human eye can detect sound

The human eye can detect millions of colors and is sensitive to light and sounds. Yes, sound. University research studies show that mild and incidental noises cause the pupils of the eyes to dilate.

According to David Louis’s book of Fascinating Facts, it is believed that this is why surgeons, watchmakers, and others who perform delicate manual operations are so bothered by uninvited noise: the sounds cause their pupils to change focus and blur their vision.

The “millions of colors” that the eye can detect are the three primary colors of red, green and blue and the millions of combinations that result from these three colors. (In 1878, Ewald Hering proposed the theory that the four unique hues of red, green, blue, and yellow form the basis of all colors.)

source : http://didyouknow.org/human-eye-detects-sound/

animal facts

Mammals are the only animals with flaps around the ears.

African elephants only have four teeth to chew their food with.

There are about one billion cattle in the world of which 200 million are in India.

A house fly lives only 14 days.

A dog was the first in space and a sheep, a duck and a rooster the first to fly in a hot air balloon.

The Big Five is a group of animals of Africa: cape buffalo, elephant, leopard, lion and rhino.

The oldest breed of dog is the Saluki.

The bee hummingbird of Cuba is the smallest bird in the world.

An ostrich can run up to 43mph (70 km/h).

An annoyed camel will spit at a person.

The world’s smallest dog is the Chihuahua, which means “tiny dog in the sky.”

Pea crabs (the size of a pea) are the smallest crabs in the world.

75% of wild birds die before they are 6 months old.

The pig is rated the fourth most intelligent animal but are mentioned only twice in the Bible

Sheep are mentioned 45 times and goats 88 times in the Bible. Dogs are mentioned 14 times and lions 89 times, but
domestic cats are not mentioned.

Pork is the world’s most widely-eaten meat.

In Denmark there are twice as many pigs as people.

Dinosaurs did not eat grass: there weren’t any at that time.

The coyote is a member of the dog family and its scientific name, “canis latrans” means barking dog.

A giraffe can clean its ears with its 50cm (20 in) tongue.

A group of geese on the ground is a gaggle – a group of geese in the air is a skein. More animal collective nouns

The South American giant anteater eats more than 30,000 ants a day.

It is impossible to out-swim a shark – sharks reach speeds of 44 mph (70 km/h). Humans can run about 21 mph (35 km/h).

The sailfish is the fastest swimmer, reaching 68 mph (109 km/h), although a black marlin has been clocked at 80 mph (128 km/h).

The slowest fish is the Sea Horse, which moves along at about 0.01 mph (0.016 km/h).

Dolphins can reach 37 mph (60 km/h).

Of the 650 types of leeches, only the Hirudo medicinalis is used for medical treatments.

The heart of a blue whale is the size of a small car.

The tongue of a blue whale is as long as an elephant.

A blue whale weighs as much as 40 rhinos.

The eel is the only fish in the world that spawns in the middle of an ocean but spends its adult lives in rivers.

The scales of a crocodile are made of ceratin, the same substance that hooves and fingernails are made of.

A crocodile’s tongue is attached to the roof of its mouth and cannot move it.

A snail has two pairs of tentacles on its head. One pair is longer than the other and houses the eyes. The shorter pair is used for smelling and feeling its way around. (Some snail species have only one pair of tentacles, thus they have just one eye.)

The heaviest crustacean ever found was a lobster weighing 42 lb (19 kg), caught in 1934.

The largest jellyfish ever caught measured 7’6″ (2,3 m) across the bell with a tentacle of 120 ft (36 m) long.

The largest giant squid ever recorded was captured in the North Atlantic in 1878. It weighed 4 tons. Its tentacles measured 10 m (35 ft) long.

The giant squid has the biggest eyes of any animal: its eyes measure 16 inches (40 cm) in diameter.

Domestic cats purr at about 26 cycles per second, the same frequency as an idling diesel engine.

Sharks are immune to almost all known diseases.

Sharks and rays also share the same kind of skin: instead of scales, they have small tooth-like spikes called denticles. The spikes are so sharp that shark skin has long been used as sandpaper.

Animals also are either right-handed or left-handed. Polar bears are left-handed – and so is Kermit the Frog.

There are 701 types of pure breed dogs. There are about 54 million dogs in the US, and Paris is said to have more dogs than people.

Some bird species, usually flightless birds, have only a lower eyelid, whereas pigeons use upper and lower lids to blink.

Fish and insects do not have eyelids – their eyes are protected by a hardened lens.

Flatfish (halibut, flounder, turbot, and sole) hatch like any other “normal” fish. As they grow, they turn sideways and one eye moves around so they have two eyes on the side that faces up.

Measured in straight flight, the spine-tailed swift is the fastest bird. It flies 106 mph (170 km/h). Second fastest is the Frigate, which reaches 94 mph (150 km/h).

Millions of trees are accidentally planted by squirrels who bury nuts and then forget where they hid them.

There are more than 150 million sheep in Australia, a nation of 21 million people.

New Zealand is home to 4 million people and 70 million sheep.

 source : http://didyouknow.org/fastfacts/animals/

sports facts

Fishing is the biggest participant sports in the world.

Football (soccer) is the most attended or watched sport in the world.

Boxing became a legal sport in 1901.

More than 100 million people hold hunting licenses.

Jean Genevieve Garnerin was the first female parachutists, jumping from a hot air balloon in 1799.

In 1975 Junko Tabei from Japan became the first woman to reach the top of Everest.

The record for the most Olympic medals ever won is held by Soviet gymnast Larissa Latynina. Competing in three Olympics, between 1956 and 1964, she won 18 medals.

The record for the most major league baseball career innings is held by Cy Young, with 7,356 innings.

The first instance of global electronic communications took place in 1871 when news of the Derby winner was telegraphed from London to Calcutta in under 5 minutes.

In 1898, one of the first programs to be broadcasted on radio was a yacht race that took place in British waters.

Sports command the biggest television audiences, led by the summer Olympics, World Cup Football and Formula One racing.

Gymnasiums were introduced in 900BC and Greek athletes practiced in the nude to the accompaniment of music. They also performed naked at the Olympic Games.

The very first Olympic race, held in 776 BC, was won by Corubus, a chef.

The first modern Olympic Games were held in Athens, Greece in 1896. There were 311 male but no female competitors.

In his time, Michael Schumacher was the highest paid sportsman, ahead of Tiger Woods and Arnold Palmer. (Not including sponsorship endorsements.)

The high jump method of jumping head first and landing on the back is called the Fosbury Flop.

The Major League Baseball teams use about 850,000 balls per season.

About 42,000 tennis balls are used in the plus-minus 650 matches in the Wimbledon Championship.

The longest tennis match took place at Wimbledon 2010 when John Isner of the United States beat Nicolas Mahut of France 6-4, 3-6, 6-7 (7), 7-6 (3), 70-68 in a match that lasted 11 hours and 5 minutes, played over 3 days, June 22, 23 and 24.

A baseball ball has exactly 108 stitches, a cricket ball has between 65 and 70 stitches.

A soccer ball is made up of 32 leather panels, held together by 642 stitches.

Basketball and rugby balls are made from synthetic material. Earlier, pigs’ bladders were used as rugby balls.

The baseball home plate is 17 inches wide.

The very first motor car land speed record was set by Ferdinand Verbiest.

The record for the most NASCAR wins is held by Richard Petty: 200 wins (and 7 championships).

Golf the only sport played on the moon – on 6 February 1971 Alan Shepard hit a golf ball.

Bill Klem served the most seasons as major league umpire – 37 years, starting in 1905. He also officiated 18 World Series.

The oldest continuous trophy in sports is the America’s Cup. It started in 1851, with Americans winning for a straight 132 years until Australia took the Cup in 1983.

Volleyball was invented by William George Morgan of Holyoke, Massachusetts in 1895.

A badminton shuttle easily travels 180 km/h (112 mph).

Ferenc Szisz from Romania, driving a Renault, won the first Formula One Grand Prix held at Le Mans, France in 1906.

 source : http://didyouknow.org/fastfacts/sports/

facts about our body

The length from your wrist to your elbow is the same as the length of your foot.

Your heart beats 101,000 times a day. During your lifetime it will beat about 3 billion times and pump about 400 million litres (800 million pints) of blood.

It is impossible to lick your elbow. Well, for almost everyone… but a few can.

Your mouth produces 1 litre (1.8 pints) of saliva a day.

The human head contains 22 bones. More on the head and brains

On average, you breathe 23,000 times a day.

Breathing generates about 0.6g of CO2 every minute.

On average, people can hold their breath for about one minute. The world record is 21 minutes 29 seconds, by David
Merlini.

On average, you speak almost 5,000 words a day – although almost 80% of speaking is self-talk (talking to yourself).

Over the last 150 years the average height of people in industrialized nations increased by 10 cm (4 in).

In the 19th century, American men were the tallest in the world, averaging 1,71 metres (5’6″). Today, the average height for American men is 1,763 m (5 feet 9-and-half inches), compared to 1,815 m (5’10″) for Swedes, and 1,843 m (5’11″) for the Dutch, the tallest Caucasians.

The tallest nation in the world is the Watusis of Burundi: 1.98 m (6 feet 6 inches) tall.

If the amount of water in your body is reduced by just 1%, you’ll feel thirsty.

It is impossible to sneeze and keep one’s eyes open at the same time.

55% of people yawn within 5 minutes of seeing someone else yawn.

Hippocrates, the Father of Medicine, suggested that a woman could enlarge her bust line by singing loudly and often.

A person can live without food for about a month, but only about a week without water.

You’ll drink about 75,000 litres (20,000 gallons) of water in your lifetime.

After a certain period of growth, hair becomes dormant. That means that it is attached to the hair follicle until replaced
by new hair.

Hair on the head grows for between two and six years before being replaced. In the case of baldness, the dormant hair was not replaced with new hair.

Men loose about 40 hairs a day. Women loose about 70 hairs a day.

In the Middle Ages the length from the tip of the middle finger to the elbow was called an ell.

A person remains conscious for eight seconds after being decapitated.

The first successful human sex change took place in 1950 when Danish doctor Christian Hamburger operated on New Yorker George Jorgensen, who became Christine Jorgensen.

The muscle that lets your eye blink is the fastest muscle in your body. It allows you to blink 5 times a second.

On average, you blink 15 000 times a day. Women blink twice as much as men.

A typical athlete’s heart churns out 25 to 30 litres (up to 8 gallons) of blood per minute.

We have four basic tastes plus umami. The salt and sweet taste buds are at the tip of the tongue, bitter at the base, and sour along the sides; umami is a mixture of tastes sensed along the center of the tongue.

Not all our taste buds are on our tongue; about 10% are on the palette and the cheeks.

Unless food is mixed with saliva you cannot taste it.

The liver is the largest of the body’s internal organs. The skin is the body’s largest organ.

On average a hiccup lasts 5 minutes.

Fingernails grow nearly 4 times faster than toenails.

Your middle fingernail grows the fastest.

Your finger nails grow at 1 nanometre per second (0.000 000 001 m/s). Your hair grows at 4 nanometres per second (0.000 000 004 m/s).

It takes about 3 months for the transplanted hair to start growing again.

About 13% of people are left-handed. Up from 11% in the past.

In 1900, a person could expect to live to be 47. Today, the average life expectancy for men and women in developed countries is longer than 70 years.

A newborn baby’s head accounts for one-quarter of its weight.

King Henry I, who ruled in the England in the 12th century, standardized the yard as the distance from the thumb of his outstretched arm to his nose.

The bones in your body are not white – they range in color from beige to light brown. The bones you see in museums are white because they have been boiled and cleaned.

Our eyes are always the same size from birth.

Every person has a unique tongue print.

If all your DNA is stretched out, it would reach to the moon 6,000 times.

Approximately two-thirds of a person’s body weight is water. Blood is 92% water. The brain is 75% water and muscles are 75% water.

The colored part of the eye is called the iris. Behind the iris is the soft, rubbery lens which focuses the light on to a layer, called the retina, in the back of the eye. The retina contains about 125 million rods and 7 million cones. The rods pick up shades of gray and help us see in dim light. The cones work best in bright light to pick up colors.

We actually do not see with our eyes – we see with our brains. The eyes basically are the cameras of the brain. 

source : http://didyouknow.org/fastfacts/body/

earthquake facts

An earthquake is caused by a sudden slip on a fault. A fault is a fracture in the crust of the earth along which rocks on one side have moved relative to those on the other side. Stresses in the earth’s outer layer push the sides of the fault together, pressure builds up and the rocks slip suddenly, releasing energy in waves that travel through the rock to cause the shaking that we feel during an earthquake.

Earthquakes tend to be concentrated in narrow zones. There are 7 major crustal plates on earth, about 50 miles (80 km) thick, all in constant motion relative to one another, moving at the speed at which your fingernail grows, at between 10 and 130 mm (from less than one half to 5 inches) per year.

It is estimated that there are several million earthquakes in the world each year. Many of these earthquakes go undetected because they occur in remote areas, mostly under the sea, or have very small magnitudes. The USGS Earthquake Info Center locates about 20,000 earthquakes each year (about 50 per day). On average, about 60 earthquakes per year are classified as significant, with up to 19 classified as major. A significant earthquake is one of magnitude 6.5 or higher or one of lesser magnitude that causes casualties or considerable damage. Major earthquakes have a magnitude larger than 7.0.

In August 1999, an earthquake registering 7.4 on the open ended Richter Scale hit Turkey, killing more than 15,000 people. The next month, an earthquake registering 7.6 hit Taiwan. Later the same month, an earthquake registering 7.4 hit Mexico. In November, Turkey was hit again by an earthquake that registered 7.2.

Large earthquakes that originate from the sea bed result in tsunamis, causing huge waves to travel 500 mph (800 km/h) or more toward coasts. In 2004, the largest ever such tsunami killed more than 227,000 people in 14 countries along the Indian Ocean. It was estimated to have released more energy than 20,000 atomic bombs.

On January 12, 2010 an earthquake of magnitude 7.0 occurred 10 miles off the coast from Port-Au-Prince, Haiti, killing more than 200,000 people. The earthquake did not, however, came as a surprise to seismologists who predicted the fault slip just a week earlier. Governments and people often ignore the predictions of earthquakes.

The largest earthquake ever recorded occurred in Chile in 1960: it had a magnitude of 9.5. See the list of largest and deadliest earthquakes.

There are 2 basic types of earthquakes. A strike-slip earthquake occurs when the rock on one side of a fault slides horizontally past the other. In a dip-slip earthquake, the fault is at an angle to the surface of the earth and the movement of the rock is up or down.

Did you know? There are more earthquakes in Alaska than in California.

source : http://didyouknow.org/earthquakes/