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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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2405 |
bio_man |
5 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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1503 |
bio_man |
5 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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1478 |
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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1170 |
bio_man |
6 years 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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1167 |
bio_man |
6 years 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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1436 |
bio_man |
6 years 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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1175 |
bio_man |
6 years 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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1040 |
bio_man |
6 years 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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1238 |
bio_man |
6 years ago |
How loud is a rooster's crow?
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Loud enough to deafen you if you stand too close. Researchers have found that roosters produces 1 to 2 second crows that can get as loud as 143 decibels. This is equivalent to standing 15 meters away from a jet taking off. But if that's the case, how do roosters and surrounding chickens tolerate this noise? Researchers have found that when a rooster’s beak is fully open, as it is when crowing, a quarter of the ear canal completely closes and soft tissue covers 50% of the eardrum. This means roosters aren’t capable of hearing their own crows at full strength. The intensity of a rooster’s crow diminishes greatly with distance, so it probably doesn’t cause significant hearing loss in nearby hens. Interestingly, unlike mammals, birds ca ...
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1103 |
bio_man |
6 years ago |
What color is a toucan's skull?
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Well, obviously it's white, but take a look at its bill! The attractive 7.5-inch-long bill is possessed by both male and female toucans. Interestingly, they use them during a mating ritual, pitching fruit to one another, but has very limited use as an excavation tool. Toucans make their nests in tree hollows found in rain forest regions of Southern Mexico, Central and South America, and the Caribbean region to which they are native. ...
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1099 |
bio_man |
6 years ago |
What does a box and these fish have in common?
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Their name and shape!Ostraciidae is a family of squared, bony fish closely related to the pufferfishes and filefishes. Members of this family occur in a variety of different colors (e.g. right - Hawaiian Blue Boxfish, Ostracion meleagris and the Yellow Boxfish, Ostracion cubicus), and are notable for the hexagonal or "honeycomb" patterns on their skin. Boxfish swim in a rowing manner. Their hexagonal plate-like scales are fused together into a solid, triangular or box-like carapace, from which the fins, tail, eyes and mouth protrude. Because of these heavy armoured scales, Ostraciidae are limited to slow movements, but few other fish are able to eat the adults. Some boxfish also secrete poisons from their skin into the surrounding water, fu ...
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6161 |
bio_man |
6 years ago |
Confusing cat-like animal from Madagascar
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The fossa ( Cryptoprocta ferox) is carnivorous mammal endemic to Madagascar. It is a member of the Eupleridae, a family of carnivorans closely related to the mongoose family. Its classification has been controversial because its physical traits resemble those of cats, yet other traits suggest a close relationship with viverrids (e.g. bearcat). The fossa is the largest mammalian carnivore on the island of Madagascar and has been compared to a small cougar. Adults have a head-body length of 70–80 cm (28–31 in) and weigh between 5.5 and 8.6 kg (12 and 19 lb), with the males larger than the females. It has semi-retractable claws (meaning it can extend but not retract its claws fully) and flexible ankles that allow it to climb up and down tre ...
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6119 |
bio_man |
6 years ago |
What causes the rattle in a rattlesnake's tail?
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Rattlesnakes are a group of venomous snakes native to the Americas known for their loud rattling tail. The tip of their tail, known as the rattle (middle), vibrates to deter predators or serves as a warning to passers-by. The rattle is composed of a series of hollow, interlocked segments made of keratin, which are created by modifying the scales that cover the tip of the tail. The contraction of special "shaker" muscles in the tail causes these segments to vibrate against one another, making the rattling noise (which is amplified because the segments are hollow) in a behavior known as tail vibration. The muscles that cause the rattle to shake are some of the fastest known, firing 50 times per second on average, sustained for up to three hour ...
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5982 |
bio_man |
6 years ago |
Hammers are no match for this glass
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The tough-yet-fragile physical properties of the tadpole-shaped pieces of glass known as Prince Rupert’s drops have puzzled physicists for as long as, well, there have been physicists. Bash the head with a hammer, and a drop gets barely a scratch. But break off its thin tail, and it shatters into fine powder. Researchers long ago realized that the strength of the drops - named for Prince Rupert of Bavaria, who presented five of them to Britain’s King Charles II in 1660 - has something to do with stresses in the glass created when a drop is made by letting a blob of molten glass fall into water, so that it cools rapidly. Twenty years ago, a pair of researchers took high-speed video of a drop disintegrating showing that, when the tail is brok ...
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3831 |
bio_man |
6 years ago |
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