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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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1233 |
bio_man |
6 years 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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1224 |
bio_man |
6 years 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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1536 |
bio_man |
6 years 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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1552 |
bio_man |
6 years 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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2450 |
bio_man |
6 years 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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1714 |
bio_man |
6 years ago |
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 their 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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1371 |
bio_man |
5 years 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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2426 |
bio_man |
5 years 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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1285 |
bio_man |
5 years ago |
Where is our third eyelid?
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Some mammals, such as camels, polar bears, and seals, have full nictitating membranes. That is the transparent or translucent third eyelid that can be drawn across the eye for protection and to moisten it while maintaining visibility. In humans, the plica semilunaris (also known as the semilunar fold) and its associated muscles are thought to be homologous to the nictitating membranes seen in other animals. In most primate species, a plica semilunaris is present, but a fully developed nictitating membranes still exists in lemurs and lorisiform primates. Unlike the upper and lower eyelids, the nictitating membrane moves horizontally across the eyeball (shown below). In some diving animals, such as beavers and manatees, it moves across the e ...
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2653 |
bio_man |
5 years ago |
How much of our lifetime do we spend peeing?
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Regardless of your size, men and women, big or small, all pee at the same average rate — between 1/3 and ½ ounces per second (10 ml to 15 ml per second). Since the mean urine quantity ranges between 1 to 2 quarts a day (1.4 L, on average), we are condemned to spend one to two full minutes peeing daily. The average lifespan in the United States today is 27,375 days. If we multiplying 27,375 days by 2 minutes per day peeing, that's 54,750 minutes, or 912.5 hours of your lifetime urinating. That also translates into roughly 38 days of your lifetime ...
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1411 |
bio_man |
4 years ago |
Most intelligent bird species
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Birds are very clever animals. They exhibit a wide range of smart behaviors, including good memories, extensive communication, planning for the future, and remembering the past. Some birds can solve problems, and others are capable of adapting to new environments and conditions. Experts often think of intelligence in terms of creative abilities used to solve problems. Some scientists believe that tool-using birds show such abilities. The woodpecker finch (first from left) of the Galapagos Islands, for example, has learned to use a cactus spine or small twig as a probe to remove carpenter bee larvae from their tunnels. The Egyptian vulture (second from left) uses rocks to break open ostrich eggs. Gulls learn to drop clams and turtles onto roc ...
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18289 |
bio_man |
3 years ago |
Fastest mammal in the sea
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Dall’s Porpoise are among the fastest swimmers of all cetaceans, which includes dolphins and whales. This porpoise swims at such high speeds – up to 56 km/h (35 mph) – that observers often see only the cone-shaped water spray kicked up by its head, rather than the porpoise itself. The Dall’s porpoise often playfully rides the waves rolling off the bows and sterns of boats. As it plays, it sometimes zigzags over the waves so vigorously that it unwittingly escapes the aim of harpooners poised on deck. Due to its athletic habits, this porpoise must eat a great deal of food – up to 15 kg (33 lb) a day. It feeds on small fish and various cephalopods, including squid, primarily at night. ...
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4362 |
bio_man |
2 years ago |
You've only ever seen one side of the moon
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Did you know that the Moon's rotation is locked to its orbit around Earth by a bulge of material under the Moon's surface? This material is denser than the rest of the Moon's surface material, and Earth's gravity pulls on it especially strongly. The side of the Moon containing the bulge always faces Earth. We call it the near side and we call the other side, which we never see from Earth, the far side. People often mistakenly use the term "dark side" when referring to the far side of the Moon, forgetting that the far side is fully illuminated by the Sun whenever we see a new moon from Earth. If we were to look from high above the Earth-Moon system, we would see the Moon rotate once per month with respect to the stars. This is its sidereal ro ...
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14018 |
bio_man |
2 years ago |
How does our vision compare to some animals?
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Do animals see the same way we do? Do some animals have better vision than humans? The senses of animals have evolved to give members of the species an optimum chance for survival. Here are a few examples: Some animals, such as cats, have a reflective surface ( tapetum) on the back of the eye behind the sensory receptors (left image above). When light first enters the eye, some light is detected by the sensory receptors. The light not detected by the sensory receptors continues onto the reflective surface at the back of the eye. This light is then reflected outward toward the sensory receptors, providing a second opportunity for detection. This feature produces two results. First, the outward reflection results in the shining of the cat's ey ...
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15016 |
Biology Forums |
2 years ago |
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