds of prey use ultraviolet vision to see pee-trails of their prey.
#3. Prepare to be amazed! Enjoy The Weirdest Animals on Earth: 12 Amazing Facts About Octopuses.
#2. Rachael Pahl tells us about some crazy bug sex in The Bed Bug’s Piercing Penis.
#1. In The Beginnings of Jurassic Park: Dinosaur Blood Discovered?, Sam Vold contemplates the real science behind Jurassic Park.
There have been some fascinating animal stories by many great science writers. Here's to many more stories in 2016! Happy New Year!
Tuesday, December 29, 2015
Monday, December 21, 2015
Caught in My Web: All About Dogs
Image by Luc Viatour at Wikimedia. |
1. Nina Golgowski at HuffPost Science explains research that shows that dogs give treats to their doggy friends, but not to doggy strangers.
2. Rafael Mantesso's wife left him and took everything but the dog and the empty white apartment. Rafael found inspiration in his predicament and created some of the most wonderful photos ever! Check them out here.
3. Let puppies teach you about complexity theory in this TED talk by Nicolas Perony.
4. Virginia Hughes at National Geographic shares research that shows that dog brains process voice information similarly to our own.
5. And just for fun, here is Bella the dog singing “Jingle Bells”:
Monday, December 14, 2015
Why Are Cats Scared of Cucumbers?
Have you seen the video of cats’ terrified responses to cucumbers? No?! Then check this out:
This hilarious video has led many people to try this on their own cats… to varying degrees of success. And it has led to some curious questions: Why are these cats so terrified of a cucumber? And why isn’t my cat?
The fear of something specific (like a cucumber) can either be innate (as in, you’re born with it) or learned. For many animal species, it would make sense to be born with a natural fear of something that can kill you the first time you encounter it, like a steep drop, being submerged under water, or a venomous snake. Some of these things can be so dangerous that an animal with a fear of anything that even resembles it may have a higher chance of surviving long enough to produce its own fearful babies some day. So maybe these cats have an innate fear of snakes that has caused them to respond in this hilarious way to anything that resembles a snake… like a cucumber?
But if cats have an innate fear of snakes, why don’t they all respond to cucumbers this way?
Sometimes fears appear to be innate, when they are actually learned. For example, in 2009, researchers Judy DeLoache and Vanessa LoBue at the University of Virginia explored whether the fear of snakes is innate in human babies with a series of three experiments.
In the first experiment, Judy and Vanessa showed 9- and 10-month old babies silent films of snakes and other animals and they measured how long the babies looked at each type of film. Presumably, a baby will be more vigilant of and spend more time looking at something they are scared of. They found that the babies responded exactly the same towards the snake films than to the films of other animals.
Next, the experimenters showed the babies the films of either a snake or another animal again. However, this time they played the audio of a person sounding either happy or frightened along with the video. The babies looked at the non-snake animal videos the same amount regardless of whether the audio sounded happy or scared. However, the babies looked at the snake videos longer if the audio sounded scared than if the audio sounded happy.
In the third experiment, the experimenters repeated this pairing of audio with visuals, but this time they used still pictures of snakes and non-snake animals instead of videos. This time, the babies did not react differently to the snake or non-snake animal pictures depending on if the audio sounded happy or scared.
This shows that, at least for people, we don’t have an innate fear of snakes, but we do have an innate tendency to develop a fear of snakes if we are exposed to the right combination of hearing someone being afraid and seeing a moving snake. In other words, some fears are more contagious than others. And this isn’t just true for people: a study of rhesus monkeys found that baby monkeys raised by parents that were afraid of snakes only developed a fear of snakes themselves if they observed their parents acting fearful in the presence of a real or toy snake. So perhaps, the cats in this cucumber video saw or heard someone being fearful of something cucumber-like (or snake-like) when they were young... Or maybe they were just surprised by something sneaking up on them while they were eating.
In any case, don’t be too bummed if this hasn’t worked on your cat… Maybe try it on your friends instead!
Want to know more? Check these out:
DeLoache, J., & LoBue, V. (2009). The narrow fellow in the grass: human infants associate snakes and fear Developmental Science, 12 (1), 201-207 DOI: 10.1111/j.1467-7687.2008.00753.x
Mineka, S., Davidson, M., Cook, M., & Keir, R. (1984). Observational conditioning of snake fear in rhesus monkeys. Journal of Abnormal Psychology, 93 (4), 355-372 DOI: 10.1037/0021-843X.93.4.355
This hilarious video has led many people to try this on their own cats… to varying degrees of success. And it has led to some curious questions: Why are these cats so terrified of a cucumber? And why isn’t my cat?
The fear of something specific (like a cucumber) can either be innate (as in, you’re born with it) or learned. For many animal species, it would make sense to be born with a natural fear of something that can kill you the first time you encounter it, like a steep drop, being submerged under water, or a venomous snake. Some of these things can be so dangerous that an animal with a fear of anything that even resembles it may have a higher chance of surviving long enough to produce its own fearful babies some day. So maybe these cats have an innate fear of snakes that has caused them to respond in this hilarious way to anything that resembles a snake… like a cucumber?
But if cats have an innate fear of snakes, why don’t they all respond to cucumbers this way?
Sometimes fears appear to be innate, when they are actually learned. For example, in 2009, researchers Judy DeLoache and Vanessa LoBue at the University of Virginia explored whether the fear of snakes is innate in human babies with a series of three experiments.
In the first experiment, Judy and Vanessa showed 9- and 10-month old babies silent films of snakes and other animals and they measured how long the babies looked at each type of film. Presumably, a baby will be more vigilant of and spend more time looking at something they are scared of. They found that the babies responded exactly the same towards the snake films than to the films of other animals.
Next, the experimenters showed the babies the films of either a snake or another animal again. However, this time they played the audio of a person sounding either happy or frightened along with the video. The babies looked at the non-snake animal videos the same amount regardless of whether the audio sounded happy or scared. However, the babies looked at the snake videos longer if the audio sounded scared than if the audio sounded happy.
In the third experiment, the experimenters repeated this pairing of audio with visuals, but this time they used still pictures of snakes and non-snake animals instead of videos. This time, the babies did not react differently to the snake or non-snake animal pictures depending on if the audio sounded happy or scared.
This shows that, at least for people, we don’t have an innate fear of snakes, but we do have an innate tendency to develop a fear of snakes if we are exposed to the right combination of hearing someone being afraid and seeing a moving snake. In other words, some fears are more contagious than others. And this isn’t just true for people: a study of rhesus monkeys found that baby monkeys raised by parents that were afraid of snakes only developed a fear of snakes themselves if they observed their parents acting fearful in the presence of a real or toy snake. So perhaps, the cats in this cucumber video saw or heard someone being fearful of something cucumber-like (or snake-like) when they were young... Or maybe they were just surprised by something sneaking up on them while they were eating.
In any case, don’t be too bummed if this hasn’t worked on your cat… Maybe try it on your friends instead!
Want to know more? Check these out:
DeLoache, J., & LoBue, V. (2009). The narrow fellow in the grass: human infants associate snakes and fear Developmental Science, 12 (1), 201-207 DOI: 10.1111/j.1467-7687.2008.00753.x
Mineka, S., Davidson, M., Cook, M., & Keir, R. (1984). Observational conditioning of snake fear in rhesus monkeys. Journal of Abnormal Psychology, 93 (4), 355-372 DOI: 10.1037/0021-843X.93.4.355
Monday, December 7, 2015
Are GMO Fish Safe for the Environment?
Photo of an Atlantic salmon by Hans-Petter Fjeld, licensed under the Creative Commons Attribution ShareAlike 3.0 License and available at Wikimedia Commons. |
Today at Accumulating Glitches, I talk about genetic engineering, GMOs, and what scientists think about whether AquAdvantage Salmon pose a risk to our environment. Check out the whole article here.
Monday, November 30, 2015
This Animal Looks Like a Penis With Teeth... But It's Even Stranger Than That
This is a naked mole rat.
Naked mole rats are rodents that live in underground tunnels under East African savannas and grasslands. There's nothing all that strange about that... but how they have adapted to this lifestyle is unique... and, quite frankly, amazing.
For one thing, to cope with the low oxygen levels of the subterranean environment, naked mole rats have very low metabolisms and breathing rates. One of the biggest uses of metabolic engines in mammals is to produce our own body heat. These little guys have cut this big expenditure by being what may be the only ectothermic mammals on the planet. Ectotherms are animals like most fish, amphibians and reptiles that get most of their body heat from their environment, rather than making it themselves. Because naked mole rats want to exchange heat with their environment, they want to eliminate insulation... giving them their hairless and fatless bodies. Now when they bask in the sun at their tunnel entrances or huddle with their family they can take in all that warmth without anything getting in the way.
There are some benefits to having low metabolisms and not using much oxygen: Naked mole rats live for nearly 30 years (compared to 1-3 years in regular rats). Oxygen creates free radicals, highly reactive chemicals that cause damage to DNA, leading to a wide range of diseases. Naked mole rats don't just use less oxygen, but they have special proteins that are resistant to these damaging chemicals. They also produce a specialized super-sugar that has essentially eliminated cancer in this long-living species. What's more, these elderly rodents have managed to avoid dementia and osteoporosis, traits we hope to learn more about through ongoing research.
Naked mole rats have also developed some unique sensory traits. Living with your entire extended family in underground burrows means that you live in high levels of carbon dioxide and walls saturated in pee. These little guys don't even have any body hair to protect their pink skin from all that burning ammonia. Their solution: get rid of pain. These guys have no pain receptors for noxious chemicals like acids or capsaicin (the stuff that makes hot peppers hot). Furthermore, they are lacking a specific neurotransmitter, called substance P, that other mammals use to send many pain signals. Since naked mole rats have less need for sensation in their skin, they have developed brains that have repurposed about 30% of the sematosensory cortex (the part of the brain that interprets touch sensations) to their digging teeth!
Perhaps the strangest quality of all for these animals is their behavior. Naked mole rats are one of only two known mammals that are eusocial (the other being the Damaraland mole rat). Eusociality is a social organization common among bees, wasps, ants and termites, in which the colony has castes that include queens, workers and soldiers. Among naked mole rats, there is a single queen in the colony that mates with a few dominant males; workers that dig the tunnels, gather food, and care for the young; and soldiers that protect the colony from predators. Workers and soldiers are all reproductively sterile with undeveloped gonads and low hormone levels. However, if the queen dies, one of the non-reproducing females will go through puberty and take on her role as the new queen.
Now that you know that naked mole rats are so much more than just a "freaky thing", enjoy this naked mole rat rap (or maybe even a whole episode of Disney's Kim Possible, which features Rufus, the naked mole rat):
Yes, this is arguably the freakiest-looking animal on Earth. Photo by Roman Klementschitz at Wikimedia Commons. |
Naked mole rats are rodents that live in underground tunnels under East African savannas and grasslands. There's nothing all that strange about that... but how they have adapted to this lifestyle is unique... and, quite frankly, amazing.
For one thing, to cope with the low oxygen levels of the subterranean environment, naked mole rats have very low metabolisms and breathing rates. One of the biggest uses of metabolic engines in mammals is to produce our own body heat. These little guys have cut this big expenditure by being what may be the only ectothermic mammals on the planet. Ectotherms are animals like most fish, amphibians and reptiles that get most of their body heat from their environment, rather than making it themselves. Because naked mole rats want to exchange heat with their environment, they want to eliminate insulation... giving them their hairless and fatless bodies. Now when they bask in the sun at their tunnel entrances or huddle with their family they can take in all that warmth without anything getting in the way.
There are some benefits to having low metabolisms and not using much oxygen: Naked mole rats live for nearly 30 years (compared to 1-3 years in regular rats). Oxygen creates free radicals, highly reactive chemicals that cause damage to DNA, leading to a wide range of diseases. Naked mole rats don't just use less oxygen, but they have special proteins that are resistant to these damaging chemicals. They also produce a specialized super-sugar that has essentially eliminated cancer in this long-living species. What's more, these elderly rodents have managed to avoid dementia and osteoporosis, traits we hope to learn more about through ongoing research.
Naked mole rats have also developed some unique sensory traits. Living with your entire extended family in underground burrows means that you live in high levels of carbon dioxide and walls saturated in pee. These little guys don't even have any body hair to protect their pink skin from all that burning ammonia. Their solution: get rid of pain. These guys have no pain receptors for noxious chemicals like acids or capsaicin (the stuff that makes hot peppers hot). Furthermore, they are lacking a specific neurotransmitter, called substance P, that other mammals use to send many pain signals. Since naked mole rats have less need for sensation in their skin, they have developed brains that have repurposed about 30% of the sematosensory cortex (the part of the brain that interprets touch sensations) to their digging teeth!
Perhaps the strangest quality of all for these animals is their behavior. Naked mole rats are one of only two known mammals that are eusocial (the other being the Damaraland mole rat). Eusociality is a social organization common among bees, wasps, ants and termites, in which the colony has castes that include queens, workers and soldiers. Among naked mole rats, there is a single queen in the colony that mates with a few dominant males; workers that dig the tunnels, gather food, and care for the young; and soldiers that protect the colony from predators. Workers and soldiers are all reproductively sterile with undeveloped gonads and low hormone levels. However, if the queen dies, one of the non-reproducing females will go through puberty and take on her role as the new queen.
Now that you know that naked mole rats are so much more than just a "freaky thing", enjoy this naked mole rat rap (or maybe even a whole episode of Disney's Kim Possible, which features Rufus, the naked mole rat):
Monday, November 23, 2015
The Science Life 2
The life of a scientist is increasingly stressful. Sometimes it helps to relieve stress in song:
Vote for your favorite in the comments section below. If you would like to see more music videos on the life of a scientist, check out The Science Life. And if you feel so inspired, make a video of your own, upload it on YouTube and send me a link to include in a future post!
“Bad Habits” by Nathaniel Krefman (Parody of “Magic” by B.o.B. featuring Rivers Cuomo):
“Eight Days a Week” by the UC-Berkeley Molecular and Cell Biology Department (Parody of “Eight Days a Week” by The Beatles):
“The Tale of a Post Doc” by James Clark at Aerospace Medicine at King’s College London (Parody of "Bohemian Rhapsody" by Queen):
Vote for your favorite in the comments section below. If you would like to see more music videos on the life of a scientist, check out The Science Life. And if you feel so inspired, make a video of your own, upload it on YouTube and send me a link to include in a future post!
Monday, November 16, 2015
Animal Mass Suicide and the Lemming Conspiracy
Ticked off Norway lemming doesn't like gossip! Photo from Wikimedia Commons by Frode Inge Helland |
But it is a LIE.
And who, you may ask, would tell us such a horrendous fabrication? Walt Disney! Well, technically not Walt Disney himself…
Today I am revisiting an article I wrote in the early days of The Scorpion and the Frog, explaining animal mass suicide and the role of Disney in creating one of the greatest animal behavior hoaxes of all time. You can read the article in it's entirety here.
Monday, November 9, 2015
Caught in My Web: The Intelligence and Creativity of Crows, Octopuses, Monkeys, Fish and Dogs
Image by Luc Viatour at Wikimedia. |
1. Joshua Klein talks about crow intelligence and their potential for training in this fun TED talk.
2. Jason Goldman at io9 explains an amazing discovery that Atlantic cod can also innovate to solve problems.
3. Sarah Williams at Science explains research out of Harvard that shows that untrained rhesus monkeys can do math and we can use this to learn about how we think.
4. A veined octopus shows off his imagination as he creates a “hiding” place:
5. And last, but not least, three shelter dogs were taught to drive! Here are the results:
Monday, November 2, 2015
Body Armor is Not Always for Protection
When we see an animal covered in scales and plates, we assume that it has this armor to protect itself from predators. It seems obvious, which is probably why scientists had not really tested it… until now. And they found that it is not necessarily true.
Today at Accumulating Glitches, I talk about new research on the functions of plates and scales in cordylid lizards. Check it out here.
And to learn more, check this out:
Broeckhoven, C., Diedericks, G. and le Fras Mouton, P. What doesn’t kill you might make you stronger: functional basis for variation in body armour, Journal of Animal Ecology, 84, 1213–1221 (2015). DOI: 10.1111/1365-2656.12414.
An armadillo girdled lizard has some impressive body armor, but does it do what we think it does? Image by Handre Basson at Wikimedia Commons. |
And to learn more, check this out:
Broeckhoven, C., Diedericks, G. and le Fras Mouton, P. What doesn’t kill you might make you stronger: functional basis for variation in body armour, Journal of Animal Ecology, 84, 1213–1221 (2015). DOI: 10.1111/1365-2656.12414.
Monday, October 26, 2015
4 Real-Life Monsters
During the Halloween season, we find ourselves surrounded by monsters in movies, stores and decorations. We laugh at the ridiculousness of it all, oblivious to the fact that there are true monsters on our planet today! Mind you, these are not monsters in that they are evil, but they do have many of the same abilities and inclinations of our own mythical werewolves, vampires, zombies and shape-shifters.
Barau’s petrel is a migrating sea bird that is most active during nights with a full moon. Researchers tied bio-loggers on the birds’ feet to track their activity levels and found that under the full moon, the birds spent nearly 80% of these moonlit nights in flight! It is thought that since these birds migrate longitudinally (parallel with the equator), they can’t use changes in day length as a cue to synchronize their breeding, so they use the phases of the moon instead.
Three different bat species feed solely on blood: the common vampire bat, the hairy-legged vampire bat and the white-winged vampire bat. Feeding on blood is not uncommon – The actual term for it is hematophagy, and it is common in insects (think of those pesky mosquitos) and leeches. Although we don’t commonly think of it this way, blood is a body tissue and, like meat, it is rich in protein and calories. The reason it has not become a more popular food source among mammals is probably because it is so watered down (literally) compared to meat, that it can’t provide enough nutrition to sustain a large warm-bodied mammal. This is where our little vampire bat friends come in… small, stealthy, and with specialized saliva that prevents their victims’ blood from clotting, these guys are able to take advantage of this abundant resource, drinking up to half of their body weight in blood every night.
Scientists have recently discovered some strange honey bees: They mindlessly leave their hives in the middle of the night and fly in circles, often towards lights. It turns out that these honey bees are being parasitized by a species of phorid fly called the zombie fly. Female phorid flies lay their eggs inside the abdomens of honey bees, where the eggs hatch into larvae. The larvae feed on the insides of their bee hosts until they are mature enough to leave through the poor bee’s neck (the honey bee is generally dead by this time). Once out, the zombie flies develop into adults so they can breed and start the cycle anew with a new bee host. This phenomenon is still in the early stages of discovery, so if you would like to get involved in this project by watching honey bees in your area, check out ZomBee Watch, a citizen science project to track this zombie infestation.
The mimic octopus is a small harmless octopus that lives on the exposed shallow sandy bottoms of river mouths. To avoid its many predators it has developed an amazing strategy: it pretends to be something else, morphing its body into new shapes, like the shape of a deadly lion-fish, a poisonous flatfish, a venomous banded sea-snake, or any number of other animals that live in the area. Not only does the mimic octopus change its shape, it also changes its behavior to match its “costume” to convincingly fool predators. Most cephalopods, which include octopuses, are well-known for their ability to change the color, pattern and texture of their skin to blend in with rocks, coral and plants. Furthermore, octopuses do not have rigid skeletal elements, which allows their bodies great flexibility in the forms they imitate. But this ability to change both physical appearance and behavior to switch back and forth among imitations of multiple species is unique to this astounding shape shifter.
Werewolf birds:
A Barau's petrel. Photo by SEOR available at Wikimedia Commons. |
Vampire bats:
Three different bat species feed solely on blood: the common vampire bat, the hairy-legged vampire bat and the white-winged vampire bat. Feeding on blood is not uncommon – The actual term for it is hematophagy, and it is common in insects (think of those pesky mosquitos) and leeches. Although we don’t commonly think of it this way, blood is a body tissue and, like meat, it is rich in protein and calories. The reason it has not become a more popular food source among mammals is probably because it is so watered down (literally) compared to meat, that it can’t provide enough nutrition to sustain a large warm-bodied mammal. This is where our little vampire bat friends come in… small, stealthy, and with specialized saliva that prevents their victims’ blood from clotting, these guys are able to take advantage of this abundant resource, drinking up to half of their body weight in blood every night.
Zombees:
Scientists have recently discovered some strange honey bees: They mindlessly leave their hives in the middle of the night and fly in circles, often towards lights. It turns out that these honey bees are being parasitized by a species of phorid fly called the zombie fly. Female phorid flies lay their eggs inside the abdomens of honey bees, where the eggs hatch into larvae. The larvae feed on the insides of their bee hosts until they are mature enough to leave through the poor bee’s neck (the honey bee is generally dead by this time). Once out, the zombie flies develop into adults so they can breed and start the cycle anew with a new bee host. This phenomenon is still in the early stages of discovery, so if you would like to get involved in this project by watching honey bees in your area, check out ZomBee Watch, a citizen science project to track this zombie infestation.
Shape shifters:
The mimic octopus is a small harmless octopus that lives on the exposed shallow sandy bottoms of river mouths. To avoid its many predators it has developed an amazing strategy: it pretends to be something else, morphing its body into new shapes, like the shape of a deadly lion-fish, a poisonous flatfish, a venomous banded sea-snake, or any number of other animals that live in the area. Not only does the mimic octopus change its shape, it also changes its behavior to match its “costume” to convincingly fool predators. Most cephalopods, which include octopuses, are well-known for their ability to change the color, pattern and texture of their skin to blend in with rocks, coral and plants. Furthermore, octopuses do not have rigid skeletal elements, which allows their bodies great flexibility in the forms they imitate. But this ability to change both physical appearance and behavior to switch back and forth among imitations of multiple species is unique to this astounding shape shifter.
Monday, October 19, 2015
Vampires!
Photo by Alejandro Lunadei at Wikimedia. |
Vampires feed on the blood of their victims in order to sustain their own lives. This phenomenon, called hematophagy, is more common than typically occurs to us at first. Just take mosquitoes and ticks as examples. Once we’ve opened our minds to the idea of bloodthirsty arthropods, we quickly think of many more: bedbugs, sandflies, blackflies, tsetse flies, assassin bugs, lice, mites, and fleas. In fact, nearly 14,000 arthropod species are hematophages. We can expand our thoughts now to worms (like leeches), fish (such as lampreys and candirús), some mammals (vampire bats), and even some birds (vampire finches, oxpeckers, and hood mockingbirds). We’ve been surrounded by vampires our whole lives, we just never sat up to take notice!
Hematophagous animals are not as scary as mythical vampires, in part because they don’t suck their victims dry – they just take a small blood meal to sustain their tiny bodies. Hematophagy is not, in itself, lethal. However, the process of exposing and taking the blood of many individuals transmits many deadly diseases, like malaria, rabies, dengue fever, West Nile virus, bubonic plague, encephalitis, and typhus.
Because blood feeders do not kill their meals, feeding can be even more dangerous for them than for traditional predators. As a result, many hematophagous animals have developed a similar toolkit. Many have mouthparts that are specialized to work as a needle or a razor and biochemicals in their saliva that work as anticoagulants and pain killers. Their primary skill, however, is their stealth: they can sneak up on you, eat their meal, and be home for bed before you even notice the itch.
Although a few species, like assassin bugs and vampire bats, are obligatory hematophages (only eat blood), most hematophages eat other foods as well. Somehow, Dracula is not quite so intimidating when you imagine him drinking his morning fruit juice, like many mosquitoes do.
Why drink blood in the first place? Blood is a body tissue like any other, and it contains a lot of protein and a variety of sugars, fats and minerals, just like meat. However, blood is mostly water, which means that a blood meal contains less protein and calories than the same weight of meat. Because you need to consume so much more to get enough protein and calories out of a meal, large animals and animals that generate their own body heat can't usually rely on blood meals alone. So much for human-like vampires that only live off the blood of their victims.
A deadly vampire spreading malaria. Photo by the CDC available at Wikimedia. |
So true vampires are everywhere, but they are small, take small blood meals, don't generally kill their hosts, and often use blood to supplement their other meals. Not so scary any more, are they? ...Although, about 3.2 billion people (about half the world's population) are at risk of contracting the deadly disease, malaria, from these bloodsuckers... so maybe you aren't scared enough. Bwaa-haha!
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Monday, October 12, 2015
How Fashion Destroyed My Best Friend (A Guest Post)
By Sarah Johanson
Man’s Best Friend is a title that has been passed onto our four-legged, drooling counterpart. Dogs have been at man’s side for a number of years showing us his dedication and protection. In the 19th Century, humans started breeding dogs as a hobby. Today, humans have created more than 400 breeds, with less than 200 being recognized by the American Kennel Club, and all can be traced back to the same canid ancestors similar to the gray wolf. As humans selectively bred dogs based on their physical appearances to make a fashion statement, beneath the skin genetic and physiological changes where happening that would have a far harsher consequence to dogs’ health. One such breed is the English Bulldog.
All dog breeds have what are known as breed standards that are set by the Kennel Club or the American Kennel Club. These standards dictate what the breed should look like physically. At first, dogs were bred on a guideline of form follows function. Bulldogs were bred to help butchers control bulls in the slaughter yard. They had long snouts with strong jaws, necks and shoulder muscles while also being tall, allowing them to be quick and agile. However, during the fashion era of dog breeding in the 19th century, breeding became more of a hobby for physical appeal rather than for the dog to have a purpose… which brought us the bulldog we see today.
Over time, the bulldogs’ upper jaws and snouts have been shortened by a significant amount, giving them those mushed short faces. They were bred this way because people thought they looked cute. This shortening is caused by a genetic mutation which causes a developmental defect during bone formation. It’s thought the defect became prevalent due to severe inbreeding. This shortening of the upper jaw has led to there not being enough space in bulldogs’ mouths. Their tongues and palates are often compressed, with the teeth on their lower jaws protruding out in odd directions as their teeth don’t fit, leading to problems with eating and chewing food.
Bulldog nostrils have also been compressed to the point that they can barely breathe. If a human were to breathe like the bulldog, it would be like breathing through a straw. Having a small airway has led the bulldog to become easily overheated and exercise intolerant. To cool down most dogs pant, using water as a tool to take heat away with it as it evaporates. Due to the soft palates not being able to fit in the dogs’ mouths and the narrowing of their throats, panting interferes with breathing. This leads to the production of foam, which blocks the airways even more, sometimes causing suffocation.
Bulldogs are also unable to mate on their own or give birth successfully. Due to their short, stocky bodies, very wide shoulders and narrow pelvises, most males cannot breed with the female on their own. The female either needs to be attached to a breeding stand which gives her body support in order to bear the male’s weight or she needs to be artificially inseminated. Furthermore, a natural birth is almost impossible as the puppies’ heads are too large to fit through the breed’s narrow pelvis to leave the body. This condition, known as dystocia, causes over 80% of bulldog births to be performed via caesarian section. Almost all bulldog births need some kind of human assistance; otherwise they would risk the life of the mother and her unborn puppies.
These are only some of the physical challenges bulldogs face, not to mention all of the medical problems that could follow. It has been the selective breeding done by breeders and the breed standards set that have turned this dog from the power it once was to the mess that it is today. The bulldog became a fashion statement and although he continues to want to please his human counterpart, his body cannot keep up with his desire.
Work Cited:
Baldwin Bulldog. “Bulldogs Overheat.” Baldwin Bulldogs, 10 Dec. 2014. Web. 23 Feb. 2015.
Denizet-Lewis, Benoit. “Can the Bulldog Be Saved?”nytimes.com. The New York Times, 22 Nov. 2011. Web. 5 Feb. 2015.
Dog Breed Health. “Bulldog (English Bulldog).” Dog Breed Health, n.d. Web. 6 Feb. 2015.
Dogtime. “A Brief History of Breeding.” Dogtime, 30 May. 2009. Web. 5 Feb. 2015.
Kalmanash, Angela. “The Physiology and Morphology of a Breed Standard” DogChannel. DogChannel, 9 June. 2014. Web. 5 Feb. 2015.
Thomson, Keith Stewart. “Marginalia: The Fall and Rise of the English Bulldog” American Scientist. 84(1996): 220-223. Web. 7 Feb. 2015.
“Bulldog Portrait Frank”. Image by Pharaoh Hound at Wikimedia. |
Man’s Best Friend is a title that has been passed onto our four-legged, drooling counterpart. Dogs have been at man’s side for a number of years showing us his dedication and protection. In the 19th Century, humans started breeding dogs as a hobby. Today, humans have created more than 400 breeds, with less than 200 being recognized by the American Kennel Club, and all can be traced back to the same canid ancestors similar to the gray wolf. As humans selectively bred dogs based on their physical appearances to make a fashion statement, beneath the skin genetic and physiological changes where happening that would have a far harsher consequence to dogs’ health. One such breed is the English Bulldog.
All dog breeds have what are known as breed standards that are set by the Kennel Club or the American Kennel Club. These standards dictate what the breed should look like physically. At first, dogs were bred on a guideline of form follows function. Bulldogs were bred to help butchers control bulls in the slaughter yard. They had long snouts with strong jaws, necks and shoulder muscles while also being tall, allowing them to be quick and agile. However, during the fashion era of dog breeding in the 19th century, breeding became more of a hobby for physical appeal rather than for the dog to have a purpose… which brought us the bulldog we see today.
Head Comparison of a Bulldog (bottom) and that of a Labrador Retriever (above). Bulldog image “Camilla, the english bulldog,” by Trevomeisel at Wikimedia. Labrador image and edits done by Sarah Johanson. |
Bulldog nostrils have also been compressed to the point that they can barely breathe. If a human were to breathe like the bulldog, it would be like breathing through a straw. Having a small airway has led the bulldog to become easily overheated and exercise intolerant. To cool down most dogs pant, using water as a tool to take heat away with it as it evaporates. Due to the soft palates not being able to fit in the dogs’ mouths and the narrowing of their throats, panting interferes with breathing. This leads to the production of foam, which blocks the airways even more, sometimes causing suffocation.
Bulldogs are also unable to mate on their own or give birth successfully. Due to their short, stocky bodies, very wide shoulders and narrow pelvises, most males cannot breed with the female on their own. The female either needs to be attached to a breeding stand which gives her body support in order to bear the male’s weight or she needs to be artificially inseminated. Furthermore, a natural birth is almost impossible as the puppies’ heads are too large to fit through the breed’s narrow pelvis to leave the body. This condition, known as dystocia, causes over 80% of bulldog births to be performed via caesarian section. Almost all bulldog births need some kind of human assistance; otherwise they would risk the life of the mother and her unborn puppies.
Diagram of bulldog body shape demonstrating how the “box head” of the breed cannot fit through the pelvic bone (triangle) during birth due to size and shape. Image created by Sarah Johanson. |
These are only some of the physical challenges bulldogs face, not to mention all of the medical problems that could follow. It has been the selective breeding done by breeders and the breed standards set that have turned this dog from the power it once was to the mess that it is today. The bulldog became a fashion statement and although he continues to want to please his human counterpart, his body cannot keep up with his desire.
Work Cited:
Baldwin Bulldog. “Bulldogs Overheat.” Baldwin Bulldogs, 10 Dec. 2014. Web. 23 Feb. 2015.
Denizet-Lewis, Benoit. “Can the Bulldog Be Saved?”nytimes.com. The New York Times, 22 Nov. 2011. Web. 5 Feb. 2015.
Dog Breed Health. “Bulldog (English Bulldog).” Dog Breed Health, n.d. Web. 6 Feb. 2015.
Dogtime. “A Brief History of Breeding.” Dogtime, 30 May. 2009. Web. 5 Feb. 2015.
Kalmanash, Angela. “The Physiology and Morphology of a Breed Standard” DogChannel. DogChannel, 9 June. 2014. Web. 5 Feb. 2015.
Thomson, Keith Stewart. “Marginalia: The Fall and Rise of the English Bulldog” American Scientist. 84(1996): 220-223. Web. 7 Feb. 2015.
Monday, October 5, 2015
How Fungus Makes Ant Zombies
The parasitic fungus, Ophiocordyceps unilateralis sensu latu (O. unilateralis, for short), infects the brains of Carpenter ants, turning them into zombies that live and die for the sole purpose of helping the fungus thrive and reproduce. Under the influence of the fungus, zombie Carpenter ants leave their nests at an odd yet specific time, move randomly and convulsively, and climb up the north side of a plant to almost exactly 25 cm, where they bite the leaf vein. Once they bite the leaf, the muscles of their mandibles (mouth parts) deteriorate, causing lockjaw and fixing the ant victim in place while its legs kick and twitch. After a few hours, the movement stops as the fungus kills the ant, continues to grow throughout the victim's head, and then sprouts out of the back of the head. The fungus anchors itself to the plant and releases antimicrobial chemicals to protect itself and grows fruiting bodies from the ant's head to release its spores, spawning the next generation of fungus. O. unilateralis has been known to infect and wipe out entire Carpenter ant colonies, leaving dense aerial graveyards of ant carcasses in its wake.
Today at Accumulating Glitches, I talk about new research that has used genetic techniques to determine how this parasitic fungus takes over the minds of its ant victims. Check it out here.
And to learn more, check this out:
de Bekker, C., Ohm, R.A., Loreto, R.G., Sebastian, A., Albert, I., Merrow, M., Brachmann, A. and Hughes, D.P. Gene expression during zombie ant biting behavior reflects the complexity underlying fungal parasitic behavioral manipulation, BMC Genomics, 16:620, 1-23 (2015). DOI 10.1186/s12864-015-1812-x.
Today at Accumulating Glitches, I talk about new research that has used genetic techniques to determine how this parasitic fungus takes over the minds of its ant victims. Check it out here.
And to learn more, check this out:
de Bekker, C., Ohm, R.A., Loreto, R.G., Sebastian, A., Albert, I., Merrow, M., Brachmann, A. and Hughes, D.P. Gene expression during zombie ant biting behavior reflects the complexity underlying fungal parasitic behavioral manipulation, BMC Genomics, 16:620, 1-23 (2015). DOI 10.1186/s12864-015-1812-x.
Monday, September 28, 2015
What Animals Contagiously Yawn?
Does this sight make you want to yawn?
Do you think it would make other animals want to yawn? Many animals yawn spontaneously, but yawning in response to sensing or thinking about someone else doing it may be a completely different thing. Contagious yawning requires a sense of social connection and emotional empathy that not all species share. So far, scientists have found experimental evidence of contagious yawning in humans, chimpanzees, domestic dogs (who interestingly yawn when people yawn, but not when other dogs do), and an abnormally yawny genetic line of rats. However, there have also been reports of bonobos, baboons, wolves, and budgerigars (small social parrots, also called budgies or parakeets) yawning contagiously in the wild, so this phenomenon may be more widespread than previously thought.
Andrew Gallup, Lexington Swartwood, Janine Militello and Serena Sackett from the State University of New York at Oneonta set out to experimentally test if budgerigars do in fact yawn contagiously. In one experiment, the researchers placed pairs of birds in separate adjacent cages with perches facing one another. They video recorded the birds both with an opaque barrier between them and without the opaque barrier. The researchers found that when the birds could see one another they were three times more likely to yawn within 5 minutes of the other bird yawning, although there was no difference in the overall number of spontaneous yawns.
Next, the researchers decided to test if budgerigars contagiously yawn in response to videos of another budgerigar yawning. They played 10-minute videos of either yawning or non-yawning budgerigars on a laptop facing the birdcage. And who would have guessed that the budgies yawned twice as much in response to the yawning video than to the non-yawning video, showing that even our pet birds can get something out of watching TV!
Budgerigars are now the first non-mammalian species to display contagious yawning. Contagious yawning is not just interesting in itself, but it may also indicate a sense of empathy. Although we often limit our thinking of empathy to our own species, it makes sense to find empathetic behavior among social species like budgerigars. Now if we could just find more of it amongst our own species…
Want to know more? Check this out:
Gallup, A., Swartwood, L., Militello, J., & Sackett, S. (2015). Experimental evidence of contagious yawning in budgerigars (Melopsittacus undulatus) Animal Cognition, 18 (5), 1051-1058 DOI: 10.1007/s10071-015-0873-1
A yawning Japanese macaque by Daisuke Tashiro at Wikimedia Commons. |
Andrew Gallup, Lexington Swartwood, Janine Militello and Serena Sackett from the State University of New York at Oneonta set out to experimentally test if budgerigars do in fact yawn contagiously. In one experiment, the researchers placed pairs of birds in separate adjacent cages with perches facing one another. They video recorded the birds both with an opaque barrier between them and without the opaque barrier. The researchers found that when the birds could see one another they were three times more likely to yawn within 5 minutes of the other bird yawning, although there was no difference in the overall number of spontaneous yawns.
Images of a yawning budgie from Gallup et al., 2015. |
Budgerigars are now the first non-mammalian species to display contagious yawning. Contagious yawning is not just interesting in itself, but it may also indicate a sense of empathy. Although we often limit our thinking of empathy to our own species, it makes sense to find empathetic behavior among social species like budgerigars. Now if we could just find more of it amongst our own species…
Want to know more? Check this out:
Gallup, A., Swartwood, L., Militello, J., & Sackett, S. (2015). Experimental evidence of contagious yawning in budgerigars (Melopsittacus undulatus) Animal Cognition, 18 (5), 1051-1058 DOI: 10.1007/s10071-015-0873-1
Monday, September 21, 2015
Science Beat: Round 5
Science concepts can be daunting at times… and sometimes they just make more sense with a beat. Try these science music videos on for size:
Vote for your favorite in the comments section below and check out other sciency song battles at Science Beat, Science Beat: Round 2, Science Beat: Round 3, Science Beat: Round 4, Science Song Playlist, The Science Life, Scientist Swagger and Battle of The Grad Programs! And if you feel so inspired, make a video of your own, upload it on YouTube and send me a link to include in a future battle!
Chemistry:
Cellular Respiration:
Anatomy and Physiology:
Vote for your favorite in the comments section below and check out other sciency song battles at Science Beat, Science Beat: Round 2, Science Beat: Round 3, Science Beat: Round 4, Science Song Playlist, The Science Life, Scientist Swagger and Battle of The Grad Programs! And if you feel so inspired, make a video of your own, upload it on YouTube and send me a link to include in a future battle!
Monday, September 14, 2015
5 Animal Species With Surprising Memories
We often think of animals as having hilariously short memories – the “memory of a goldfish”, if you will. But many animals have memories that can put yours to shame.
There are many different kinds of memory and each of them is controlled differently by different parts of the brain. Short-term memory can be thought of as the brain’s scratch pad: It holds a small amount of information for a short period of time while your brain decides whether it is worth retaining in long-term memory or if it can just fade away. When a short-term memory becomes a long-term memory, this process is called consolidation and involves physiological changes in the brain.
Long-term memory can be further divided into two main types: procedural memory and declarative memory. Procedural memory is used to remember how to do things and what objects are needed to do those things. Declarative memory is used for recall and can be further divided into memory used to recall facts (semantic memory) and events (episodic memory).Each of these different types of memories are stored in different parts of the brain. Furthermore, different types of facts (remembering faces versus numbers, for example) and different types of events (depending on if they have an emotional component or not, for example) are also stored in the brain differently. Because species differ in how we rely on our brains, it makes sense that this might be reflected in our abilities to remember in different ways.
So let’s check out some of the most amazing memories in the animal kingdom:
1) They say an elephant never forgets. Elephants are very social animals that live in large stable herds. This has led to some incredible feats of social memory. They can keep track of the whereabouts of 30 group members at once and they can remember an animal they briefly met over 20 years ago. For an animal that lives about 50 or 60 years, this is very impressive. Elephants also have outstanding episodic memory: In 1993, Tarangire National Park in Tanzania suffered the worst drought that it had seen in 35 years. It was so severe that it killed 20% of elephant calves, compared to the average loss of about 2%. Of three herds that lived in the park in 1993, two of them were led by females that had lived during the severe droughts of 1958-61 and those herds left the park and were more successful at finding food and water. The herd that stayed was led by a younger female that had never experienced such a severe drought and that herd suffered 63% of the total mortality.
2) Bottlenose dolphins have even more incredible social memories. They, like elephants, live in complex social groups. Each dolphin has a unique whistle that it uses like a name. When they are played recordings of whistles of companions they lived with years or even decades earlier, they approach the speakers for longer than when they are played the whistles of dolphins they never met. The fact that they, like elephants, remember companions for over 20 years is much more impressive because their lifespan is only 40-50 years!
3) Sea lions have amazing procedural memory. In 1991, marine biologists at the University of California, Santa Cruz, taught a California sea lion named Rio a card trick. They held up one card with a letter or number on it and another set of two cards: one that matched the first card and one that did not. Rio learned to pick the matching card to be rewarded with a fish. Everyone was impressed and she didn't do the trick again... until 10 years later, when researchers pulled out the cards and asked her to do it again. Rio had the same score in 2001 with no practice that she did in 1991 when she originally learned the trick!
4) Clark’s nutcrackers can remember the exact location of 30,000 pine nuts. This kind of superhero ability is born out of necessity: nutcrackers completely rely on their caches of food to get them through the winter. However, despite their amazing long-term spatial memory, their short-term memory is below average: they can’t even remember the color of a light for 30 seconds.
5) Chimpanzees can put your working memory to shame. Working memory is a form of short-term memory that is applied to a task. A group of researchers taught chimpanzees to do a task in which they were shown the numbers from 1-9 in random locations on a computer screen. When the numbers are covered, chimps can remember where each number was. Furthermore, they only need to see these randomly placed number for a few seconds to get this task correct. In comparison, only people that are considered savants have comparable abilities.
There are many different kinds of memory and each of them is controlled differently by different parts of the brain. Short-term memory can be thought of as the brain’s scratch pad: It holds a small amount of information for a short period of time while your brain decides whether it is worth retaining in long-term memory or if it can just fade away. When a short-term memory becomes a long-term memory, this process is called consolidation and involves physiological changes in the brain.
Long-term memory can be further divided into two main types: procedural memory and declarative memory. Procedural memory is used to remember how to do things and what objects are needed to do those things. Declarative memory is used for recall and can be further divided into memory used to recall facts (semantic memory) and events (episodic memory).Each of these different types of memories are stored in different parts of the brain. Furthermore, different types of facts (remembering faces versus numbers, for example) and different types of events (depending on if they have an emotional component or not, for example) are also stored in the brain differently. Because species differ in how we rely on our brains, it makes sense that this might be reflected in our abilities to remember in different ways.
So let’s check out some of the most amazing memories in the animal kingdom:
Do you know what all your kids and nieces and nephews are doing right now? These elephants do. Photo by PJ KAPDostie at Wikimedia. |
Dolphins never forget a name. Photo from the NOAA Photo Library available at Wikimedia. |
Sea lions can remember meaningless tricks for years. Photo by LSA2886 at Wikimedia. |
Clark's nutcrackers can remember where they stashed 30,000 pine nuts.I can't even keep track of my keys. Photo by Gunnsteinn Jonsson at Wikimedia. |
5) Chimpanzees can put your working memory to shame. Working memory is a form of short-term memory that is applied to a task. A group of researchers taught chimpanzees to do a task in which they were shown the numbers from 1-9 in random locations on a computer screen. When the numbers are covered, chimps can remember where each number was. Furthermore, they only need to see these randomly placed number for a few seconds to get this task correct. In comparison, only people that are considered savants have comparable abilities.
Monday, September 7, 2015
Dogs Have Co-opted Our Physiology to Win Our Hearts
Photo by Roberto Ferrari at Wikimedia Commons. |
Today at Accumulating Glitches, I am exploring new research about how our four-legged best friends change our brain physiology so we will love and care for them more. Check out the full story here.
And this is why we love our dogs so much:
Further reading:
MacLean, E.L. and Hare, B. Dogs hijack the human bonding pathway, Science, 438:6232, 280-281 (2015). DOI: 10.1126/science.aab1200
Nagasawa, M., Mitsui, S., En, S., Ohtani, N., Ohta, M., Sakuma, Y., Onaka, T., Mogi, K.., and Kikusui, T. Oxytocin-gaze positive loop and the coevolution of human-dog bonds, Science, 438:6232, 333-336 (2015). DOI:10.1126/science.1261022
Monday, August 31, 2015
Cow Pies Can Make You Smarter and Less Stressed
It seems like everyone is running around buying school supplies and books, registering for classes, and fretting about how hard it is going to be to learn another whole year’s worth of stuff. The secret to success, it turns out, may lie in cow dung.
Recent research has highlighted the important role that microbes living in animal digestive tracts have on host animals’ health and behavior. This influence of our gut microbes on our behavior is called the microbiota-gut-brain axis. Many of these microbes have long-standing populations that reproduce and spend their whole lives in our guts. Because our digestive tracts do not have much oxygen, these species are anaerobic (do not require oxygen to live). However, our gut communities also have more transient aerobic members (species that do require oxygen to live) that come in when they are ingested and die or leave with the droppings. One of these transient aerobic intestinal citizens is Mycobacterium vaccae (or M. vaccae for short), an aerobic bacterium that naturally lives in soil, water, and yes, cow dung.
When mice are injected with heat-killed M. vaccae, they develop an immune response that activates their brain serotonin system and reduces signs of stress. Serotonin is a neurotransmitter that is found in the brain and is involved in regulating alertness, mood, learning and memory. In fact, many antidepressant drugs work by increasing the amount of available serotonin in the brain. Interestingly, serotonin is also found in the digestive system, where it plays a role in digestive health. Since M. vaccae can increase serotonin function, and serotonin reduces anxiety and improves learning, researchers Dorothy Matthews and Susan Jenks at The Sage Colleges in New York set out to test whether eating live M. vaccae could reduce anxiety and improve learning in mice.
The researchers developed a Plexiglas mouse-maze with three difficulty levels, where each increase in difficulty was marked by more turns and a longer path. They encouraged the mice to run the maze by placing a tasty treat (a square of peanut butter on Wonder Bread™) at the end of the maze. Half of the mice were given live M. vaccae on the peanut butter and bread treat three weeks and one week before running the maze, and then again on each treat at the end of each maze run. The other half were given peanut butter and bread without the bacterial additive. The mice then ran the maze roughly every other day: four times at level 1, four times at level 2 and four times at level 3. Each maze run was video recorded and the researchers later watched the videos to count stress-related behaviors.
The mice that ingested M. vaccae on their peanut butter sandwiches completed the maze twice as fast as those that ate plain peanut butter sandwiches. They also had fewer stress-related behaviors, particularly at the first difficulty level of the maze when everything was new and scary. In general, the fewer stress behaviors a mouse did, the faster its maze-running time was. The mice that ate the M. vaccae also tended to make fewer mistakes.
The researchers then wanted to know how long the effects of M. vaccae lasted. They continued to test the mice in the same maze, again with four runs at level 1, four runs at level 2 and four runs at level 3, but for these maze runs no one was given the M. vaccae. The mice that had previously eaten the M. vaccae continued to complete the maze faster and with fewer mistakes and to show fewer stress-related behaviors for about the first week before the M. vaccae effects wore off.
What does this all mean? It means eating dirt isn’t all bad (although I don't recommend eating cow poop). Letting yourself get a bit dirty and ingesting some of nature's microbes could even help you learn better, remember more, and stay calm - especially in new situations. Just something to think about as the school year gets started.
Want to know more? Check these out:
1. Matthews, D., & Jenks, S. (2013). Ingestion of Mycobacterium vaccae decreases anxiety-related behavior and improves learning in mice Behavioural Processes, 96, 27-35 DOI: 10.1016/j.beproc.2013.02.007
2. Lowry, C., Hollis, J., de Vries, A., Pan, B., Brunet, L., Hunt, J., Paton, J., van Kampen, E., Knight, D., Evans, A., Rook, G., & Lightman, S. (2007). Identification of an immune-responsive mesolimbocortical serotonergic system: Potential role in regulation of emotional behavior Neuroscience, 146 (2), 756-772 DOI: 10.1016/j.neuroscience.2007.01.067
A cow pie. Photo taken by Jeff Vanuga at the USDA available at Wikimedia Commons. |
When mice are injected with heat-killed M. vaccae, they develop an immune response that activates their brain serotonin system and reduces signs of stress. Serotonin is a neurotransmitter that is found in the brain and is involved in regulating alertness, mood, learning and memory. In fact, many antidepressant drugs work by increasing the amount of available serotonin in the brain. Interestingly, serotonin is also found in the digestive system, where it plays a role in digestive health. Since M. vaccae can increase serotonin function, and serotonin reduces anxiety and improves learning, researchers Dorothy Matthews and Susan Jenks at The Sage Colleges in New York set out to test whether eating live M. vaccae could reduce anxiety and improve learning in mice.
A drawing of the mouse maze used by Dorothy and Susan. This image is from their 2013 Behavioural Processes paper. |
The mice that ingested M. vaccae on their peanut butter sandwiches completed the maze twice as fast as those that ate plain peanut butter sandwiches. They also had fewer stress-related behaviors, particularly at the first difficulty level of the maze when everything was new and scary. In general, the fewer stress behaviors a mouse did, the faster its maze-running time was. The mice that ate the M. vaccae also tended to make fewer mistakes.
The researchers then wanted to know how long the effects of M. vaccae lasted. They continued to test the mice in the same maze, again with four runs at level 1, four runs at level 2 and four runs at level 3, but for these maze runs no one was given the M. vaccae. The mice that had previously eaten the M. vaccae continued to complete the maze faster and with fewer mistakes and to show fewer stress-related behaviors for about the first week before the M. vaccae effects wore off.
What does this all mean? It means eating dirt isn’t all bad (although I don't recommend eating cow poop). Letting yourself get a bit dirty and ingesting some of nature's microbes could even help you learn better, remember more, and stay calm - especially in new situations. Just something to think about as the school year gets started.
Want to know more? Check these out:
1. Matthews, D., & Jenks, S. (2013). Ingestion of Mycobacterium vaccae decreases anxiety-related behavior and improves learning in mice Behavioural Processes, 96, 27-35 DOI: 10.1016/j.beproc.2013.02.007
2. Lowry, C., Hollis, J., de Vries, A., Pan, B., Brunet, L., Hunt, J., Paton, J., van Kampen, E., Knight, D., Evans, A., Rook, G., & Lightman, S. (2007). Identification of an immune-responsive mesolimbocortical serotonergic system: Potential role in regulation of emotional behavior Neuroscience, 146 (2), 756-772 DOI: 10.1016/j.neuroscience.2007.01.067
Monday, August 24, 2015
The Weirdest Animals on Earth: 12 Amazing Facts About Octopuses
1. The plural of octopus is octopuses. How an English word is pluralized depends, in part, on its origins. Latin words that end in –us are generally pluralized by replacing the –us with an –i (the plural of alumnus, for example, is alumni). But octopus is not Latin – It comes from the ancient Greek word októpous, whose plural is októpodes. Although octopodes is technically correct, since it has been adopted into the English language, the word is now pluralized in the English way, making it octopuses. So octopi is commonly used but not technically correct, octopodes is technically correct but not commonly used and octopussies is just plain wrong.
2. Octopuses are mollusks. This means that they are not only closely related to squid and cuttlefish, but also to clams, oysters, snails and slugs.
3. Octopuses are crazy-smart. They can solve problems, learn from watching others, use tools, and remember experiences. They even have personalities and play with toys. Check this out:
4. Octopuses have nine brains! Rather than a large centralized brain like ours, octopus brains are more like the internet. Their main CPU is a fairly small brain in their head, but each of their eight arms has an additional brain of its own. In fact, two-thirds of an octopus’ neurons are in the arms, which can independently attach to things, push things, and even smell things. They can even react after they have been severed! Not only that, but their severed arms recognize their previous owner:
5. If an octopus loses an arm, it can grow back. Those crazy arms are like the brooms in Disney's Sorcerer's Apprentice in Fantasia!
6. Octopuses are amazing camouflage artists. Their soft bodies can squeeze into ridiculously small cracks and crevices and take on any number of shapes. A 50-pound octopus, for example, can squeeze through a 2-inch hole! They can also change the color and texture of their skin to match their background.
The mimic octopus, the ultimate master of disguise, doesn’t just imitate their background, but also flounders, starfish, poisonous lionfish, and sea snakes.
7. Octopuses don’t have visual blind-spots. Most animal eyes detect light patterns when light travels to the retina (the layer in the back of the eye) and falls on photoreceptor cells, causing the cells to send electrical signals through the optic nerve to the brain. Vertebrate photoreceptor cells face backwards, so their nerve fibers come in front of the retina and then exit the eye together through the optic nerve, creating a small region in the back of the eye with no photoreceptor cells. If light falls on this spot, we literally will not see it, although our brain will compensate for this missing light by imagining what should be there based on the rest of what we see. We call this our blind spot. You can test your blind spot by closing your left eye and focusing your right eye on the “R” below. Move your face towards or away from the screen until the “L” disappears. You can test your left eye by staring at the “L” in the same way.
In octopus eyes, the photoreceptor cells face forwards and the nerve fibers go behind the retina. This means that they have a continuous layer of photoreceptor cells and no blind spot.
8. Octopuses are more blue blooded than police officers. Their blood is truly blue, due to the fact that they don’t have hemoglobin, our respiratory pigment that contains iron and turns red when it binds to oxygen. Rather, they have hemocyanin, which contains copper and turns blue when oxygen binds to it.
9. Octopuses have three hearts! They have two small hearts that each pump blood through the gills and a main systemic heart that collects the blood and pumps it through the circulatory system.
10. Octopus ink is a defensive chemical concoction. It not only obscures the view of an attacker, but it also contains a chemical that irritates the predator’s eyes and temporarily paralyzes its sense of smell.
11. Octopuses bite with a bird-like beak and venomous saliva, which is mostly used to subdue prey. Of the approximately 300 octopus species, only the small blue-ringed octopus is known to be deadly to humans.
12. Octopuses die after they mate for the first time. And they mate in an odd way too: males use the tip of their third arm on the right to either insert their spermatophores (sperm packets) directly into the female’s tubular breathing funnel or he just hands it to her (The tip of the third right arm can be used to tell if an octopus is male or female). If he hands it to her, she accepts it with one of her right arms (we don’t know why they’re right-handed this way). Then the males go off to die. The females eventually lay up to 400,000 fertilized eggs, although they can wait months before they do this. She tends them and guards them at the exclusion of all else until they hatch, at which point her body rapidly deteriorates as her cells die off.
Photo of a day octopus by Ahmed Abdul Rahman available at Wikimedia Commons. |
2. Octopuses are mollusks. This means that they are not only closely related to squid and cuttlefish, but also to clams, oysters, snails and slugs.
3. Octopuses are crazy-smart. They can solve problems, learn from watching others, use tools, and remember experiences. They even have personalities and play with toys. Check this out:
4. Octopuses have nine brains! Rather than a large centralized brain like ours, octopus brains are more like the internet. Their main CPU is a fairly small brain in their head, but each of their eight arms has an additional brain of its own. In fact, two-thirds of an octopus’ neurons are in the arms, which can independently attach to things, push things, and even smell things. They can even react after they have been severed! Not only that, but their severed arms recognize their previous owner:
5. If an octopus loses an arm, it can grow back. Those crazy arms are like the brooms in Disney's Sorcerer's Apprentice in Fantasia!
6. Octopuses are amazing camouflage artists. Their soft bodies can squeeze into ridiculously small cracks and crevices and take on any number of shapes. A 50-pound octopus, for example, can squeeze through a 2-inch hole! They can also change the color and texture of their skin to match their background.
The mimic octopus, the ultimate master of disguise, doesn’t just imitate their background, but also flounders, starfish, poisonous lionfish, and sea snakes.
A vertebrate eye (left) versus an octopus eye (right). 1: Retina, 2: Nerve fibers, 3: Optic nerve, 4: Blind spot. Image by Jerry Crimson Mann at Wikimedia. |
In octopus eyes, the photoreceptor cells face forwards and the nerve fibers go behind the retina. This means that they have a continuous layer of photoreceptor cells and no blind spot.
8. Octopuses are more blue blooded than police officers. Their blood is truly blue, due to the fact that they don’t have hemoglobin, our respiratory pigment that contains iron and turns red when it binds to oxygen. Rather, they have hemocyanin, which contains copper and turns blue when oxygen binds to it.
9. Octopuses have three hearts! They have two small hearts that each pump blood through the gills and a main systemic heart that collects the blood and pumps it through the circulatory system.
10. Octopus ink is a defensive chemical concoction. It not only obscures the view of an attacker, but it also contains a chemical that irritates the predator’s eyes and temporarily paralyzes its sense of smell.
11. Octopuses bite with a bird-like beak and venomous saliva, which is mostly used to subdue prey. Of the approximately 300 octopus species, only the small blue-ringed octopus is known to be deadly to humans.
12. Octopuses die after they mate for the first time. And they mate in an odd way too: males use the tip of their third arm on the right to either insert their spermatophores (sperm packets) directly into the female’s tubular breathing funnel or he just hands it to her (The tip of the third right arm can be used to tell if an octopus is male or female). If he hands it to her, she accepts it with one of her right arms (we don’t know why they’re right-handed this way). Then the males go off to die. The females eventually lay up to 400,000 fertilized eggs, although they can wait months before they do this. She tends them and guards them at the exclusion of all else until they hatch, at which point her body rapidly deteriorates as her cells die off.
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