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Imperial and metric system facts lost in history
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There are two measurement systems used in the world today: the imperial system (also known as the English system) and the metric system. The imperial system was developed in England hundreds of years ago and was brought to the the United States by the colonists. The metric system is the accepted measurement system used in most countries of the world. It is a system based on multiples of 10. The metric system was developed in France around 1790 and has been revised several times. Its official name today is the International System of Units or SI Units for short. Both systems have come a long way since there conception. Here are some noteworthy facts about both, which may have been "lost" in history, but are still worth mentioning today. Base u [ ... ]
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68 |
bio_man |
One day ago |
Top 5 Interesting Math Facts You Never Knew
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1) Roman Numeral IVAlthough the Roman numeral for the number 4 has always been taught to have been "IV," according to historians, the ancient Romans probably used "IIII" most of the time. This is partially backed up by the fact that early grandfather clocks displayed IIII for the number 4 instead of IV. Early clockmakers apparently thought that the IIII balanced out the VIII (used for the number 8) on the clock face and that it just looked better. 2) Base 60The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero." 3) Fraction BarThe Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole. It wasn't until later in h [ ... ]
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111 |
bio_man |
2 days ago |
Eyeless fish
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 The Mexican tetra ( Astyanax mexicanus) is a blind, freshwater cave fish native to central and eastern parts of Mexico. Growing to a maximum total length of 12 cm (4.7 in), this species is notable for having no eyes or pigment; it has a pinkish-white color to its body (resembling an albino). The Mexican tetra spends most of its time in midlevel water above the rocky and sandy bottoms of pools and backwaters of creeks and rivers of its native environment. Coming from a subtropical climate, it prefers water with 6.5–8 pH and a temperature range of 20 to 25 °C (68 to 77 °F). In the winter, some populations migrates to warmer waters. Its natural diet consists of crustaceans, insects, and annelids. Given their peaceful nature, this species is popu [ ... ]
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731 |
bio_man |
A month ago |
Nine longest words in the English language
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Want to better your vocabulary? Try pronouncing these words on your own, then attempt to use at least one in your next conversation! Pneumonoultramicroscopicsilic ovolcanoconiosis – 45 letters- A lung disease caused by breathing in volcanic dust.
Supercalifragilisticexpialido cious – 34 letters- Meaning "wonderful", from song of this title in the movie Mary Poppins.
Floccinaucinihilipilification – 29 letters- Meaning "the action or habit of estimating as worthless".
Trinitrophenylmethylnitramine – 29 letters- A chemical compound used as a detonator in shells.
Antidisestablishmentarianism – 28 letters- Meaning "opposition to the disestablishment of the Church of England".
Electroencephalographically – 27 lettersMicrospectrophotometr [ ... ]
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3299 |
bio_man |
3 months ago |
Why electronics have become inexpensive
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One-time use technology or throw-away electronics are becoming increasingly popular with consumers and product manufacturers. Apart from the disposable cameras offered in the 1980s and into the late 90s, tech-based companies could rarely offer such convenience due to the cost of certain parts required. The main reason why companies can now offer inexpensive products, including smartphones and computers, without compromising on modern technology or quality is due to the wide-spread production and availability of transistors – a major component of computers or any microprocessor (shown above). A comparison of laptops prices. Left: Macintosh Portable M5120 [1989] Right: Typical ASUS laptop sold todayA transistor is simply an on/off switch made [ ... ]
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3239 |
bio_man |
4 months ago |
The coconut crab
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The coconut crab (Birgus latro) is a species of terrestrial hermit crabs that's known for the largest land-living arthropod in the world, weighing up to 4.1 kg (9.0 lb). It is found on islands across the Indian Ocean and parts of the Pacific Ocean, mirroring the distribution of the coconut palm. Like other hermit crabs, juvenile coconut crabs use empty gastropod shells for protection, but the adults develop a tough exoskeleton on their abdomen and stop carrying a shell. Coconut crabs have evolved organs known as branchiostegal lungs, which are used instead of the vestigial gills for breathing. They cannot swim, and will drown if immersed in water for long. They have also developed an acute sense of smell, which has evolved convergently with [ ... ]
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984 |
bio_man |
5 months ago |
Wolf-like, fox-like, dog-like mammal
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The maned wolf ( Chrysocyon brachyurus) is the largest canid found in the grasslands of southern Brazil. Its markings resemble those of foxes and wolves, yet it's neither related to wolves nor foxes despite its appearance and name, but is actually closer to dogs. And, unlike other large canids, the maned wolf does not form packs. It hunts alone, usually between sundown and midnight, and kills its prey by biting on the neck or back. Interestingly, a large fraction of its diet (over 50%, according to some studies) consists of vegetable matter, including sugarcane, tubers, and fruit; this is unusual for canids. The maned wolf is generally shy and flees when alarmed by humans, and it poses little direct threat to humans. Luckily, the animal is w [ ... ]
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2038 |
bio_man |
8 months ago |
Poison dart frog
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The poison dart frog is the common name given to the most poisonous animals on Earth. Native to Central and South America, these species of frogs (family: Dendrobatidae) produce several lethal toxins that are capable of killing a human or other large animal with just 2 micrograms (μg). In other words, one drop of their venom could be powerful enough to kill 8000 people. The most toxic of poison dart frog species is Phyllobates terribilis. Unlike snakes, dart frogs do not synthesize their poisons, but sequester the chemicals they consume from arthropod prey, such as ants, centipedes and mites. This is why in captivity, they produce far less poison than wild frogs due to their change in diet. What makes these frogs immune to their own poison i [ ... ]
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1180 |
bio_man |
9 months ago |
Chicken egg colours explained
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It's a common knowledge that different breeds of chickens lay different colored eggs. Here I'll explain what chemicals and conditions give rise to these differences. White eggsAll eggshells are made of calcium carbonate and the white ones have no pigment added.Brown eggsThe brown colour is caused by protoporphyrin IX, from the hen's haemoglobin, and is coated on the outside of the egg as it moves through the oviduct.Blue eggsBlue eggshells have the pigment oocyanin, which does permeate the shell, so the blue coloring will be all the way through.Green eggsIf a brown layer and a blue layer are crossbred, chances are you will get a green egg when the protoporphyrin IX layer is deposited over the blue oocyanin shell.Pink eggsThe pinkish tint [ ... ]
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1092 |
bio_man |
11 months ago |
These bite-size fruits look like tiny watermelons
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Melothria scabra is a species of cucurbitaceous vine grown for its edible fruit, known as cucamelon. Cucamelons are about the size of grapes and taste like cucumbers, they are notable for their sour aftertaste that comes from the skin. The M. scabra plant is native to Mexico and Central America, where it is called sandíita (little watermelon). It is believed to have been a domesticated crop before western contact began. If you happen to get your hands on these tiny melons, apparently they are terrific in stir-fries; they can be pickled just like French gherkins, eaten raw in salads or put up like Polish dill pickles. They also can be chopped and added to salsas for extra texture and flavor. [ ... ]
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863 |
bio_man |
A year ago |
Why do we hiccup?
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A hiccup is an involuntary spasm of the diaphragm that typically repeats several times a minute. The sudden rush of air into the lungs that's created by each spasm causes the glottis to close, creating the "hic" noise. A bout of hiccups generally resolves by itself, although many home remedies are in circulation to shorten the duration. The medical term for hiccuping is singultus. While many cases develop spontaneously, hiccups are known to develop often in specific situations, such as eating too quickly, taking a cold drink while eating a hot meal, eating very hot or spicy food, laughing vigorously or coughing, or drinking an excess of an alcoholic beverage. Hiccups may be caused by pressure to the phrenic nerve (located in the neck regi [ ... ]
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840 |
bio_man |
A year ago |
Are you a 'supertaster'?
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A supertaster is a individual who lives in a more intense taste world because they have up to twice as many taste buds than the average person. Among individuals of European descent, it is estimated that about 25% of the population are supertasters. The evolutionary advantage to supertasting is unclear. In some environments, heightened taste response, particularly to bitter plant alkaloids, would represent an important advantage. However, other environments, increased response to bitter may have limited the range palatable goods. In our modern energy rich environment, supertasting may be cardioprotective, due to decreased liking and intake of fat, but may increase cancer risk via deceased vegetable intake. It may be a cause of picky eating [ ... ]
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762 |
bio_man |
A year ago |
One of the world's largest insects
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If you're not an insect lover, this is your final chance to turn your head!The giant Malaysian katydid ( Macrolyristes corporalis) is one of the largest insects in the world, with their bodies growing to 15 cm (6 inches) long with a 25 cm (10 inch) long wingspan. Though the last thing you want to hear is that this giant insect is carnivorous, they pose absolutely no threat to humans (aside from haunting your dreams, of course). Relatively speaking, the males of this species have the largest testes of any known animal at 14% of their body weight. If humans had the same ratio, a 91 kg (200 lb) man would have testes that weighed nearly 13 kg (28 pounds)! [ ... ]
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698 |
bio_man |
A year ago |
Can you spot the camouflaged frogmouth bird?
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The frogmouths are a group of nocturnal birds found from across India and southern Asia to Australia. They are named for their large flattened hooked bills and huge frog-like gape, which they use to take insects. The one's shown above are tawny frogmouths, and they exhibits one of the best examples of cryptic plumage and mimicry, which perch low on tree branches during the day camouflaged as part of the tree. Their silvery-grey plumage patterned with white, black, and brown streaks and spots allows them to freeze into the form of a broken tree branch and become practically invisible in broad daylight. The tawny frogmouth often chooses a broken part of a tree branch and perches upon it with its head thrust upwards at an acute angle using it [ ... ]
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708 |
bio_man |
A year ago |
Are human-chimpanzee hybrids possible?
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The idea that a chimpanzee and human can interbreed, forming a hypothetical hybrid species known as a humanzee, is not uncommon. Since chimpanzees and humans are closely related species (sharing 95% of their DNA sequence, and 98% of coding DNA sequences), it has lead to contested speculation that a hybrid is possible, though no specimen has ever been confirmed. While there is a commonality in gene sequence between us and chimpanzees, humans still have one fewer pair of chromosomes (46 chromosomes) than other apes (48 chromosomes). This makes conception between the two species naturally impossible. However, a different numbers of chromosomes is not an absolute barrier to hybridization. Similar mismatches are relatively common in existing spec [ ... ]
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713 |
bio_man |
A year ago |
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