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robertogreco : anatomy   37

Revealed: why animals' pupils come in different shapes and sizes
"Wolves and foxes are closely related and share many of the same characteristics. But look at their eyes – where wolves have rounded pupils like humans, foxes instead have a thin vertical line. But it isn’t just canines –across the animal kingdom, pupils come in all shapes and sizes. So why the differences?

It’s a question that has long interested scientists working on vision and optics. In a new study published in the journal Science Advances, colleagues from Durham, Berkeley and I explain why these pupil shapes have developed.

Goats, sheep, horses, domestic cats, and numerous other animals have pupils which vary from fully circular in faint light to narrow slits or rectangles in bright light. The established theory for this is that elongated pupils allow greater control of the amount of light entering the eye. For instance, a domestic cat can change its pupil area by a factor of 135 from fully dilated to fully constricted, whereas humans, with a round pupil, can only change area by a factor of 15. This is particularly useful for animals that are active both day and night, allowing for much better vision in low light conditions.

However, if the only reason for elongated pupils was to control the amount of light entering the eye, the orientation would not be important: horizontal, vertical, or diagonal would all offer the same advantages. Instead, the pupils are almost always horizontal or vertical, which suggests there must be other benefits which explain this orientation.

Pupils fit for every niche

Our work has focused on the visual benefits of vertical and horizontal pupils in mammals and snakes. One of the most interesting factors we found is that the orientation of the pupil can be linked to an animal’s ecological niche. This has been described before, but we went one step further to quantify the relationship.

We found animals with vertically elongated pupils are very likely to be ambush predators which hide until they strike their prey from relatively close distance. They also tend to have eyes on the front of their heads. Foxes and domestic cats are clear examples of this. The difference between foxes and wolves is down to the fact wolves are not ambush predators – instead they hunt in packs, chasing down their prey.

In contrast, horizontally elongated pupils are nearly always found in grazing animals, which have eyes on the sides of their head. They are also very likely to be prey animals such as sheep and goats.

We produced a computer model of eyes which simulates how images appear with different pupil shapes, in order to explain how orientation could benefit different animals. This modelling showed that the vertically elongated pupils in ambush predators enhances their ability to judge distance accurately without having to move their head, which could give away their presence to potential prey.

Grazing animals have different problems to deal with. They need to check all around for prey and they need to flee rapidly in case of attack. Having eyes towards the side of their head helps them to see nearly all around them. Having a horizontal pupil enhances the amount of light they can receive in front of and behind them while reducing the amount of light from above and below. This allows them panoramic vision along the ground to help detect potential predators as early as possible. The horizontal pupil also enhances the image quality of horizontal planes and this enhanced view at ground level is also an advantage when running at speed to escape.

So, vertically elongated pupils help ambush predators capture their prey and horizontally elongated pupils help prey animals avoid their predators.

We realised our hypothesis predicted that shorter animals should have a greater benefit from vertical pupils than taller ones. So we rechecked the data on animals with frontal eyes and vertical pupils and found that 82% are what is considered “short” (which we defined as having a shoulder height of less than 42cm) compared with only 17% of animals with circular pupils.

We also realised that there is a potential problem with the theory for horizontal elongation. If horizontal pupils are such an advantage to grazing animals, what happens when they bend their head down to graze? Is the pupil no longer horizontally aligned with the ground?

We checked this by observing animals in both a zoo and on farms. We found that eyes of goats, deer, horses, and sheep rotate as they bend their head down to eat, keeping the pupil aligned with the ground. This remarkable eye movement, which is in opposite directions in the two eyes, is known as cyclovergence. Each eye in these animals rotates by 50 degrees, possibly more (we can only make the same movement by a few degrees).

There are still some unexplained pupils in nature. For example, mongooses have forward-facing eyes but horizontal pupils, geckos have huge circular pupils when dilated which reduce down to several discrete pinholes when constricted and cuttlefish have “W”-shaped pupils. Understanding all these variations is an interesting challenge for the future."
eyes  animals  vision  pupils  biology  anatomy  2016  via:anne  science  optics  eyesight 
march 2016 by robertogreco
The American Scholar: Joyas Volardores - Brian Doyle
"Consider the hummingbird for a long moment. A hummingbird’s heart beats ten times a second. A hummingbird’s heart is the size of a pencil eraser. A hummingbird’s heart is a lot of the hummingbird. Joyas volardores, flying jewels, the first white explorers in the Americas called them, and the white men had never seen such creatures, for hummingbirds came into the world only in the Americas, nowhere else in the universe, more than three hundred species of them whirring and zooming and nectaring in hummer time zones nine times removed from ours, their hearts hammering faster than we could clearly hear if we pressed our elephantine ears to their infinitesimal chests.

Each one visits a thousand flowers a day. They can dive at sixty miles an hour. They can fly backwards. They can fly more than five hundred miles without pausing to rest. But when they rest they come close to death: on frigid nights, or when they are starving, they retreat into torpor, their metabolic rate slowing to a fifteenth of their normal sleep rate, their hearts sludging nearly to a halt, barely beating, and if they are not soon warmed, if they do not soon find that which is sweet, their hearts grow cold, and they cease to be. Consider for a moment those hummingbirds who did not open their eyes again today, this very day, in the Americas: bearded helmet-crests and booted racket-tails, violet-tailed sylphs and violet-capped woodnymphs, crimson topazes and purple-crowned fairies, red-tailed comets and amethyst woodstars, rainbow-bearded thornbills and glittering-bellied emeralds, velvet-purple coronets and golden-bellied star-frontlets, fiery-tailed awlbills and Andean hillstars, spatuletails and pufflegs, each the most amazing thing you have never seen, each thunderous wild heart the size of an infant’s fingernail, each mad heart silent, a brilliant music stilled.

Hummingbirds, like all flying birds but more so, have incredible enormous immense ferocious metabolisms. To drive those metabolisms they have race-car hearts that eat oxygen at an eye-popping rate. Their hearts are built of thinner, leaner fibers than ours. Their arteries are stiffer and more taut. They have more mitochondria in their heart muscles—anything to gulp more oxygen. Their hearts are stripped to the skin for the war against gravity and inertia, the mad search for food, the insane idea of flight. The price of their ambition is a life closer to death; they suffer more heart attacks and aneurysms and ruptures than any other living creature. It’s expensive to fly. You burn out. You fry the machine. You melt the engine. Every creature on earth has approximately two billion heartbeats to spend in a lifetime. You can spend them slowly, like a tortoise and live to be two hundred years old, or you can spend them fast, like a hummingbird, and live to be two years old.

The biggest heart in the world is inside the blue whale. It weighs more than seven tons. It’s as big as a room. It is a room, with four chambers. A child could walk around it, head high, bending only to step through the valves. The valves are as big as the swinging doors in a saloon. This house of a heart drives a creature a hundred feet long. When this creature is born it is twenty feet long and weighs four tons. It is waaaaay bigger than your car. It drinks a hundred gallons of milk from its mama every day and gains two hundred pounds a day, and when it is seven or eight years old it endures an unimaginable puberty and then it essentially disappears from human ken, for next to nothing is known of the the mating habits, travel patterns, diet, social life, language, social structure, diseases, spirituality, wars, stories, despairs and arts of the blue whale. There are perhaps ten thousand blue whales in the world, living in every ocean on earth, and of the largest animal who ever lived we know nearly nothing. But we know this: the animals with the largest hearts in the world generally travel in pairs, and their penetrating moaning cries, their piercing yearning tongue, can be heard underwater for miles and miles.

Mammals and birds have hearts with four chambers. Reptiles and turtles have hearts with three chambers. Fish have hearts with two chambers. Insects and mollusks have hearts with one chamber. Worms have hearts with one chamber, although they may have as many as eleven single-chambered hearts. Unicellular bacteria have no hearts at all; but even they have fluid eternally in motion, washing from one side of the cell to the other, swirling and whirling. No living being is without interior liquid motion. We all churn inside.

So much held in a heart in a lifetime. So much held in a heart in a day, an hour, a moment. We are utterly open with no one in the end—not mother and father, not wife or husband, not lover, not child, not friend. We open windows to each but we live alone in the house of the heart. Perhaps we must. Perhaps we could not bear to be so naked, for fear of a constantly harrowed heart. When young we think there will come one person who will savor and sustain us always; when we are older we know this is the dream of a child, that all hearts finally are bruised and scarred, scored and torn, repaired by time and will, patched by force of character, yet fragile and rickety forevermore, no matter how ferocious the defense and how many bricks you bring to the wall. You can brick up your heart as stout and tight and hard and cold and impregnable as you possibly can and down it comes in an instant, felled by a woman’s second glance, a child’s apple breath, the shatter of glass in the road, the words I have something to tell you, a cat with a broken spine dragging itself into the forest to die, the brush of your mother’s papery ancient hand in the thicket of your hair, the memory of your father’s voice early in the morning echoing from the kitchen where he is making pancakes for his children."
2012  briandoyle  via:jenlowe  animals  nature  birds  hummingbirds  numbers  time  repetition  metabolism  biology  hearts  whales  bluewhales  mammals  anatomy  lifetimes  scale  size  life  speed  velocity 
january 2015 by robertogreco
paper torso - a set on Flickr
"A torso with removable organs for the Science Lab of the International School Nadi, Fiji Islands built entirely from 200gms/sqm white card. Templates for some of the organs are available now:"
humananatomy  human  papercraft  sculpture  design  art  anatomy 
march 2012 by robertogreco
12:31
"In 1993, a convicted murderer was executed. His body was given to science, segmented, and photographed for medical research. In 2011, we used photography to put it back together."<br />
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"This animation represents the entire data set (1,871 slices) of the male cadaver from the Visible Human Project. The animation was played fullscreen on a computer, which was moved around by an assistant while being photographed in a dark environment. The resulting images are long-exposure "light paintings" of the entire cadaver. Variations in the movement of the computer during each exposure created differences in the shape of the body throughout the series."
photography  art  light  visiblehumanproject  anatomy  body  croixgagnon  frankschott  paintingwithlight  bodies 
april 2011 by robertogreco
Move: Choreographing You / Amanda Levete | ArchDaily
"The exhibition design was driven by the relationships between choreography and geometry, movement and form. Inspired by the photographic motion studies of the human body of Etienne-Jules Marey and Eadweard Muybridge, we have created a collection of spatial dividers which are defined by a serial transformation of a single material: a sequence of folded oscillations of Dupont Tyvek. The resulting translucent paper-like fabric ribbons, a counterpoint to the brutality of the building, rise and fall with undulating folds which simultaneously define themselves as way finding devices, partitions, suspended ceilings, and portals. These fluid spatial and formal transformations choreograph the movement of the visitor through areas of sculpture, film, archive and performance."
choreography  architecture  sculpture  eadweardmuybridge  etienne-julesmarey  anatomy  human  body  movement  geometry  form  motion  motionstudies  fabric  glvo  bodies 
december 2010 by robertogreco
Anatomical illustrations from Edo-period Japan ::: Pink Tentacle
"Here is a selection of old anatomical illustrations that provide a unique perspective on the evolution of medical knowledge in Japan during the Edo period (1603-1868)."
anatomy  biology  history  illustration  japan  medicine  art  edo  human  glvo 
october 2010 by robertogreco
Human Connections Start With A Friendly Touch : NPR
"Social scientists have shown in many studies over the years that supportive touch can have good outcomes in a number of different realms. Consider the following examples: If a teacher touches a student on the back or arm, that student is more likely to participate in class. The more athletes high-five or hug their teammates, the better their game. A touch can make patients like their doctors more. If you touch a bus driver, he's more likely to let you on for free. If a waitress touches the arm or shoulder of a customer, she may get a larger tip.<br />
<br />
But why does a friendly or supportive touch have such universal and positive effects? What's happening in our brains and bodies that accounts for this magic?"
touch  neuroscience  medicine  behavior  teaching  anatomy  psychology  nonverbal  research 
september 2010 by robertogreco
Turning The Pages Online: Book Menu
"Using touchscreen technology and animation software, the digitized images of rare and beautiful historic books in the biomedical sciences are offered at kiosks at the U.S. National Library of Medicine. Visitors may ‘touch and turn’ these pages in a highly realistic way. They can zoom in on the pages for more detail, read or listen to explanations of the text, and (in some cases) access additional information on the books in the form of curators’ notes.
via:preoccupations  medicine  renaissance  science  education  art  biology  illustration  images  anatomy  reference  libraries  medical  zoology  archives  history  digitallibraries  nlm  books 
december 2009 by robertogreco
collision detection: 41% of museums don't know how dogs actually walk
"But the fact is quadruped leg-motion isn’t intuitive: When you close your eyes and visualize it, it makes more sense for the legs to alternate steps left and right, much like the screwed-up skeleton above. What we see in our mind’s eye doesn’t match what we actually see in the world around us — so we ignore the evidence in front of our eyes. It’s kind of like how Aristotle maintained that men had more teeth than women because it made more sense to him, and never bothered to actually check inside an actual woman’s mouth."
animals  motion  dogs  glvo  eadweardmuybridge  anatomy  museums  clivethompson  movement  animation  taxidermy  science 
february 2009 by robertogreco
Think Anatomy
"We’ve found links to the best anatomy resources on the Internet, categorized them, reviewed them, and put them in one place for you—ThinkAnatomy. Not everyone can get their study needs met through lecture, lab, and a textbook. You probably find yourself searching for other study aids. But, we also know how frustrating it can be to search the Internet for good resources, and let’s be honest, there’s a lot of bad information out there."
human  anatomy  biology  science  visualization  illustration  3d  database  teaching  learning  studyguides  tcsnmy  medical  medicine  elearning  reference  education 
november 2008 by robertogreco
Athletes’ Body Types Are Often Similar, but Atypical Can Thrive - NYTimes.com
"Usain Bolt is too tall to be a world-class sprinter. Mike Friedman is too heavy to be an elite cyclist. Stefan Holm is too short to be champion high jumper, and Erin Donohue is too short and stocky be a star middle-distance runner. Yet all of them are Olympians, and athletic anomalies, bucking conventional wisdom and somehow rising to the same arenas as Michael Phelps, He Kexin and Dara Torres."
athletics  athletes  humans  anatomy  bodies  sports  competition  olympics  anomolies  body 
august 2008 by robertogreco
borborygmus: Definition and Much More from Answers.com
"A rumbling noise produced by the movement of gas through the intestines."
digestion  glvo  anatomy  words  definitions 
may 2008 by robertogreco
You Walk Wrong
"It took 4 million years of evolution to perfect the human foot. But we’re wrecking it with every step we take."
shoes  health  walking  barefoot  feet  culture  anatomy 
april 2008 by robertogreco
Design and the Elastic Mind
"The exhibition highlights designers’ ability to grasp momentous changes in technology, science, and history—changes that demand or reflect major adjustments in human behavior—and translate them into objects that people can actually understand and u
design  future  interface  stamendesign  moma  exhibits  interactive  webdesign  gallery  infographics  information  visualization  art  architecture  patterns  biology  scale  technology  inspiration  form  paolaantonelli  nanotechnology  nature  science  human  anatomy  eames  designandtheelasticmind  webdev 
february 2008 by robertogreco
Chickensaurus Skeleton | Geekdad from Wired.com
"As a lesson in anatomy, my son and I reassembled a chicken skeleton from the bones remaining after a chicken dinner. We cleaned and dried the bones, then hot-glued them together."
fun  kids  learning  projects  edg  glvo  anatomy  animals  chickens  science  kevinkelly  education  homeschool  unschooling  howto  parenting  diy 
february 2008 by robertogreco
Design and the Elastic Mind - Design - Review - New York Times
"Although fascination with organic form...since Renaissance...now entered age in which designers & architects...drawing inspiration from hidden patterns in nature rather...results can be scary, but they may also hold the key to paradise."
art  design  architecture  patterns  biology  scale  technology  moma  designandtheelasticmind  exhibits  inspiration  form  paolaantonelli  nanotechnology  nature  science  human  anatomy  eames 
february 2008 by robertogreco
Bodies of Knowledge
"This site looks at the way different cultures, at various points in history, have looked at the body, and how these ideas have been translated into pictures. Click on the links below to explore all sorts of bodily curiosities."
anatomy  biology  human  history  culture  philosophy  physiology  illustration  medicine  pseudoscience  visualization  exhibits  body  cryptozoology  drawing  bodies 
february 2008 by robertogreco
Visual dictionary
"to learn by way of image with thematic, clear and precise pages, with concise and rigorous texts, bilingual, the InfoVisual will become a academic resource. Different from an encyclopedia or from a traditional online dictionaries, thesauri and glossaries
dictionary  language  visualization  visual  diagrams  graphics  medical  encyclopedias  anatomy  biology  dictionaries 
january 2008 by robertogreco
dissected cartography - data visualization & visual design - information aesthetics
"'world map' is a series of deconstructed and reconstructed maps, based on historical factors, and correspondences or quirks of the map itself. 'geographic pathologies' is an experiment with connections between geography and anatomy."
cartography  design  maps  mapping  geography  history  anatomy 
january 2008 by robertogreco
Google Body | Beyond the Beyond from Wired.com
"I'd pay plenty for a service that could search the interior of my body and compare its state to that of yesterday and a year ago. Just to know what that *twinge* really means, or what's going on with that aching tooth... Who wouldn't pay for that?"
anatomy  google  science  technology  scifi 
november 2007 by robertogreco
Skeleton crew: The photographs of Patrick Gries | Arts | Guardian Unlimited
"Strip any creature of its flesh, and the process of evolution is laid bare. These photographs by Patrick Gries from his book with Jean-Baptiste de Panafieu, Evolution in Action, celebrate the stories told and the beauty revealed by skeletons."
evolution  photography  animals  skeletons  anatomy 
november 2007 by robertogreco
Pneumatic Anatomica by ~freeny on deviantART
"After months of observations, dissections and a 25 minute intro to clown school, I have finally successfully mapped the inter workings of the domestic balloon dog."
illustration  drawing  balloons  animals  anatomy 
october 2007 by robertogreco
Historical Anatomies on the Web: Browse Titles
"Images have been selected from the following anatomical atlases in the National Library of Medicine's collection. Each atlas is linked to a brief Author & Title Description, which offers an historical discussion of the work, its author, the artists, and
human  anatomy  science  glvo  images  visual  books  drawings  diagrams  libraries  graphics  history  medicine  archives  biology  body  collections  bodies 
october 2007 by robertogreco
Dream Anatomy: A National Library of Medicine Exhibit
"Dream Anatomy (October 9, 2002 to July 31, 2003) was mainly drawn from the National Library of Medicine's extensive historical collections. The Library's resources for historical scholarship in medicine and related sciences are among the richest of any i
anatomy  anthropology  art  body  glvo  history  human  illustration  diagrams  drawings  collections  evolution  graphics  design  museums  science  bodies 
september 2007 by robertogreco
Dream Anatomy: Gallery [children's drawings]
In conjunction with the Dream Anatomy exhibit, the National Library of Medicine decided to hold an art contest and ask children between the ages of five and thirteen what they thought the body looked like “under the skin.”
anatomy  children  graphics  illustration  art  glvo  medicine  science  body  bodies 
september 2007 by robertogreco
Dream Anatomy: Gallery: Fritz Kahn: Man as Industrial Palace
"Kahn’s modernist visualization of the digestive and respiratory system as "industrial palace," really a chemical plant, was conceived in a period when the German chemical industry was the world’s most advanced."
anatomy  visualization  illustration  infodesign  industry  medicine  design  history  art  body  human  modernism  bodies 
september 2007 by robertogreco
Boing Boing: Miniature anatomical toys from Japan
"Bob Knetzger, an amazing toy designer and MAKE magazine contributer, recently went to Japan and discovered tiny anatomical toys there."
japan  science  anatomy  biology  human  toys  medicine 
july 2007 by robertogreco
BUILT REPORT - Schwarzenegger Cows Photo Gallery
"Belgian Blue Beef are famous for their "double muscling" due to a gene that suppresses the production of Myostatin. Myostatin is a protein that normally inhibits muscle growth after a certain point of development. Pure Belgian Blue carry two copies of th
anatomy  animals  medicine  biology  cows  genetics  oddities 
july 2007 by robertogreco
Pirouette or Plod? -- Cevallos 2007 (622): 2 -- ScienceNOW
"You can tell how nimble an animal is without even looking at its legs: Simply check the size of its inner ear. A new study shows that agile animals, such as tree-swinging gibbons or brown bats, have relatively larger ear canals than their lumbering count
animals  biology  anatomy  science  nature  motion 
june 2007 by robertogreco

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