ratio of word probabilities predicted from brain for eye and igloo

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eye

igloo

top 10 words in brain distribution (in article):
cell light human form animal muscle body produce brain water
top 10 words in brain distribution (in article):
light lamp build house type home heat allow common contain
top 10 words in brain distribution (not in article):
drink plant lamp tissue bone process wine structure beer love
top 10 words in brain distribution (not in article):
drink city wine water beer produce bottle fuel state store
times more probable under eye 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under igloo
(words not in the model)
Eyes'" are organs that detect light, and send signals along the optic nerve to the visual and other areas of the brain. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in cnidaria, mollusks, chordates, annelids and arthropods. The simplest "eyes", in even unicellular organisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment. Overview. Complex eyes can distinguish shapes and colors. The visual fields of many organisms, especially predators, involve large areas of binocular vision to improve depth perception; in other organisms, eyes are located so as to maximise the field of view, such as in rabbits and horses. The first proto-eyes evolved among animals 540 million years ago, about the time of the so-called Cambrian explosion. The last common ancestor of animals possessed the biochemical toolkit necessary for vision, and more advanced eyes have evolved in 96% of animal species in 6 of the thirty-something main phyla. In most vertebrates and some mollusks, the eye works by allowing light to enter it and project onto a light-sensitive panel of cells, known as the retina, at the rear of the eye. The cone cells (for color) and the rod cells (for low-light contrasts) in the retina detect and convert light into neural signals for vision. The visual signals are then transmitted to the brain via the optic nerve. Such eyes are typically roughly spherical, filled with a transparent gel-like substance called the vitreous humour, with a focusing lens and often an iris; the relaxing or tightening of the muscles around the iris change the size of the pupil, thereby regulating the amount of light that enters the eye, and reducing aberrations when there is enough light. The eyes of cephalopods, fish, amphibians and snakes usually have fixed lens shapes, and focusing vision is achieved by telescoping the lens similar to how a camera focuses. Compound eyes are found among the arthropods and are composed of many simple facets which, depending on the details of anatomy, may give either a single pixelated image or multiple images, per eye. Each sensor has its own lens and photosensitive cell(s). Some eyes have up to 28,000 such sensors, which are arranged hexagonally, and which can give a full 360-degree field of vision. Compound eyes are very sensitive to motion. Some arthropods, including many Strepsiptera, have compound eyes of only a few facets, each with a retina capable of creating an image, creating vision. With each eye viewing a different thing, a fused image from all the eyes is produced in the brain, providing very different, high-resolution images. Possessing detailed hyperspectral color vision, the Mantis shrimp has been reported to have the world's most complex color vision system. Trilobites, which are now extinct, had unique compound eyes. They used clear calcite crystals to form the lenses of their eyes. In this, they differ from most other arthropods, which have soft eyes. The number of lenses in such an eye varied, however: some trilobites had only one, and some had thousands of lenses in one eye. In contrast to compound eyes, simple eyes are those that have a single lens. For example, jumping spiders have a large pair of simple eyes with a narrow field of view, supported by an array of other, smaller eyes for peripheral vision. Some insect larvae, like caterpillars, have a different type of simple eye (stemmata) which gives a rough image. Some of the simplest eyes, called ocelli, can be found in animals like some of the snails, which cannot actually "see" in the normal sense. They do have photosensitive cells, but no lens and no other means of projecting an image onto these cells. They can distinguish between light and dark, but no more. This enables snails to keep out of direct sunlight. In organisms dwelling near deep-sea vents, compound eyes have been secondarily simplified and adapted to spot the infra-red light produced by the hot vents in this way the bearers can spot hot springs and avoid being boiled alive. Evolution. Visual pigments appear to An igloo'" (Inuit language: "iglu", Inuktitut syllabics: ᐃᒡᓗ, "house", plural: "iglooit" or "igluit", but in English commonly "igloos"), translated sometimes as snowhouse'", is the Inuit word for house or habitation, and is not restricted exclusively to snowhouses but includes traditional tents, sod houses, homes constructed of driftwood and modern buildings. Igloo as a snowhouse. When referring to a snowhouse, igloos are shelters constructed from blocks of snow, generally in the form of a dome. Although igloos are usually associated with all Inuit, they were predominantly constructed by people of Canada's Central Arctic and Greenland's Thule area. Other Inuit people tended to use snow to insulate their houses which consisted of whalebone and hides. Snow was used because the air pockets trapped in it make it an insulator. On the outside, temperatures may be as low as, but on the inside the temperature may range from to when warmed by body heat alone. Traditional types. There were three traditional types of igloos, all of different sizes and all used for different purposes. The smallest was constructed as a temporary shelter, usually only used for one or two nights. These were built and used during hunting trips, often on open sea ice. Next in size was the semi-permanent, intermediate-sized family dwelling. This was usually a single room dwelling that housed one or two families. Often there were several of these in a small area, which formed an "Inuit village". The largest of the igloos was normally built in groups of two. One of the buildings was a temporary structure built for special occasions, the other built nearby for living. These might have had up to five rooms and housed up to 20 people. A large igloo might have been constructed from several smaller igloos attached by their tunnels, giving common access to the outside. These were used to hold community feasts and traditional dances. Modifications. The Central Inuit, especially those around the Davis Strait, lined the living area with skin, which could increase the temperature within from around 2 °C (36 °F) to 10-20 °C (50-68 °F). Construction. The snow used to build an igloo must have sufficient structural strength to be cut and stacked in the appropriate manner. The best snow to use for this purpose is snow which has been blown by wind, which can serve to compact and interlock the ice crystals. The hole left in the snow where the blocks are cut from is usually used as the lower half of the shelter. Sometimes, a short tunnel is constructed at the entrance to reduce wind and heat loss when the door is opened. Due to snow's excellent insulating properties, inhabited igloos are surprisingly comfortable and warm inside. In some cases a single block of ice is inserted to allow light into the igloo. Architecturally, the igloo is unique in that it is a dome that can be raised out of independent blocks leaning on each other and polished to fit without an additional supporting structure during construction. The igloo, if correctly built, will support the weight of a person standing on the roof. Also, in the traditional Inuit igloo the heat from the kulliq (stone lamp) causes the interior to melt slightly. This melting and refreezing builds up an ice sheet and contributes to the strength of the igloo. The sleeping platform is a raised area compared to where one enters the igloo. Because warmer air rises and cooler air settles, the entrance area will act as a cold trap whereas the sleeping area will hold whatever heat is generated by a stove, lamp or body heat. In popular use. In heraldry, the igloo appears as the crest in the coat of arms of Nunavut. "Nanook of the North". The 1922 documentary "Nanook of the North" contains the oldest surviving movie footage of an Inuit constructing an igloo. In the film, Nanook (real name Allakariallak) builds a large family igloo as well as a smaller igloo for sled pups. Nanook demonstrates the use of an ivory knife to cut and trim snow block, as well as the use of clear ice for a window. His igloo was built in about one hour, and was large enough for five people. The igloo was cross-sectioned for filmmaking, so interior shots could be made. See "External links" for video footage.