Cats and dogs are colour blind
The myth that cats and dogs only see in black and white has been around for quite a while. However, this cant be any further from the truth. Cats and dogs can see colour. So where did this myth originate from? In 1915 at the University of Colorado, two scientists were trying to determine whether cats could see colors and so devised an experiment like so: two jars, one wrapped with gray paper, one wrapped with colored paper, were placed before the cat. If the cat touched the colored jar with its nose or paw or the like, it would get a tiny fish. If it touched the gray jar, it got nothing. After 18 months and 100,000 tries, the cats tested only correctly picked the colored jar around half the time. Given that the odds were 50/50 in the first place, it would seem from this that they couldn’t see color. (Perhaps, though, they were just sick of fish after around 50,000 correct guesses between 9 cats, so about 10 little fish per day, per cat, every day, for 18 months. So their picking the gray jar was really just a cry for help. Alternatively, the cats were just screwing with the humans, because, you know… cats.)
Given the large sample-size, this particular bit of research was accepted and for a time it was considered “fact” that cats were completely colorblind. However, cats did have both cones and rods in their eyes, which seemed to fly in the face of the above research. If they have both, why couldn’t cats see color? Enter a more advanced scientific experiment: using electrodes, neurologists wired up a cat’s brain and showed the cat various shades of color. What they found was that the cat’s brain did respond and distinguished between many shades of color. Hence, they could perceive color. This is the same case for dogs.
In any event, cats are partially colorblind in that they seem to lack the ability to see red, or at least not strongly, but have no problem with blues and greens.
Dogs do have significantly fewer cones than humans, though, so scientists estimate that they only see colors about 1/7th as vibrant as humans do. Despite this, dogs were quickly able to learn to distinguish not only gray from various colors, but also to easily distinguish between many shades of colors. Like cats, though, dogs are partially colorblind. Specifically, due to lack of L-cones they have trouble with differentiating between red, orange, and chartreuse shades, though they can do things like distinguish red and blue and distinguish between the various shades of blue and the like.
AS BLIND AS A.................
As blind as a.....yeah you guessed it, bat. But the irony is bats are not blind at all. The fact that they use echolocation to fly does not mean they cant see. Just because these creatures use echolocation their sight also helps them to navigate. The same for dolphins which use echolocation therefore it cant be concluded that they are blind. The English language got it wrong on this one.
SHARKS CAN DETECT BLOOD FROM MILES
Shark movies have greatly exaggerated this myth far and beyond. The thought that sharks can detect a drop of blood from miles away is far fetched to say the least. This however does not rule out the fact that sharks have an incredible sense of smell.
Sharks' nostrils are located on the underside of the snout, and unlike human nostrils, are used solely for smelling and not for breathing. They are lined with specialized sensitive cells to detect smells. Water flows into the nostrils and dissolved chemicals come into contact with tissue, exciting receptors in the cells. These signals are then transmitted to the brain and are interpreted as smells.
Because of the extreme sensitivity of these cells, as well as the fact that the olfactory bulb of the brain is enlarged, sharks can detect miniscule amounts of certain chemicals. This varies, of course, among different species of sharks and the chemical in question. The lemon shark can detect tuna oil at one part per 25 million--that's equivalent to about 10 drops in an average-sized home swimming pool. Other types of sharks can detect their prey at one part per 10 billion; that's one drop in an Olympic-sized swimming pool! So the next time your in the ocean bleeding and a shark is miles away then there is no chance it will detect it.
GIRAFFES SLEEP FOR ONLY 30 MIN
I have to say I believed this myth until the day I read the scientific research behind it. Giraffes have fairly normal sleeping patterns, as far as diurnal animals go.
To debunk this one, researchers closely monitored a herd of five adult and three young giraffes for 152 days, counting all of their naps and deep sleeps. The animals typically slept overnight and napped in the afternoon. In total, each giraffe slept about 4.6 hours every day.
GOLD FISH HAVE A SHORT MEMORY
There is a popular belief that goldfish only have a three-second memory span and every lap of their fishbowl is like seeing the world for the first time.
Children's films like Disney's Finding Nemo - in which one of the main characters is a dory who suffers from short-term memory loss - have done little to help dispel the myth that fish are dumb.
But a 15-year-old schoolboy from Adelaide has debunked that theory. He decided to get a piece of red lego and feed the fish next to it. At first they were scared but after three weeks they got used to it.
After leaving the fish alone for a week, Rory placed the red Lego block in the tank again.
"They remembered perfectly well," he said.
The goldfish showed that not only could they retain information, they also had the ability to recall it at a later date. Not so forgetful after all.
If you didn't know now you know. Part two of myth busters will be out soon. Make sure to subscribe.
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