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learningabtsharks · 4 years

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The Anatomy of Sharks

Reproductive information will be in another post, hidden completely behind a cut.

Movement

Sharks are a cartilaginous fish, meaning their skeleton is entirely comprised of cartilage, not bone. Because of this, their skeleton is more light weight, making it easier to remain afloat. It also allows much more flexibility.

When it comes to the majority of fish, most use a swim bladder to remain buoyant. Sharks, however, do not have a swim bladder, this makes them heavier than water. Sharks use their large livers, fins, and the aforementioned cartilaginous skeletons.

Sharks use their fins to create dynamic lift, in a method similar to airplanes. (This means if they stop swimming, they stop floating.) Due to their bodies bulk and the size of their fins, this alone isn’t enough to keep them afloat.

Sharks also must use their massive, oil-filled livers. The oil in a sharks liver is called squalene, which is lighter than water. This increases the sharks buoyancy, enabling them to remain afloat.

Sharks skin is made up of many platelike scales, called placoid scales, or dermal denticles. Placoid scales are v-shaped, which reduces drag and makes swimming more efficient. These denticles also prevent marine growth, such as algae and barnacles, due to the irregular surface. Female sharks skin is up to three times thicker than male sharks.

Gills

Sharks breathe through their gills, just as other fish do. They take in water through their mouth, which passes through their blood rich gills. Blood vessels extract oxygen from the water as it passes by. Carbon dioxide waste from their blood is expelled through the gill tissue as well.

Species that are less active when it comes to swimming use a method called buccal pumping.

Merriam-Webster says buccal means, “of, relating to, near, involving, or supplying a cheek”. LINK

Sharks that are not capable of buccal pumping use something called ram ventilation. (These sharks are called obligate ram ventilators.) These species swim at a quicker pace with their mouths open in order to pass water over their gills.

Sharks that are capable of buccal pumping pull water into their mouths via their cheek muscles, passing the oxygenated water they need over their gills without swimming.

Sharks who respire like this have spiracles, which are gill openings behind their eyes that enable them to take in the water they need. Like a snorkel.

Senses

The lateral line system is an organ that enables the majority of fish to detect minute vibrations in the water. In sharks, lateral line canals are just beneath the skin of its snout and along the sides of its body. Lateral line canals are full of tiny hair-like structures, as well as fluid. When vibrations reach the hair-like structures, they move, sending signals to the brain. These signals help the shark in pinpointing the placement of something else in the water.

This system also detects odor plumes, which are a complex structure created when odor molecules are released from their source and moved. This enables sharks to locate prey and other mates.

A sharks sense of smell and it’s lateral line are heavily intertwined. If their lateral line is inhibited somehow, they will find it difficult to detect odor plumes, even if their actual nose is perfectly fine.

The sharks nasal cavities have two openings, an entrance point for water, and an exit point for water. Sharks pull water into nasal sacs and over folds of tissue. A sharks nasal cavities are quite large, giving it more time to sort out the scents it picks up. The sharks brain will then analyze the smells, matching them to it’s prey, or even those of possible mates.

The lateral line of a shark could be considered an extension of the sharks ear, as both use hair cells to assist it in keeping it’s balance and are attuned to the frequencies one would associate with underwater sounds.

There are small openings on both sides of sharks heads, leading to the inner ear. The sharks ear is a group of ducts and sacs filled with endolymph, called a membranous labyrinth. Endolymph is simply what the liquid filling the ducts and sacs of the labyrinth is called, in sharks this is mainly sea water that enters through its ducts. These ducts are protected by the cartilaginous labyrinth surrounding it, a set of canals filled with fluid.

Through the endolymphatic ducts, is the sacculus, the lagena, and the utriculus. These are lined with the aforementioned hair cells, which detect vibrations in the water. For hearing, there is an even longer hair cell, called a klinocilium. This hair cell extends into something called a cupola. The cupola of a shark is slightly exposed, and jelly-like. Sound vibrations in the water cause the cupola to wiggle, which the klinocilium picks up on. The klinocilium transmits these signals to the brain.

The cartilaginous tubes in a sharks ear are only able to pick up vibrations that are parallel to it. However, there are three of them. Together, they detect vibration in all directions. As a shark loses balance, the fluid within its ears slows down. The hair-cells feel this, and transmit signals that enable the shark to correct it’s balance.

Sharks skin is highly sensitive

Sharks do not have color vision, but as far as fish go, their eyes are quite good. They’re still able to process focused images. Most fish have rod only retinas, made for low light levels. Sharks have both rods and cones, cones being the ones responsible in higher light levels. (It’s worth noting the light levels where both rods and cones are active are called, “Mesopic”.) This is distinctly similar to human eyes. The part of a sharks brain that coordinates movement in regards to visual input is similar in size to that of a humans.

While there are quite a few similarities, there are also a few glaring differences. For instance the presence of a reflective layer, called the tapetum lucidum, at the back of a sharks eye, which light bounces off of, allowing sharks to analyze the light twice over. This is especially helpful in lower light levels.

Another difference is the way our eyes focus light. While humans have muscles that control the shape of our lens to focus light, sharks have muscles that push and pull the retina. This manner of focusing light is quite similar to the focusing of a camera.

While all sharks have rods and cones, some have more rods, and some have more cones. Deep water species will have far more rod photoreceptors due to the low light conditions.

Sharks sense of taste isn’t nearly as adapted as all of their other senses, due to the fact it is not necessary for survival. Their taste buds are in their mouth, as opposed to ours, which are in our tongue. Sharks have many pressure sensitive nerves in their teeth.

On top of everything else, sharks are also capable of sensing minor electrical fields. Every living thing gives off a very small amount of electricity, via the brain, muscle movement, or even the heart beat.

Sharks have receptors all along their head and snout. The receptors are jelly-filled tubes that open on the surface of the skin, called the ampullae of Lorenzini. The jelly within the tube is highly conductive, and when it picks up on electricity, it transmits it to the bulb that is at the end of each tube. The electric signal activates nerves, and sends the resulting signal to the brain.

These sensors are so sensitive they can detect muscle contractions of prey, and it is theorized that sharks detect the earths geomagnetic field and use it to navigate in the open ocean. These electrosensors have a very minute range due to the incredibly weak electrical impulses of usual prey.

Sharks use this sense to locate prey that is hidden, or from far away. They pick up on the muscle contractions of other fish, like that of a fish that is wounded and struggling.

Diet

All sharks are carnivores, with one exception. This exception is the bonnethead shark, which is an omnivore.

When it comes to sharks, their hunting grounds, hunting methods, and diet all vary wildly. Their teeth match this variety.

A shark with flattened teeth, such as the horn shark or nurse shark, uses them to crush their food. The structure of the teeth make it easier to crush shells.

A shark with needle like teeth would be very effective at gripping more evasive prey.

The Great White Sharks lower teeth are pointed, while its upper teeth are triangular. Their teeth have serrated edges, enabling them to slice up their prey into fun-sized pieces

Sharks teeth are usually used for hooking prey, crushing, or slicing. Sharks bite force being as immense as it is, plus a lack of a tough jaw bone means that teeth often break off whilst feeding and other activities. These teeth are replaced by those in reserve rows.

Depending on the species, sharks can have up to fifty rows of teeth at a time. When a shark loses a tooth, its gums push forward the teeth in the reserve rows like a conveyor. A sharks tooth can be replaced in under two weeks.

In most species, the upper jaw is fully and firmly connected to the skull, and it is the lower jaw that moves. With sharks, that isn’t exactly the case. Sharks move their entire mouths to catch their prey. Not only can they move their lower jaw, they can move their upper as well.

There are sharks that are bottom feeders, and there are those that are filter feeders. There are those with incredibly specialized hunting methods, and those that eat just about anything.

Reproduction

LINK

LINKS

https://www.dcnanature.org/shark-biology/

https://science.jrank.org/pages/1246/Cartilaginous-Fish.html

https://www.fossilguy.com/gallery/vert/fish-shark/remnant.htm

https://www.sharks-world.com/why_do_sharks_have_cartilage/

https://www.sharksinfo.com/buoyancy.html

https://animals.mom.me/oily-liver-shark-work-7894.html

https://www.thoughtco.com/placoid-scales-definition-2291736

https://ocean.si.edu/ocean-life/sharks-rays/sharks

https://www.scientific.net/AMR.79-82.977

http://www.elasmo-research.org/education/topics/p_liver_size.htm

https://www.dkfindout.com/us/animals-and-nature/fish/how-fish-breathe/

https://www.livescience.com/34777-sharks-keep-swimming-or-die.html

https://www.merriam-webster.com/dictionary/buccal

https://poseidonsweb.com/how-fish-breathe-ram-ventilation-buccal-pumping/

https://www.sharksider.com/spiracles/

https://www.sharksinfo.com/lateral-line.html

https://www.britannica.com/science/lateral-line-system

https://www.annualreviews.org/doi/pdf/10.1146/annurev.en.37.010192.002445

https://www.pbs.org/kqed/oceanadventures/episodes/sharks/indepth-senses.html

https://www.sciencedaily.com/releases/2007/05/070529140610.htm

https://jeb.biologists.org/content/210/11/iii

https://www.sharksinfo.com/hearing.html

https://animals.howstuffworks.com/fish/sharks/shark-senses2.htm

https://www.ncbi.nlm.nih.gov/books/NBK10792/

https://www.epicdiving.com/shark-vision/

https://azretina.sites.arizona.edu/node/353

https://www.cis.rit.edu/people/faculty/montag/vandplite/pages/chap_9/ch9p1.html

https://www.enchantedlearning.com/subjects/sharks/anatomy/Senses.shtml

https://www.shark.ch/Information/Senses/index.html

https://www.sharktrust.org/shark-senses

https://phys.org/news/2018-02-sharks-animals-evolved-electroreception-theirprey.html

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1578252/

https://www.discovermagazine.com/planet-earth/these-first-known-omnivore-sharks-eat-seagrass

https://www.sharksinfo.com/jaw.html

https://www.bradenriverdentist.com/a-guide-to-shark-teeth/

https://cimioutdoored.org/shark-teeth/

https://animals.howstuffworks.com/fish/sharks/shark4.htm

#shark blogging #sharks #shark #shark profile

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ahkaraii · 5 years

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I have a challenge for you. Can you make Kisame's design (blue skin, massive size, gills, ALL OF IT)) probable using your real world medical knowledge? Like what would this poor guy need to have in order to look like this naturally?

I don’t think I can make it plausible XD But I can certainly try to explain the etiology of a couple of his most standout traits, and maybe go into a bit of shark anatomy?

So in humans, blue skin can either indicate cyanosis (low blood oxygen will tinge the skin pale bluish-purple) or argyria, a condition where your skin, mucous membranes, and internal organs all gain a pale purple-grey colour due to chronic silver ingestion. Maybe the Hoshikagi children are exposed to silver contents as children to give them that curious coloration? It isn’t actually that crazy of a thought: here in mexican public hospitals, we give silver nitrate eye drops to prevent gonorrhoeal conjunctivitis in newborns when we run out of erythromycin (which is depressingly more often than you’d expect :V) So maybe the Hoshikagi clan historically started giving it prophylactically to prevent newborn blindness, but its chronic overuse caused it to become their clan trait, since it turned their sclera and skin blue...? Things to think about.

Speaking of sclera, Kisame’s is black with a colourless white iris. Actual humans can get their sclera to be black as a type of tattoo! You insert ink into the virtual space between the conjunctiva and slcera, which then quickly spreads throughout the whole “white” part of the eye. Maybe the Hoshigaki also inject black ink into their kid’s eyes when they’re born. (Hah...maybe their avid needle use and consequent high rate of eye infections is what caused them to start using the silver nitrate drops prophylactically in the first place? Though this order is less likely, as eye infection due to unsterile needle practice is more likely to be Staphyloccocus aureus or some other skin-dwelling bacteria than the vertically transmitted mother-to-child gonohrrea or chlamydia. Hum.)

Thinking about ink, maybe Kisame’s three “gill-like” lines below his eyes are tattoos, instead of functional gills. His shoulder gills are likewise tattoos. Instead of helping him breath air (because he wears clothes over them and he’d quickly suffocate if they were functional), maybe they help the Hoshigaki mold nature chakra?? It would help explain why they characteristically have such massive chakra stores despite not being jinchuuriki (or Uzumaki). Maybe the ink is special...?

Either that, or they really are supplementary gills, which makes their placement kinda odd but hey, this is Naruto world, who needs logic. Shark’s gills and how they oxygenate their circulating blood is interesting, and I’d need to research more to understand how that happens. In humans, our lungs -- specifically our alveoli -- are composed of type 1 and type 2 pneumocytes, the latter of which forms a special membrane that permits the passive diffusion of oxygen from the air into our blood cells, and vise versa for carbon dioxide. I imagine something similar must be happening with the histology of gill cells and the underlying capillary blood vessels, but, again, I’d have to research it...

I just discovered actual shark skin is composed of a genetic variation of teeth, which is fascinating. I already knew that teeth and skin come from the ectodermal germ layer -- during embryogenesis, we actually form a “sandwhich” of three distinct layers of cells, called endo-, ecto-, and mesodermal, respectively. Endodermal layer produces some internal organs, like the digestive system, the lungs, and the genitourinary system. Mesoderm forms muscles and erythrocites. And the ectoderm produces skin, teeth, nails, and brain cells. (So yeah, your skin and neurons arise from the same progenitor germ layer, haha.)

((Random fun fact! Teratomas, which are a cancer produced from germ cells, produce tissue from one or more germ layers due to this fact. That’s how you can get abdominal masses that contain teeth and hair and skin and neurons.))

ANYWAY back to shark skin. Turns out scientists recently discovered shark skin’s characteristic sandpaper feel and decreased drag in the water is because their skin is composed of rows of dermal denticle-like plates, with an outer layer of enamel, dentine and inner layer of pulp. Maybe the Hoshigaki have a genetic quirk during embryogenesis that directs the ectodermal germ cell layer to develop this kind of “skin” instead of the usual human one. Lil sharp babes.

His massive size is probably a combination of genetics, protein-rich diet, and muscle-building exercise. I know some folks have a naturally more athletic build because they have different kinds of muscle fibers. In particular, type 2 muscle fibers permit more explosive, high-intensity movements, and have a tendency towards hypertrophy (they’re popularly called “fast-twitch” muscle fibers). Type 1, or slow-twitch muscle fibers, are more handy for endurance. The difference between them lies primarily with the amount of energy-producing mitochondria, the availability of intracellular glycogen, and the activity rate of an enzyme called ATPase.

But yeah, I’m sure there’s loads of cool theories one could come up with to explain Kisame’s characteristic design that go beyond “genetic quirks!” and “neonatal tattooing!” xD What are your thoughts, friends?

#ask responses #meta #xxsurvivalistxx

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autodidact-adventures · 6 years

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Marine Life: Stingrays

Kimgdom: Animalia

Phylum: Chordata (animals with a notochord for at least part of their life; a notochord is a flexible rod made out of a material similar to cartilage).

Subphylum: Vertebrata

Class: Chondrichthyes (cartilaginous fishes)

Subclass: Elasmobranchii (this subclass includes sharks, rays, skates and sawfish).

Superorder: Batoidea (rays)

Order: Myliobatiformes (one of four orders of batoids).

Suborder: Myliobatoidei (one of three suborders).

There are eight families of stingrays.

Most stingrays have a barbed stinger (or more than one) on their tail, modified from dermal denticles. It can be up to 35cm long, and is used in self-defence. The underside of the stinger has two grooves with venom glands. The actual venom is concentrated in the integumentary sheath – a thin layer of skin that covers the stinger. There are a few stingray species (e.g. the manta & porcupine rays) that don't have stingers.

Stingrays are commonly found in tropical & subtropical coastal waters, all around the world. Some are found in warmer temperate oceans, and others in the deep ocean.

The river stingrays (family Potamotyrgonidae) are only found in fresh water; so are some of the whiptail stingrays (family Dasyatidae).

Most stingrays live in the 2nd-lowest zone of the water column (they are demersal). However, some of them live in the pelagic zone (they are pelagic), such as the pelagic stingray, and the eagle rays (family Myliobatidae).

Behaviour

Because they're so flat, stingrays can hide very easily – they agitate the sand and then hide in it. Their eyes are on top of their bodies, and their mouths are on the underside. Therefore, as they actually can't see their prey, they use smell and their ampullae of Lorenzini (electoreceptors similar to what sharks have) instead.

When feeding, stingrays settle on the sea floor, with only their eyes & tails visible. Their favourite feeding grounds are coral reefs, and during high tide they share them with sharks.

Reproduction

For some stingray species (e.g. the round stingray or Urobatis halleri) use their ampullae of Lorenzini to sense certain electrical signals that mature females give off. When he courts a female, he follows her closely while biting at her pectoral disc. Then, he places one of his two claspers into the female's valve.

Female stingrays bear their young in litters of 5-13 – they are ovoviviparous, which means that the embryos develop in eggs, and stay in their mother's body until they're ready to hatch. The eggs stay in the stingray's womb, and there is no placenta. The embryos absorb nutrients from a yolk sac. After the yolk sac has been depleted, the mother provides uterine “milk”.

Female rays can store sperm for two years and not give birth until they decide the time is right.

Diet

Various stringrays have various ways of eating. Some have specialized jaws that they use to crush hard mollusc shells. Some have cephalic lobes (a type of external mouth structure) to guide plankton into the oral cavity.

Stingrays that reside on the sea floor (they are benthic) use a strategy called tenting. They wait until the prey comes close, then press their pectoral fins against the substrate and raise their head. This creates a suction force that pulls the prey under their body.

Stingrays have a wide variety of colours & patterns on their dorsal surface: this helps them to camouflages themselves in the sand. Some stingrays can change colour over the course of several days, in order to adjust to a new habitat.

For most stingrays, their main foods are molluscs, crustaceans, and occasionally small fish. In the Amazon, freshwater stingrays eat insects, breaking down the exoskeletons with mammal-like chewing motions. Some large pelagic rays (such as the manta ray) use ram feeding to eat huge amounts of plankton; some have been seen swimming in acrobatic patterns through plankton patches.

Stingrays and Humans

Stingrays can be caught with fishing lines or spears. Dried wings are the most common stingray dish around the world, but there are many different recipes. In Mayalsia & Singapore, the stingray is usually grilled over charcoal, then served with spicy sambal sauce.

The flaps (wings) are usually the most prized part of the stingray, as well as the cheek (area surrounding the eyes) and the liver. The rest is considered to be too rubbery to eat.

Stingrays are usually docile and curious, not aggressive. They will usually flee any disturbance, but sometimes they brush their fins past a new object they've encountered. However, some of the larger stingray species are more aggressive. Their stinger, which they use for defence, can cause injury or even death.

Divers and snorkellers can find stingrays in shallow, sandy waters, especially when the water is warm. (Swimmers usually can't see them.) There are sites where humans can swim with stingrays and even hand-feed them, such as in the Cayman Islands, Belize, many Tahitian island resorts, and the Caribbean island of Antigua.

Because stingray skin is hard and rough, it is often used for the under layer of the ito (cord/leather wrap) for Japanese swords. Some museums show arrowheads & spears made from stingers, used in places like Micronesia.

Stingray Families

Butterfly rays – Gymnuridae

Deepwater stingrays – Plesiobatidae

Eagle rays – Myliobatidae

River stingrays – Potamotrygonidae

Round rays – Urotrygonidae

Sixgill stingrays – Hexatrygonidae

Stingarees – Urolophidae

Whiptail stingrays – Dasyatidae

[Source]

#zoology #biology #marine life #stingrays

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actualnymph · 6 years

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wow…sharks have skin that’s made up of tiny teeth called dermal denticles and they’re “shaped like curved, grooved teeth and make the skin a very tough armor with a texture like sandpaper.” I fucking love sharks so much

#how fuckign hardcore im crying #t #sharks

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coyote-carnage · 7 years

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lithokitty hat auf dein Foto geantwortet: the boys are back in town

Please tell us about the big dude, he intrigues me!

That’s Emeron! He’s an obsidian Byranthian. Byranthians are large, territorial demons that exist between the 77th and 81st lines (deep; the Purgatorium is measured vertically, sea level is around the 45th line). Obsidians are the larger of the two subspecies, amethystines being the smaller. Aside from size, they are easily identified by their rough skin--made of dermal denticles--their aposematism, their quadrupedal gait, and their lack of eyes. They have the ability to spit gastric acid, made more dangerous by their consumption of sulfur during mating seasons. Though they typically walk on all fours, they are fully capable of standing or sitting upright.

They’re considered one of the more “primitive” of the Purgatorium species because of their lack of government, language, or unified identity. They communicate through hums, snorts, chirps, and clicks. However, they are highly sensitive to changes in climate and wartime, and will adjust accordingly and will even lend aid to constituents in a war. They have complex social groups called fleets that consist of 20 to 50 adults.

Emeron is extremely small for his kind (sizing up to 8′6″ standing upright, weighing in at 615 lbs), and was rejected by his fleet as a juvenile. Because of this, he had to escape the 77th line and move upward in order to eat and not get attacked by larger Byranthians. But because Byranthians are not adapted to hunting on the surface, he nearly starved. Etomane found him on a trade route and decided to temporarily take him in, nurse him back to health, then release him. Of course, Emeron became very attached to Etomane, and again Byranthians are territorial, so he refused to leave Etomane’s shop. And he’s been there ever since.

#replies #[shrugs]

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laramariesimons · 5 years

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Nature is nothing if not surprising. You could spend your whole life learning the wonders of wildflowers, migratory birds, or creatures of the seashore and still discover only a fraction of the things the living world has to offer. Though nature is fascinating in its own right, it can also teach us many ways of improving our own lives; indeed, it's been a constant source of inspiration for inventors. Some fashion designers and clothing manufacturers are now turning to nature for help in developing biomimetic clothing, which performs more effectively by mimicking the wonders of the biological world. Others are getting as far away from nature as possible with smart clothes, based on cutting-edge electronics and computing. Let's take a closer look at these two, radically different ways of creating hi-tech clothes!

Photo: Now that's what I call a fur coat. Can animals like these musk oxen inspire us to design warmer human clothes? That's what biomimetics is all about. Photo of musk oxen on Nunivak Island by courtesy of US Fish & Wildlife Service.

Biomimetic clothing—learning lessons from nature?

When a German engineer called Otto Lilienthal (1848–1896) strapped wings to his arms and jumped off a hill in an attempt to fly, many people thought he was crazy. They had a point: he did, eventually, kill himself trying to fly like the birds. But his pioneering glider experiments inspired the Wright brothers to develop their engine-powered airplanes in the early 20th century and played a hugely important part in the history of human flight.

Photo: Reinventing flight: Biomimetics doesn't always work. To begin with, humans tried to fly by flapping wings like birds. People only successfully took to the air when they thought about the problem a different way and stopped copying nature so literally. The Wright brothers making their historic powered flight at Kitty Hawk, North Carolina in December 1903. Photo courtesy of Wikimedia Commons.

Lilienthal the "birdman" is only one example of how nature has inspired inventors. How about the story of British engineer Marc Isambard Brunel (1769–1845), father of famous engineer Isambard Kingdom Brunel (1806–1859), who invented a new way of digging tunnels underwater after watching a worm burrowing through the wooden planks of a ship? Or what about Swiss engineer George de Mestral (1907–1990), who invented the amazingly useful fastening material called VELCRO® after seeing how stray burrs from the burdock plant stuck like glue to the fur of his dog.

Photo: VELCRO®: George de Mestral's amazingly useful two-part textile fastener was directly inspired by nature. This is a diagram of the hook-and-loop mechanism sketched in his original patent US Patent 3,009,235: Separable fastening device (filed 1958, granted 1961). Artwork courtesy of US Patent and Trademark Office.

Before synthetic textiles such as nylon and polyester were developed in the 20th century, people only ever wore clothes made from natural materials like leather, wool, silk, and cotton. Now synthetic fibers have proved useful in all kinds of ways. Nylon, for example, is strong, hard-wearing, easy to clean, and quick-drying—so it's a popular choice for outdoor clothing. But wearing simple, ordinary nylon is a bit like wrapping yourself up in a plastic bag. Very quickly, you start to sweat—and on a hot, rainy summer's day you can easily become wetter through perspiration than you would have done just by letting the rain in. Natural materials like leather are much "smarter" than this: they let perspiration flow out but stop rain leaking in at the same time. What makes us think our synthetic materials are automatically better than the ones we can find in the world around us? Honed by millions of years of evolution, nature's materials have many lessons they can teach us.

How can soggy sheep keep you warm?

If you've ever gone walking on a mountain in winter, you've probably marveled at how sheep can survive in damp, cold, and utterly horrible conditions. The explanation is simple: wool is an amazingly good insulating material. The best wool of all comes from a breed of sheep called the merino; that's why sportswear companies use it in their high-performance base layers (insulating underwear for active sports like climbing, cycling, and surfing).

Photo: Sheep are built to stay warm, even when they're wet.

Several brilliant features make merino the perfect thermal underwear for sheep. First, it has much finer fibers than ordinary wool. Finer fibers means more fibers and more air trapped between them. It's trapped air that gives you warmth in clothing (that's why wearing several thin layers is generally warmer than wearing one thick pullover). You can also fluff up the surface of merino so the fibers occupy more space and trap even more air—giving more thickness and insulation with no added weight. All dry wool (and merino wool in particular) has an amazing ability to mop up steamy moisture from inside it and merino can absorb over a third of its own dry weight in water. As perspiration soaks into the fiber, it turns from a gas to a liquid, giving off what's called latent heat of fusion. The water molecules actually lock onto the wool fibers making chemical (hydrogen) bonds with them. Bonded molecules are more stable than unbonded ones, so the chemical bonding process releases energy, giving off what's called heat of sorption that keeps you warm. That's significantly different from what happens with synthetic fibers. If you wear polyester clothes and you sweat, the sweat will evaporate from your skin and cool your body down, which probably isn't too helpful if you're climbing a mountain in midwinter. But if you're wearing a merino base layer and you start to sweat, the merino will lock away the moisture and give off heat as it gets wetter, helping to keep you warm.

Will clothes ever clean themselves?

Photo: The leaves of the lotus plant (Nelumbo nucifera) are self-cleaning. Photo taken in the Wichita Mountains National Wildlife Refuge by Elise Smith, courtesy of US Fish & Wildlife Service.

One of the most irritating things about clothes is that you have to keep washing them to keep them clean. Animals wash, clean, and preen themselves too—but you don't often see plants doing the same thing. That's because some plants, like the lotus, have a clever built-in mechanism that naturally keeps them clean. The leaves are coated with nanoscopically tiny bumps and the bumps are, themselves, covered with a thin layer of wax. Dirt particles balance precariously on the waxy bumps but never get a really good grip on the main surface of the leaves below. When it rains, water droplets roll down the leaves, pulling the dirt particles free and washing them clean. The nano-bumps work a bit like a natural detergent, holding dirt clear of the leaves so water can easily wash it away. Surprise, surprise, clothing manufacturers are now coating garments like skate pants with nanofibers so they work in a similar way. The idea is that dirt is held slightly apart from the main fabric so stains cannot penetrate deeply; clothes coated with nanofibers can be washed clean much more easily.

Why does it help to swim like a shark?

Skin is an amazing material: it's waterproof, it's breathable, it helps to regulate our body temperature, and it can repair itself automatically. One thing it was never designed for was swimming. Water doesn't flow well past human skin—not least because our skin starts to wrinkle (by absorbing water) after we've been swimming or bathing for some time. If you have a particularly hairy body, every single one of your hairs will drag and slow you down even more.

Photo: Unlike humans, sharks are designed to slip easily through water. Photo of navy divers and sharks at the Newport Aquarium, Kentucky, by Davis Anderson, courtesy of US Navy.

Now you might think super-smooth suits would work better than rough ones as you swim through the pool, but the Speedo company's Fiona Fairhurst noticed something surprising: sharks have quite rough skin and still manage to swim fast. That was one of the key insights that powered the development of a revolutionary new Speedo swimsuit. Known as FASTSKIN®, the tight-fitting suit is covered with tiny v-shaped channels, just like the ridges (technically known as placoid scales or dermal denticles) on a shark's body. The idea is that water whizzes along these channels, reducing the frictional drag (essentially, turbulence) between the water and your skin, so you can swim faster.

Another of Fairhurst's important insights was to realize that a swimsuit could be engineered to force a swimmer's body into a more effective posture. So Speedo's suits fit very tightly, squeezing your body into a shape that reduces form drag (the basic resistance that the shape of an object offers as it pushes through water or air). Compressing muscles helps to reduce fatigue, so the suits also help you swim faster for longer. According to Speedo, swimsuits like this can boost a swimmer's speed by up to 3 percent. It's hardly surprising that many champion swimmers now wear suits like these. At the 2004 Sydney Olympics, swimmers kitted out in FASTSKIN earned an impressive 47 medals.

Why should clothes work like pine cones?

Photo: Pine cones naturally close in wet weather and open up in dry conditions. Something as simple as this could inspire new clothing designs.

You probably know an easy way to tell the weather. Get a pine cone and watch whether the spines open and close. If it's going to rain, the spines close up to protect the seeds inside; if it's going to stay dry, the spines open up to improve the chances of the seeds escaping. Researchers at England's Bath University and the London College of Fashion are trying to design biomimetic clothes that could work the same way. The fabric could be made with an outer layer of tiny spikes, only 1/200th of a millimeter wide. When it's hot, the spikes would open up to let out the heat, cooling you down. When it's cold, the spikes would flatten back down to trap air and provide more effective insulation.

Smart clothes

Biomimetic clothing is ingenious and inspired, but nature doesn't have all the answers. Thankfully, we also have human ingenuity to draw on in the quest for ever more useful clothes.

Clothes for health

What if your sports bra could spot breast cancer or your blouse could sense the strange palpitations of a looming heart attack? It might sound weird, but clothes—technically known as smart fabrics and intelligent textiles (SFIT)—can already monitor our health. Some years ago, a company called Textronics figured out how to build comfortable sports bras and shirts with electrode sensors naturally knitted inside the fabric to monitor an athlete's heart beat. They automatically capture puffs and palpitations and beam the data wirelessly to a monitor you wear on your wrist or stuff in your pocket. Nike+ shoes harness similar technology for health and fitness. A piezoelectric sensor (one that turns squeezing pressure into bursts of electricity), buried in your inner sole, generates a tiny electric pulse each time your foot hits the ground, firing a signal with a wireless transmitter to an iPod or iPhone in your pocket and an eager app that tracks your lap-time and personal best.

Photo: Wearable electronics could automatically monitor your health.

Sounds trivial? How about natural-looking, comfortable clothes that elderly people could wear to monitor their movements and anticipate declining health? Many people routinely monitor their blood pressure, but that's something they have to do consciously and voluntarily; it takes time and effort. Smart clothes with built in monitors not only measure standard health indicators like this, but also offer an easy and affordable way to keep tabs on things like changes in gait, caused by progressive conditions like Parkinson's disease or strokes, and to monitor, proactively, whether elderly people are more likely to fall and injure themselves.

Clothes for safety, entertainment, and power

Where health ventures, safety often follows. Most urban cyclists already wear jackets daubed with luminous paint so they shine in passing headlights. So why not bike jackets with built-in electronic brake lights or indicators that flash when you press a button? If you can stitch electrodes into clothes for things like that, why not more frivolous and entertaining things too? Why not skirts with built-in fibre-optic cables that flash and flicker on the dance floor, synced to the beat, programmed by a circuit hidden in the hem? Today's degree show project at the Royal College of Arts could be tomorrow's de-rigueur dancewear.

Flashing and flickering is pretty tame stuff. Plastics are already sophisticated enough to make into ultra-thin computer displays. Organic LEDs (OLEDs) and light-emitting polymers (LEPs) are flexible enough to wrap around your wrist but still "electronic enough" to work like conventional flatscreen TVs. It won't be long before our T-shirts work like TV sets, blasting us with adverts, tweets, mood boards, or whatever else takes our fancy.

And in a world that watches energy use like a hawk, what about turning shirts into solar panels? If you can build conductive fibres into a t-shirt and make it flash with a battery, it should be easy enough to run the same idea in reverse. With flexible solar cells mounted in the front and back panels, feeding into rechargeable batteries in your belt, you could turn yourself into a mini solar panel, trickling milliamps to your cellphone so its batteries never run down.

Suddenly, the phrase "smart clothes" takes on a whole new meaning!

#research

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rivalmoons · 7 years

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You're super interesting! Here watch: know any cool shark facts?

I definitely am not interesting, but I get to talk about sharks so its okay. (I guess I’ll just give my random favorite…. this might get long)

ooookay to start um…

-Most sharks, like great whites and makos, will drown if they stop moving because the don’t have the muscles necessary to move water through their mouths and over their gills. We didn't really know if sharks slept because they have to keep moving at all times, but last year when I watched shark week, on one of the shows scientists seemed to catch a shark “sleeping” using a robotic submarine with cameras all over it. If I remember correctly the shark (a great white) went into this sort of catatonic state at some point in the night and slowly swam against the current with her mouth open, allowing for water to flow over her gills, and for her to save energy. (Unrelated to the sleeping thing, this is why shark nets are so dangerous for them. They get caught and suffocate when they’re unable to move/breathe)

(I think this is the video from discovery)

-The great white is on average 15 feet in length, the dunkleosteus (not a shark, but a placoderm fish from the Late Devonian period (I just think they’re cool)) on average was 35 feet long, and the megalodon 80 feet long.

-The dwarf lanternshark is considered the smallest shark at about 7 inches in length. The second smallest is the pygmy shark, at 8 to 10 inches

-Sharks are cartilaginous. Teeth are the most common shark fossils one can find because most of the cartilage skeleton dissolves in salt water, but, while it is uncommon to find full body fossils, there are fossils of vertebrae, rostral nodes (kind of like its nose), and dermal denticles, which are the tiny scales that make up a shark’s skin. Basically parts of the shark with the densest cartilage.

(Because I’m lame, here’s the first link that pops up when you google “shark fossils”)

-I think it’s like 50 different species of sharks use bioluminescence. These sharks come from the Etmopteridae and Dalatiidae families.

(Article about “glow in the dark” sharks)

(A synthesis talking about the two bioluminescent sharks (It’s a bit hard to read but still cool!!))

-Sharks are like 400 million years old and have survived (all?????) five major extinctions.

-To answer something that I’m often asked: sharks Do have tongues. Its a piece of cartilage at the floor of its mouth that lacks taste buds and is called the basihyal. It doesn’t really do anything, but the cookiecutter shark uses it along with its teeth to help rip chunks of flesh out of it’s prey.

-The elegestolepis shark is considered the first shark and lived during the Silurian and Devonian periods. We really don’t know what it looked like and can only identify it from its scales.

-The Carboniferous period is sometimes called the Golden Age of Sharks. By the end of this period there were 45 families of sharks.

-The ginsu shark (cretoxyrhina mantelli), a prehistoric shark, would have been about the size of a bus.

-The puffadder shyshark is a catshark (the fact that we have “cat sharks” and “dogfish sharks” just really gets to me. idk i just love it so much)

-Bat ray fossils dating back to a million years have been found.

-Some rays, like bat and manta rays “flap,” and others move their body by undulating like a wave.

(Blue spotted stingray; waving motion)

(Bat ray; flapping motion)

-Stingrays are born fully formed and able to be self-sufficient, but will stay with their mothers until about age 3 (this is different from sharks, who don’t care for their pups after their birth)

Other facts:

I really like sharks

I tag all shark posts as #sharkive

There is also a tab on my blog leading to that tag

You can send me posts about sharks or rays at any time

And I will love you for it

And probably definitely cry

This is another ask I was sent asking about sharks

Yeah so. I know it was supposed to be about sharks but I love rays so I incorporated the shark cousins at the end. Have fun with the shark facts here’s my favorite gifs

#sharkive #sharks #shark info #shark facts #ask #anon #answered #Anonymous

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