Monkey see, monkey do Mathematical calculations
Humans are constantly making decisions with uncertain outcomes—betting on a poker hand, predicting the weather, and selecting a lane of traffic, for example. Because the consequences of such decisions are not guaranteed, we must base our decisions on clues from the environment, determining the probabilities of potential outcomes before deciding on a rational course of action.
How does the brain perform these calculations? During the formation of a decision, what happens between sensation (our interpretation of the outside world) and behavior (the manifestation of our decision)?
To answer these questions, Tianming Yang and Michael Shadlen from the University of Washington trained Rhesus Monkeys to perform "simple" statistical calculations, and measured the activity of particular neurons during the decision-making process. The results were published on June 3 in an advance online publication in Nature.
In the task, the monkeys were presented with a random series of four abstract shapes on a video screen. They then directed their gaze toward either a red or a green target light, only one of which would be associated with a juice reward. The light that would give the reward was not fixed, but could be calculated probabilistically.
Each shape (there were a total of 10) represented the probability that the rewarding target was either red or green. For example, a square strongly favors the red target as rewarding (weighted 0.9), while a triangle indicates that green will be rewarding (0.9 in the opposite direction). A cone weakly indicates the red will be rewarding (0.5 towards red), and a pac-man weakly indicates green (0.3). Thus, the probability that the monkey will be rewarded by looking at a particular target is the sum of the probabilities for each of the shapes.
With 10 shapes, there are 715 unique combinations (and 10^4 permutations), thus precluding memorization of specific four-shape patterns, and encouraging the monkeys to learn the shapes and calculate the reward probability of each target. This is a far from trivial demand of a monkey, but eventually (after two months and over 130,000 trials), they chose the correct target 75% of the time, indicating that they had learned to base their decisions on the combined probabilities for reward. This capacity of monkeys to make such subtle probabilistic deductions is quite impressive, but is only the first half of the story.
After thus establishing a complex reasoning task, the researchers could begin exploring the neural basis for these types of decisions. They measured the activity of neurons in a particular area of the brain, called the lateral intraparietal area (LIP). This area lies intermediate between the visual input (the abstract shapes) and the behavioral output (the appropriate eye movement), and is thought to carry information involved in transforming visual signals into commands to move the eyes; i.e. in making decisions that result in eye movements.
What they found was awesome. When the monkeys saw a shape, the activity of their LIP neurons was proportional to the probability associated with that shape. With each sequential shape, the neurons altered their firing rates to match the updated probability. Although it is unknown how their brains converted information from each shape to their respective probabilities, the activity of these neurons indicates that they either play a role in the transformation, or represent the outcome during the decision-making process.
Apart from showing that monkeys are closer to furry calculators than previously thought, the study has grander implications. As the authors conclude, “the present study exposes the brain’s capacity to extract probabilistic information from a set of symbols and to combine this information over time.” A similar neural process may underlie our abilities to reason about alternatives, and make decisions based on subtle probabilistic differences.
Humans are constantly making decisions with uncertain outcomes—betting on a poker hand, predicting the weather, and selecting a lane of traffic, for example. Because the consequences of such decisions are not guaranteed, we must base our decisions on clues from the environment, determining the probabilities of potential outcomes before deciding on a rational course of action.
How does the brain perform these calculations? During the formation of a decision, what happens between sensation (our interpretation of the outside world) and behavior (the manifestation of our decision)?
To answer these questions, Tianming Yang and Michael Shadlen from the University of Washington trained Rhesus Monkeys to perform "simple" statistical calculations, and measured the activity of particular neurons during the decision-making process. The results were published on June 3 in an advance online publication in Nature.
In the task, the monkeys were presented with a random series of four abstract shapes on a video screen. They then directed their gaze toward either a red or a green target light, only one of which would be associated with a juice reward. The light that would give the reward was not fixed, but could be calculated probabilistically.
Each shape (there were a total of 10) represented the probability that the rewarding target was either red or green. For example, a square strongly favors the red target as rewarding (weighted 0.9), while a triangle indicates that green will be rewarding (0.9 in the opposite direction). A cone weakly indicates the red will be rewarding (0.5 towards red), and a pac-man weakly indicates green (0.3). Thus, the probability that the monkey will be rewarded by looking at a particular target is the sum of the probabilities for each of the shapes.
With 10 shapes, there are 715 unique combinations (and 10^4 permutations), thus precluding memorization of specific four-shape patterns, and encouraging the monkeys to learn the shapes and calculate the reward probability of each target. This is a far from trivial demand of a monkey, but eventually (after two months and over 130,000 trials), they chose the correct target 75% of the time, indicating that they had learned to base their decisions on the combined probabilities for reward. This capacity of monkeys to make such subtle probabilistic deductions is quite impressive, but is only the first half of the story.
After thus establishing a complex reasoning task, the researchers could begin exploring the neural basis for these types of decisions. They measured the activity of neurons in a particular area of the brain, called the lateral intraparietal area (LIP). This area lies intermediate between the visual input (the abstract shapes) and the behavioral output (the appropriate eye movement), and is thought to carry information involved in transforming visual signals into commands to move the eyes; i.e. in making decisions that result in eye movements.
What they found was awesome. When the monkeys saw a shape, the activity of their LIP neurons was proportional to the probability associated with that shape. With each sequential shape, the neurons altered their firing rates to match the updated probability. Although it is unknown how their brains converted information from each shape to their respective probabilities, the activity of these neurons indicates that they either play a role in the transformation, or represent the outcome during the decision-making process.
Apart from showing that monkeys are closer to furry calculators than previously thought, the study has grander implications. As the authors conclude, “the present study exposes the brain’s capacity to extract probabilistic information from a set of symbols and to combine this information over time.” A similar neural process may underlie our abilities to reason about alternatives, and make decisions based on subtle probabilistic differences.
Bulldog
Homemade dog food is becoming a popular option for pet owners everywhere, after the recent commercial dog food contamination scare. What exactly have we been feeding our dogs? What should we be feeding them? We pet owners take for granted that commercial store bought dog food is safe for our beloved pets. Here are the top 7 benefits that homemade dog food has to offer your canine friend.
1. Homemade dog food allows you to know exactly what your dog is eating. You don’t have to worry about contaminated food, unfit ingredients, or harmful preservatives.
2. Homemade dog food helps your dog to maintain a healthier weight. By preparing your dogs food, you are able to calorie control meals.
3. Homemade dog food helps your dog to have more energy. Homemade dog food gives your dog better quality nutrition, which helps him or her to feel better and be more playful.
4. Homemade dog food can help your dog to have a healthier digestive tract. Dogs that eat homemade dog food have less gas, smaller stools, and better smelling breath.
5. Homemade dog food can help your dog to have healthier skin. Dogs that eat homemade dog food have less shedding, a shinier coat, and better smelling fur.
6. Homemade dog food can save your money. It is true, homemade dog food actually ends up costing you less than the same amount of store bought dog food.
7. Dogs love the taste of homemade dog food. They prefer fresh, preservative free home cooking just as much as we do.
Homemade dog food is becoming a popular option for pet owners everywhere, after the recent commercial dog food contamination scare. What exactly have we been feeding our dogs? What should we be feeding them? We pet owners take for granted that commercial store bought dog food is safe for our beloved pets. Here are the top 7 benefits that homemade dog food has to offer your canine friend.
1. Homemade dog food allows you to know exactly what your dog is eating. You don’t have to worry about contaminated food, unfit ingredients, or harmful preservatives.
2. Homemade dog food helps your dog to maintain a healthier weight. By preparing your dogs food, you are able to calorie control meals.
3. Homemade dog food helps your dog to have more energy. Homemade dog food gives your dog better quality nutrition, which helps him or her to feel better and be more playful.
4. Homemade dog food can help your dog to have a healthier digestive tract. Dogs that eat homemade dog food have less gas, smaller stools, and better smelling breath.
5. Homemade dog food can help your dog to have healthier skin. Dogs that eat homemade dog food have less shedding, a shinier coat, and better smelling fur.
6. Homemade dog food can save your money. It is true, homemade dog food actually ends up costing you less than the same amount of store bought dog food.
7. Dogs love the taste of homemade dog food. They prefer fresh, preservative free home cooking just as much as we do.
Mamba
Mamba, of the genus Dendroaspis, are fast-moving tree-dwelling snakes of Africa. ("Dendroaspis" is literally "tree snake".) They belong to the family of Elapidae which includes cobras, coral snakes, kraits, and debatedly sea snakes, all of which can be extremely deadly. The black mamba is the largest venomous snake in Africa, with an extremely potent neurotoxic venom that attacks the nervous system; the bite is often fatal to humans without access to proper first aid and subsequent antivenom treatment, because it shuts down the lungs and heart. Prior to the availability of antivenom, envenomations by members of this genus carried a nearly 100% fatality rate. However, with antivenom being much more available today, fatalities have become much more rare. Many people have survived treatment without the use of antivenoms. Mambas will detect and get away from humans as fast as possible.
Mamba, of the genus Dendroaspis, are fast-moving tree-dwelling snakes of Africa. ("Dendroaspis" is literally "tree snake".) They belong to the family of Elapidae which includes cobras, coral snakes, kraits, and debatedly sea snakes, all of which can be extremely deadly. The black mamba is the largest venomous snake in Africa, with an extremely potent neurotoxic venom that attacks the nervous system; the bite is often fatal to humans without access to proper first aid and subsequent antivenom treatment, because it shuts down the lungs and heart. Prior to the availability of antivenom, envenomations by members of this genus carried a nearly 100% fatality rate. However, with antivenom being much more available today, fatalities have become much more rare. Many people have survived treatment without the use of antivenoms. Mambas will detect and get away from humans as fast as possible.
Python
Python,the common name for a group of non-venomous constricting snakes, specifically the family Pythonidae. Other sources consider this group a subfamily of the Boas (Pythoninae). Pythons are more related to boas than to any other snake-family. There is also a genus within Pythonidae which carries the name Python (Daudin, 1803). Pythons are distinguishable from boas in that they have teeth on the premaxilla, a small bone at the very front and center of the upper jaw. Most boas produce live young, while pythons produce eggs. Some species of sand boas (Ericinae) are also called python.
Sheep in a snake
Sounds like a great name for a film, eh? In fact, we just cannot resist posting this picture of a python that has swallowed a pregnant ewe.
The photo was taken in the Malaysian village of Kampung Jabor, east of Kuala Lumpur. The Reuters caption adds that the six-metre reptile weighed 90kg and was "too laden to move, making it easy for firemen to capture it".
Python,the common name for a group of non-venomous constricting snakes, specifically the family Pythonidae. Other sources consider this group a subfamily of the Boas (Pythoninae). Pythons are more related to boas than to any other snake-family. There is also a genus within Pythonidae which carries the name Python (Daudin, 1803). Pythons are distinguishable from boas in that they have teeth on the premaxilla, a small bone at the very front and center of the upper jaw. Most boas produce live young, while pythons produce eggs. Some species of sand boas (Ericinae) are also called python.
Sheep in a snake
Sounds like a great name for a film, eh? In fact, we just cannot resist posting this picture of a python that has swallowed a pregnant ewe.
The photo was taken in the Malaysian village of Kampung Jabor, east of Kuala Lumpur. The Reuters caption adds that the six-metre reptile weighed 90kg and was "too laden to move, making it easy for firemen to capture it".
Anaconda
Range: South America, North and East Central.
Habitat: Always found near water, swamp environments. The flooded Pantanal region of Venezuela is classic Anaconda habitat.
Natural Diet: Mammals, birds, fish and small crocodilians.
Diet at RainForest: Pre-killed rodents Size: Females 12-18 feet, Males 6-11 feet
RainForest Facts: The heaviest of all living snakes, the female Anaconda can reach lengths of 20 feet and weights of over 300 pounds. Male Anacondas are considerably smaller than females, a large male may only be 8-10 feet in length and is a considerably thinner bodied animal. A highly aquatic snake, the Anaconda is much more likely to be encountered in the wild in or near a body of freshwater. The name Anaconda literally translates to "Water Boa"
The Anaconda is considered by many to be an aggressive animal in captivity. Anacondas have a very large number of sharp, rear-facing teeth.
A long lived animal in captivity, the Anaconda may live as long as thirty years. In the wild predators of even large females undoubtedly shorten the average life span. Large Black Caiman have been observed killing and eating females of up to 15 feet in length.
Anacondas mate in an unusual fashion. Several males are attracted to an ovulating female resulting in a "mating ball" that can often obscure the female from view. The mating always takes place in water. After a gestation of six months the females give birth to live babies in the late spring to early summer, birth generally coincides with the wet season in the animals native range. A large female is capable of producing up to 80 babies at a time, on average the female Anaconda will have 20-30 young. Predators account for a high mortality among juvenile Anacondas, Tegu lizards, birds of prey and crocodilians all consume young snakes.
Female Anacondas can reproduce as early as 4 years of age.
One recognized subspecies of Anaconda lives in the southern end of the Green Anacondas range, the Yellow Anaconda. The Yellow Anaconda is a smaller, and more brightly colored snake. A large Yellow Anaconda may only attain a length of 8 feet compared to well over 15 feet for a large Green Anaconda. Like the Green Anaconda, the Yellow Anaconda gives birth to live babies. The litters are slightly smaller in average number than the Green Anaconda, 10-20 is an average number of babies born to a healthy female Yellow Anaconda.
All Pythons are constrictors. Snakes that hunt using constriction as a means of subduing prey will very quickly grab their prey with their teeth using a very fast strike. The constrictor will quickly wrap coils of their bodies around the prey and squeeze or constrict the prey item. This process does not actually crush the prey and break its bones as is widely reported in the media. Instead, they squeeze tightly so that the prey animal can’t breath and it suffocates, this process usually requires about 3-4 minutes for the prey animal to be killed.
Once the snake is certain the prey item is dead they then begin to search for the animals head, virtually all prey animals are consumed head first. This process allows the snake to literally "fold" the arms and legs of the prey animal back as the creature is swallowed. Contrary to popular belief a snake does not "unhinge" it's jaws, the jaws in fact are not actually attached in a mechanical way. Long tendons and muscles connect the upper and lower jaws. The lower jaw is actually made up of two separate bones to further enhance the animals ability to manipulate large prey items.
Once the snake has the animal past it's jaws a series rhythmic muscular contractions then pull the prey down the snake’s throat and into its stomach. A very large prey item can be observed in the snakes stomach as a large bulge. Contrary to popular belief the large prey item is not digested by slowing moving down the length of the snake. Once the prey animal reaches the stomach, usually about 20 minutes for a very large item, the food item is stationary in the snakes stomach as it is gradually digested. The size of the meal can have an impact on the duration of the digestion, but external factors such as ambient air temperature play a larger roll. The snake must be careful not to eat when temperatures are too cool, the meal will quite literally decompose faster than the snake can digest it, causing a gaseous bloating in the snake that can result in death. Ideal air temperatures allow the snake to digest the meal prior to the food item decomposing! Snakes often will regurgitate a meal when the conditions do not allow it to properly digest the meal, this can include both temperatures that are too high and too low!
Member of the boa family, South America’s green anaconda is, pound for pound, the largest snake in the world. Its cousin, the reticulated python, can reach slightly greater lengths, but the enormous girth of the anaconda makes it almost twice as heavy.
Green anacondas can grow to more than 29 feet (8.8 meters), weigh more than 550 pounds (227 kilograms), and measure more than 12 inches (30 centimeters) in diameter. Females are significantly larger than males. Other anaconda species, all from South America and all smaller than the green anaconda, are the yellow, dark-spotted, and Bolivian varieties.
Anacondas live in swamps, marshes, and slow-moving streams, mainly in the tropical rain forests of the Amazon and Orinoco basins. They are cumbersome on land, but stealthy and sleek in the water. Their eyes and nasal openings are on top of their heads, allowing them to layin
Range: South America, North and East Central.
Habitat: Always found near water, swamp environments. The flooded Pantanal region of Venezuela is classic Anaconda habitat.
Natural Diet: Mammals, birds, fish and small crocodilians.
Diet at RainForest: Pre-killed rodents Size: Females 12-18 feet, Males 6-11 feet
RainForest Facts: The heaviest of all living snakes, the female Anaconda can reach lengths of 20 feet and weights of over 300 pounds. Male Anacondas are considerably smaller than females, a large male may only be 8-10 feet in length and is a considerably thinner bodied animal. A highly aquatic snake, the Anaconda is much more likely to be encountered in the wild in or near a body of freshwater. The name Anaconda literally translates to "Water Boa"
The Anaconda is considered by many to be an aggressive animal in captivity. Anacondas have a very large number of sharp, rear-facing teeth.
A long lived animal in captivity, the Anaconda may live as long as thirty years. In the wild predators of even large females undoubtedly shorten the average life span. Large Black Caiman have been observed killing and eating females of up to 15 feet in length.
Anacondas mate in an unusual fashion. Several males are attracted to an ovulating female resulting in a "mating ball" that can often obscure the female from view. The mating always takes place in water. After a gestation of six months the females give birth to live babies in the late spring to early summer, birth generally coincides with the wet season in the animals native range. A large female is capable of producing up to 80 babies at a time, on average the female Anaconda will have 20-30 young. Predators account for a high mortality among juvenile Anacondas, Tegu lizards, birds of prey and crocodilians all consume young snakes.
Female Anacondas can reproduce as early as 4 years of age.
One recognized subspecies of Anaconda lives in the southern end of the Green Anacondas range, the Yellow Anaconda. The Yellow Anaconda is a smaller, and more brightly colored snake. A large Yellow Anaconda may only attain a length of 8 feet compared to well over 15 feet for a large Green Anaconda. Like the Green Anaconda, the Yellow Anaconda gives birth to live babies. The litters are slightly smaller in average number than the Green Anaconda, 10-20 is an average number of babies born to a healthy female Yellow Anaconda.
All Pythons are constrictors. Snakes that hunt using constriction as a means of subduing prey will very quickly grab their prey with their teeth using a very fast strike. The constrictor will quickly wrap coils of their bodies around the prey and squeeze or constrict the prey item. This process does not actually crush the prey and break its bones as is widely reported in the media. Instead, they squeeze tightly so that the prey animal can’t breath and it suffocates, this process usually requires about 3-4 minutes for the prey animal to be killed.
Once the snake is certain the prey item is dead they then begin to search for the animals head, virtually all prey animals are consumed head first. This process allows the snake to literally "fold" the arms and legs of the prey animal back as the creature is swallowed. Contrary to popular belief a snake does not "unhinge" it's jaws, the jaws in fact are not actually attached in a mechanical way. Long tendons and muscles connect the upper and lower jaws. The lower jaw is actually made up of two separate bones to further enhance the animals ability to manipulate large prey items.
Once the snake has the animal past it's jaws a series rhythmic muscular contractions then pull the prey down the snake’s throat and into its stomach. A very large prey item can be observed in the snakes stomach as a large bulge. Contrary to popular belief the large prey item is not digested by slowing moving down the length of the snake. Once the prey animal reaches the stomach, usually about 20 minutes for a very large item, the food item is stationary in the snakes stomach as it is gradually digested. The size of the meal can have an impact on the duration of the digestion, but external factors such as ambient air temperature play a larger roll. The snake must be careful not to eat when temperatures are too cool, the meal will quite literally decompose faster than the snake can digest it, causing a gaseous bloating in the snake that can result in death. Ideal air temperatures allow the snake to digest the meal prior to the food item decomposing! Snakes often will regurgitate a meal when the conditions do not allow it to properly digest the meal, this can include both temperatures that are too high and too low!
Member of the boa family, South America’s green anaconda is, pound for pound, the largest snake in the world. Its cousin, the reticulated python, can reach slightly greater lengths, but the enormous girth of the anaconda makes it almost twice as heavy.
Green anacondas can grow to more than 29 feet (8.8 meters), weigh more than 550 pounds (227 kilograms), and measure more than 12 inches (30 centimeters) in diameter. Females are significantly larger than males. Other anaconda species, all from South America and all smaller than the green anaconda, are the yellow, dark-spotted, and Bolivian varieties.
Anacondas live in swamps, marshes, and slow-moving streams, mainly in the tropical rain forests of the Amazon and Orinoco basins. They are cumbersome on land, but stealthy and sleek in the water. Their eyes and nasal openings are on top of their heads, allowing them to layin
Under Water
Giant Stuffed Animals
Giant stuffed animals rule the roost in the toy world. They are very big toy animals and are perfect gifts for any occasion, including anniversaries, holidays, weddings, birthdays, and graduations. Giant stuffed animals are especially pleasing to the eye, very soft to touch, and capable of bringing a smile to children and adults alike. Most giant stuffed animals are life-sized, while some are several times larger than life.
A giant stuffed animal appeals to people for a variety of reasons. They are ideal for all occasions and for all ages. They can make any child, animal lover, or adult happy. Life-sized stuffed animals are great friends for children. Giant stuffed animals are eye catching and can be used as a decorative item in homes and business houses alike. A wide range of giant stuffed animals including dinosaurs, giraffes, dogs, elephants, kangaroos, sharks, lions, penguins, deer, horses, reindeer, dragons, and other jungle animals are available on the market. Most of them are cuddly, soft, and have beautiful features and realistic expressions. These impressive animal friends are perfect for play and display.
In the past, giant stuffed animals were objects made of the skins and fur of real animals. Over the years, straw, beans, rice, cotton, and other organic materials have been used in the making of giant stuffed animals. Today, giant stuffed animals are manufactured using synthetic materials such as rubber and polythene.
Owing to of their large size, most giant stuffed animals are expensive. Prices vary with shape, size, color, durability, design, and materials used. One can get giant stuffed animals customized with special clothes, names, logos, and even the photo image of the face of a child or pet. Gift shops and online shops are the best places to look for giant stuffed animals.
Stuffed Animals provides detailed information on Stuffed Animals, Plush Stuffed Animals, Giant Stuffed Animals, Wholesale Stuffed Animals and more. Stuffed Animals is affiliated with Roman Seraphim Angels.
Giant Stuffed Animals
Giant stuffed animals rule the roost in the toy world. They are very big toy animals and are perfect gifts for any occasion, including anniversaries, holidays, weddings, birthdays, and graduations. Giant stuffed animals are especially pleasing to the eye, very soft to touch, and capable of bringing a smile to children and adults alike. Most giant stuffed animals are life-sized, while some are several times larger than life.A giant stuffed animal appeals to people for a variety of reasons. They are ideal for all occasions and for all ages. They can make any child, animal lover, or adult happy. Life-sized stuffed animals are great friends for children. Giant stuffed animals are eye catching and can be used as a decorative item in homes and business houses alike. A wide range of giant stuffed animals including dinosaurs, giraffes, dogs, elephants, kangaroos, sharks, lions, penguins, deer, horses, reindeer, dragons, and other jungle animals are available on the market. Most of them are cuddly, soft, and have beautiful features and realistic expressions. These impressive animal friends are perfect for play and display.
In the past, giant stuffed animals were objects made of the skins and fur of real animals. Over the years, straw, beans, rice, cotton, and other organic materials have been used in the making of giant stuffed animals. Today, giant stuffed animals are manufactured using synthetic materials such as rubber and polythene.
Owing to of their large size, most giant stuffed animals are expensive. Prices vary with shape, size, color, durability, design, and materials used. One can get giant stuffed animals customized with special clothes, names, logos, and even the photo image of the face of a child or pet. Gift shops and online shops are the best places to look for giant stuffed animals.
Stuffed Animals provides detailed information on Stuffed Animals, Plush Stuffed Animals, Giant Stuffed Animals, Wholesale Stuffed Animals and more. Stuffed Animals is affiliated with Roman Seraphim Angels.
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