ratio of word probabilities predicted from brain for beetle and car

beetle	car
top 10 words in brain distribution (in article): plant species seed power animal water leaf food common variety	top 10 words in brain distribution (in article): animal city human cell people species build form state store
top 10 words in brain distribution (not in article): fruit grow produce tree station flower sugar train line signal	top 10 words in brain distribution (not in article): love sexual male house female god woman street cat wolf
times more probable under beetle 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under car (words not in the model)
Beetles'" are the group of insects with the largest number of known species. They are placed in the order "'Coleoptera'" (from Greek, "koleos", "sheath"; and, "pteron", "wing", thus "sheathed wing"), which contains more described species than in any other order in the animal kingdom, constituting about 25% of all known life-forms. 40% of all described insect species are beetles (about 350,000 species), and new species are frequently discovered. Estimates put the total number of species, described and undescribed, at between 5 and 8 million. Beetles can be found in almost all habitats, but are not known to occur in the sea or in the polar regions. They interact with their ecosystems in several ways. They often feed on plants and fungi, break down animal and plant debris, and eat other invertebrates. Some species are prey of various animals including birds and mammals. Certain species are agricultural pests, such as the Colorado potato beetle "Leptinotarsa decemlineata", the boll weevil "Anthonomus grandis", the red flour beetle "Tribolium castaneum", and the mungbean or cowpea beetle "Callosobruchus maculatus", while other species of beetles are important controls of agricultural pests. For example, beetles in the family Coccinellidae ("ladybirds" or "ladybugs") consume aphids, scale insects, thrips, and other plant-sucking insects that damage crops. Description. The name "Coleoptera" was given by Aristotle for the hardened shield-like forewing (coleo= shield+ ptera= wing). Other characters of this group which are believed to be monophyletic include a holometabolous life cycle; having a prothorax that is distinct from and freely articulating with the mesothorax; the meso- and meta-thoracic segments fusing to form a pterothorax; a depressed body shape with the legs on the ventral surface; the coxae of legs recessed into cavities formed by heavily sclerotized thoracic sclerites; the abdominal sternites more sclerotized than the tergites; antennae with 11 or fewer segments; and terminal genitalic appendages retracted into the abdomen and invisible at rest. The general anatomy of beetles is quite uniform, although specific organs and appendages may vary greatly in appearance and function between the many families in the order. Like all insects, beetles' bodies are divided into three sections: the head, the thorax, and the abdomen. When viewed from below, the thorax is that part from which all three pairs of legs and both pairs of wings arise. The abdomen is everything posterior to the thorax. When viewed from above, most beetles appear to have three clear sections, but this is deceptive: on the beetle's upper surface, the middle "section" is a hard plate called the pronotum, which is only the front part of the thorax; the back part of the thorax is concealed by the beetle's wings. Like all arthropods, beetles are segmented organisms, and all three of the major sections of the body are themselves composed of several further segments, although these are not always readily discernible. This further segmentation is usually best seen on the abdomen. Beetles are generally characterised by a particularly hard exoskeleton and hard forewings (elytra). The beetle's exoskeleton is made up of numerous plates called sclerites, separated by thin sutures. This design creates the armoured defences of the beetle while maintaining flexibility. The elytra are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings ("alae"). The elytra must be raised in order to move the hind flight wings. A beetle's flight wings are crossed with veins and are folded after landing, often along these veins, and are stored below the elytra. In some beetles, the ability to fly has been lost. These include the ground beetles (family Carabidae) and some "true weevils" (family Curculionidae), but also some desert and cave-dwelling species of other families. Many of these species have the two elytra fused together, forming a solid shield over the abdomen. In a few families, both the ability to fly and the elytra have been lost, with the best known example being the glow-worms of the family Phengodidae, in which the females are larviform throughout their lives. Beetles have mouthparts similar to those of grasshoppers. Of these parts, the most commonly known are probably the mandibles, which appear as large pincers on the front of some beetles. The mandibles are a pair of hard, often tooth-like structures that move horizontally to grasp, crush, or cut food or enemies (see defence, below). Two pairs of finger-like appendages are found around the mouth in most beetles, serving to move food into the mouth. These are the maxillary and labial palpi. The eyes are compound and may display remarkable adaptability, as in the case of whirligig beetles (family Gyrinidae), in which the eyes are split to allow a view both above and below the waterline. Other species also have divided eyes — some longhorn beetles (family Cerambycidae) and weevils — while many beetles have eyes that are notched to some degree. A few beetle genera also possess ocelli, which are small, simple eyes usually situated farther back on the head (on the vertex). Beetles' antennae are primarily organs of smell, but may also be used to feel out a beetle's environment physically. They may also be used in some families during mating, or among a few beetles for defence. Antennae vary greatly in form within the Coleoptera, but are often similar within any given family. In some cases, males and females of the same species will have different antennal forms. Antennae may be clavate (flabellate and lamellate are sub-forms of clavate, or clubbed antennae), filiform, geniculate, moniliform, pectinate, or serrate. For images of these antennal forms see antenna (biology). The legs, which are multi-segmented, end in two to five small segments called tarsi. Like many other insect orders beetles bear claws, usually one pair, on the end of the last tarsal segment of each leg. While most beetles use their legs for walking, legs may be variously modified and adapted for other uses. Among aquatic families — Dytiscidae, Haliplidae, many species of Hydrophilidae and others — the legs, most notably the last pair, are modified for swimming and often bear rows of long hairs to aid this purpose. Other beetles have fossorial legs that are widened and often spined for digging. Species with such adaptations are found among the scarabs, ground beetles, and clown beetles (family Histeridae). The hind legs of some beetles, such as flea beetles (within Chrysomelidae) and flea weevils (within Curculionidae), are enlarged and designed for jumping. Oxygen is obtained via a tracheal system. Air enters a series of tubes along the body through openings called spiracles, and is then taken into increasingly finer fibres. Pumping movements of the body force the air through the system. Beetles have hemolymph instead of blood, and the open circulatory system of the beetle is powered by a tube-like heart attached to the top inside of the thorax. Development. Beetles are endopterygotes with complete metamorphosis. A single female may lay from several dozen to several thousand eggs during her lifetime. Eggs are usually laid according to the substrate the larva will feed on upon hatching. Among others, they can be laid loose in the substrate (e.g. flour beetle), laid in clumps on leaves (e.g. Colorado potato beetle), or individually attached (e.g. mungbean beetle and other seed borers) or buried in the medium (e.g. carrot weevil). The larva is usually the principal feeding stage of the beetle life cycle. Larvae tend to feed voraciously once they emerge from their eggs. Some feed externally on plants, such as those of certain leaf beetles, while others feed within their food sources. Examples of internal feeders are most Buprestidae and longhorn beetles. The larvae of many beetle families are predatory like the adults (ground beetles, ladybirds, rove beetles). The larval period varies between species but can be as long as several years. Beetle larvae can be differentiated from other insect larvae by their hardened, often darkened head, the presence of chewing mouthparts, and spiracles along the sides of the body. Like adult beetles, the larvae are varied in appearance, particularly between beetle families. Beetles whose larvae are somewhat flattened and are highly mobile are the ground beetles, some rove beetles, and others; their larvae are described as campodeiform. Some beetle larvae resemble hardened worms with dark head capsules and minute legs. These are elateriform larvae, and are found in the click beetle (Elateridae) and darkling beetle (Tenebrionidae) families. Some elateriform larvae of click beetles are known as wireworms. Beetles in the families of the Scarabaeoidea have short, thick larvae described as scarabaeiform, but more commonly known as grubs. All beetle larvae go through several instars, which are the developmental stages between each moult. In many species the larvae simply increase in size with each successive instar as more food is consumed. In some cases, however, more dramatic changes occur. Among certain beetle families or genera, particularly those that exhibit parasitic lifestyles, the first instar (the planidium) is highly mobile in order to search out a host, while the following instars are more sedentary and remain on or within their host. This is known as hypermetamorphosis; examples include the blister beetles (family Meloidae) and some rove beetles, particularly those of the genus "Aleochara". As with all endopterygotes, beetle larvae pupate, and from this pupa emerges a fully formed, sexually mature adult beetle, or imago. Adults have an extremely variable lifespan, from weeks to years, depending on the species. Reproduction. Beetles may display extremely intricate behaviour when mating. Pheromone communication is thought to be important in the location of a mate. Conflict can play a part in the mating rituals of species such as burying beetles (genus "Nicrophorus") where conflicts between males and females rage until only one of each is left, thus ensuring reproduction by the strongest and fittest. Many male beetles are territorial and will fiercely defend their small patch of territory from intruding males. In such species, the males may often have horns on the head and or thorax, making their overall body lengths greater than those of the females, unlike most insects. Pairing is generally short but in some cases will last for several hours. During pairing sperm cells are transferred to the female to fertilise the egg. Parental care varies between species, ranging from the simple laying of eggs under a leaf to certain scarab beetles, which construct underground structures complete with a supply of dung to house and feed their young. Other beetles are leaf rollers, biting sections of leaves to cause them to curl inwards, then laying their eggs, thus protected, inside. Defense. Beetles and their larvae have a variety of strategies to avoid being attacked by predators or parasitoids. These include camouflage, mimicry, toxicity, and active defense. Camouflage involves the use of colouration or shape to blend into the surrounding environment. This sort of protective coloration is common and widespread among beetle families, especially those that feed on wood or vegetation, such as many of the leaf beetles (family Chrysomelidae) or weevils. In some of these species, sculpturing or various coloured scales or hairs cause the beetle to resemble bird dung or other inedible objects. Many of those that live in sandy environments blend in with the coloration of the substrate. Another defence that often uses colour or shape to deceive potential enemies is mimicry. A number of longhorn beetles (family Cerambycidae) bear a striking resemblance to wasps, which helps them avoid predation even though the beetles are in fact harmless. This defence can be found to a lesser extent in other beetle families, such as the scarab beetles. Beetles may combine their colour mimicry with behavioural mimicry, acting like the wasps they already closely resemble. Many beetle species, including ladybirds, blister beetles, and lycid beetles can secrete distasteful or toxic substances to make them unpalatable or even poisonous. These same species often exhibit aposematism, where bright or contrasting colour patterns warn away potential predators, and there are, not surprisingly, a great many beetles and other insects that mimic these chemically-protected species. Large ground beetles and longhorn beetles may defend themselves using strong mandibles and or spines or horns to forcibly persuade a predator to seek out easier prey. Others, such as bombardier beetles (within Carabidae), may spray chemicals from their abdomen to repel predators. Feeding. Besides being abundant and varied, the Coleoptera are able to exploit the wide diversity of food sources available in their many habitats. Some are omnivores, eating both plants and animals. Other beetles are highly specialised in their diet. Many species of leaf beetles, longhorn beetles, and weevils are very host specific, feeding on only a single species of plant. Ground beetles and rove beetles (family Staphylinidae), among others, are primarily carnivorous and will catch and consume many other arthropods and small prey such as earthworms and snails. While most predatory beetles are generalists, a few species have more specific prey requirements or preferences. Decaying organic matter is a primary diet for many species. This can range from dung, which is consumed by coprophagous species such as certain scarab beetles (family Scarabaeidae), to dead animals, which are eaten by necrophagous species such as the carrion beetles (family Silphidae). Some of the beetles found within dung and carrion are in fact predatory, such as the clown beetles, preying on the larvae of coprophagous and necrophagous insects. Adaptations to the environment. Aquatic beetles use several techniques for retaining air beneath the water's surface. Beetles of the family Dytiscidae hold air between the abdomen and the elytra when diving. Hydrophilidae have hairs on their under surface that retain a layer of air against their bodies. Adult crawling water beetles use both their elytra and their hind coxae (the basal segment of the back legs) in air retention  while whirligig beetles simply carry an air bubble down with them whenever they dive. Evolutionary history and classification. While some authorities believe modern beetles began about 140 million years ago, research announced in 2007 showed that beetles may have entered the fossil record during the Lower Permian, about 265 to 300 million years ago. The four extant suborders of beetle are these: These suborders diverged in the Permian and Triassic. Their phylogenetic relationship is uncertain, with the most popular hypothesis being that Polyphaga and Myxophaga are most closely related, with Adephaga as the sister group to those two, and Archostemata as sister to the other three collectively. There are about 350,000 species of beetles. Such a large number of species poses special problems for classification, with some families consisting of thousands of species and needing further division into subfamilies and tribes. Pests. Many agricultural, forestry, and household insect pests are beetles. These include the following: Beneficial organisms. Some farmers develop beetle banks to foster and provide cover for beneficial beetles. Beetles of the Dermestidae family are often used in taxidermy to clean bones of remaining flesh. Beetles in ancient Egypt and other cultures. Several species of dung beetle, most notably "Scarabaeus sacer" (often referred to as "scarab"), enjoyed a sacred status among the ancient Egyptians, as the creatures were likened to the major god Khepri. Some scholars suggest that the Egyptians' practice of making mummies was inspired by the brooding process of the beetle. Many thousands of amulets and stamp seals have been excavated that depict the scarab. In many artifacts, the scarab is depicted pushing the sun along its course in the sky, much as scarabs push or roll balls of dung to their brood sites. During and following the New Kingdom, scarab amulets were often placed over the heart of the mummified deceased. Some tribal groups, particularly in tropical parts of the world, use the colourful, iridescent elytra of certain beetles, especially certain Scarabaeidae, in ceremonies and as adornment. Study and collection. The study of beetles is called coleopterology'" (from "Coleoptera", see above, and Greek, "-logia"), and its practitioners are "coleopterists" (see this list). Coleopterists have formed organisations to facilitate the study of beetles. Among these is The Coleopterists Society, an international organisation based in the United States. Such organisations may have both professionals and amateurs interested in beetles as members. Research in this field is often published in peer-reviewed journals specific to the field of coleopterology, though journals dealing with general entomology also publish many papers on various aspects of beetle biology. Some of the journals specific to beetle research are: There is a thriving industry in the collection of beetle specimens for amateur and professional collectors. Many coleopterists prefer to collect beetle specimens for themselves, recording detailed information about each specimen and its habitat. Such collections add to the body of knowledge about the Coleoptera. Some countries have established laws governing or prohibiting the collection of certain rare (and often much sought after) species. One such beetle whose collection is illegal or restricted is the American burying beetle, "Nicrophorus americanus".	An automobile'" or "'motor car'" is a wheeled motor vehicle for transporting passengers, which also carries its own engine or motor. Most definitions of the term specify that automobiles are designed to run primarily on roads, to have seating for one to eight people, to typically have four wheels, and to be constructed principally for the transport of people rather than goods. However, the term "automobile" is far from precise, because there are many types of vehicles that do similar tasks. As of 2002, there were 590 million passenger cars worldwide (roughly one car per eleven people). Etymology. The word automobile'" comes, via the French "automobile", from the Ancient Greek word αὐτός ("autós", "self") and the Latin "mobilis" ("movable"); meaning a vehicle that moves itself, rather than being pulled or pushed by a separate animal or another vehicle. The alternative name "car" is believed to originate from the Latin word "carrus" or "carrum" ("wheeled vehicle"), or the Middle English word "carre" ("cart") (from Old North French), or "karros" (a Gallic wagon). History. Although Nicolas-Joseph Cugnot is often credited with building the first self-propelled mechanical vehicle or automobile in about 1769 by adapting an existing horse-drawn vehicle, this claim is disputed by some, who doubt Cugnot's three-wheeler ever ran or was stable. Ferdinand Verbiest, a member of a Jesuit mission in China, built the first steam-powered vehicle around 1672 which was of small scale and designed as a toy for the Chinese Emperor that was unable to carry a driver or a passenger, but quite possibly, was the first working steam-powered vehicle ('auto-mobile'). What is not in doubt is that Richard Trevithick built and demonstrated his "Puffing Devil" road locomotive in 1801, believed by many to be the first demonstration of a steam-powered road vehicle although it was unable to maintain sufficient steam pressure for long periods, and would have been of little practical use. In Russia, in the 1780s, Ivan Kulibin developed a human-pedalled, three-wheeled carriage with modern features such as a flywheel, brake, gear box, and bearings; however, it was not developed further. François Isaac de Rivaz, a Swiss inventor, designed the first internal combustion engine, in 1806, which was fueled by a mixture of hydrogen and oxygen and used it to develop the world's first vehicle, albeit rudimentary, to be powered by such an engine. The design was not very successful, as was the case with others such as Samuel Brown, Samuel Morey, and Etienne Lenoir with his hippomobile, who each produced vehicles (usually adapted carriages or carts) powered by clumsy internal combustion engines. In November 1881 French inventor Gustave Trouvé demonstrated a working three-wheeled automobile that was powered by electricity. This was at the International Exhibition of Electricity in Paris. Although several other German engineers (including Gottlieb Daimler, Wilhelm Maybach, and Siegfried Marcus) were working on the problem at about the same time, Karl Benz'" generally is acknowledged as the inventor of the modern automobile. An automobile powered by his own four-stroke cycle gasoline engine was built in Mannheim, Germany by Karl Benz in 1885 and granted a patent in January of the following year under the auspices of his major company, Benz & Cie., which was founded in 1883. It was an integral design, without the adaptation of other existing components and including several new technological elements to create a new concept. This is what made it worthy of a patent. He began to sell his production vehicles in 1888. In 1879 Benz was granted a patent for his first engine, which had been designed in 1878. Many of his other inventions made the use of the internal combustion engine feasible for powering a vehicle. His first "Motorwagen" was built in 1885 and he was awarded the patent for its invention as of his application on January 29, 1886. Benz began promotion of the vehicle on July 3, 1886 and approximately 25 Benz vehicles were sold between 1888 and 1893, when his first four-wheeler was introduced along with a model intended for affordability. They also were powered with four-stroke engines of his own design. Emile Roger of France, already producing Benz engines under license, now added the Benz automobile to his line of products. Because France was more open to the early automobiles, initially more were built and sold in France through Roger than Benz sold in Germany. In 1896, Benz designed and patented the first internal-combustion flat engine, called a "boxermotor" in German. During the last years of the nineteenth century, Benz was the largest automobile company in the world with 572 units produced in 1899 and because of its size, Benz & Cie., became a joint-stock company. Daimler and Maybach founded Daimler Motoren Gesellschaft (Daimler Motor Company, DMG) in Cannstatt in 1890 and under the brand name, "Daimler", sold their first automobile in 1892, which was a horse-drawn stagecoach built by another manufacturer, that they retrofitted with an engine of their design. By 1895 about 30 vehicles had been built by Daimler and Maybach, either at the Daimler works or in the Hotel Hermann, where they set up shop after falling out with their backers. Benz and the Maybach and Daimler team seem to have been unaware of each other's early work. They never worked together because by the time of the merger of the two companies, Daimler and Maybach were no longer part of DMG. Daimler died in 1900 and later that year, Maybach designed an engine named "Daimler-Mercedes", that was placed in a specially-ordered model built to specifications set by Emil Jellinek. This was a production of a small number of vehicles for Jellinek to race and market in his country. Two years later, in 1902, a new model DMG automobile was produced and the model was named Mercedes after the Maybach engine which generated 35 hp. Maybach quit DMG shortly thereafter and opened a business of his own. Rights to the "Daimler" brand name were sold to other manufacturers. Karl Benz proposed co-operation between DMG and Benz & Cie. when economic conditions began to deteriorate in Germany following the First World War, but the directors of DMG refused to consider it initially. Negotiations between the two companies resumed several years later when these conditions worsened and, in 1924 they signed an "Agreement of Mutual Interest", valid until the year 2000. Both enterprises standardized design, production, purchasing, and sales and they advertised or marketed their automobile models jointly—although keeping their respective brands. On June 28, 1926, Benz & Cie. and DMG finally merged as the "Daimler-Benz" company, baptizing all of its automobiles "Mercedes Benz" as a brand honoring the most important model of the DMG automobiles, the Maybach design later referred to as the "1902 Mercedes-35hp", along with the Benz name. Karl Benz remained a member of the board of directors of Daimler-Benz until his death in 1929 and at times, his two sons participated in the management of the company as well. In 1890, Emile Levassor and Armand Peugeot of France began producing vehicles with Daimler engines and so laid the foundation of the automobile industry in France. The first design for an American automobile with a gasoline internal combustion engine was drawn in 1877 by George Selden of Rochester, New York, who applied for a patent for an automobile in 1879, but the patent application expired because the vehicle was never built and proved to work (a requirement for a patent). After a delay of sixteen years and a series of attachments to his application, on November 5, 1895, Selden was granted a United States patent for a two-stroke automobile engine, which hindered, more than encouraged, development of automobiles in the United States. His patent was challenged by Henry Ford and others, and overturned in 1911. In Britain there had been several attempts to build steam cars with varying degrees of success with Thomas Rickett even attempting a production run in 1860. Santler from Malvern is recognized by the Veteran Car Club of Great Britain as having made the first petrol-powered car in the country in 1894 followed by Frederick William Lanchester in 1895 but these were both one-offs. The first production vehicles in Great Britain came from the Daimler Motor Company, a company founded by Harry J. Lawson in 1896 after purchasing the right to use the name of the engines. Lawson's company made its first automobiles in 1897 and they bore the name "Daimler". In 1892, German engineer Rudolf Diesel was granted a patent for a "New Rational Combustion Engine". In 1897 he built the first Diesel Engine. Steam-, electric-, and gasoline-powered vehicles competed for decades, with gasoline internal combustion engines achieving dominance in the 1910s. Although various pistonless rotary engine designs have attempted to compete with the conventional piston and crankshaft design, only Mazda's version of the Wankel engine has had more than very limited success. Production. The large-scale, production-line manufacturing of affordable automobiles was debuted by Ransom Olds at his Oldsmobile factory in 1902. This concept was greatly expanded by Henry Ford, beginning in 1914. As a result, Ford's cars came off the line in fifteen minute intervals, much faster than previous methods, increasing productivity eight fold (requiring 12.5 man-hours before, 1 hour 33 minutes after), while using less manpower. It was so successful, paint became a bottleneck. Only Japan black would dry fast enough, forcing the company to drop the variety of colors available before 1914, until fast-drying Duco lacquer was developed in 1926. This is the source of Ford's apocryphal remark, "any color as long as it's black". In 1914, an assembly line worker could buy a Model T with four months' pay. Ford's complex safety procedures—especially assigning each worker to a specific location instead of allowing them to roam about—dramatically reduced the rate of injury. The combination of high wages and high efficiency is called "Fordism," and was copied by most major industries. The efficiency gains from the assembly line also coincided with the economic rise of the United States. The assembly line forced workers to work at a certain pace with very repetitive motions which led to more output per worker while other countries were using less productive methods. In the automotive industry, its success was dominating, and quickly spread worldwide seeing the founding of Ford France and Ford Britain in 1911, Ford Denmark 1923, Ford Germany 1925; in 1921, Citroen was the first native European manufacturer to adopt the production method. Soon, companies had to have assembly lines, or risk going broke; by 1930, 250 companies which did not, had disappeared. Development of automotive technology was rapid, due in part to the hundreds of small manufacturers competing to gain the world's attention. Key developments included electric ignition and the electric self-starter (both by Charles Kettering, for the Cadillac Motor Company in 1910-1911), independent suspension, and four-wheel brakes. Since the 1920s, nearly all cars have been mass-produced to meet market needs, so marketing plans often have heavily influenced automobile design. It was Alfred P. Sloan who established the idea of different makes of cars produced by one company, so buyers could "move up" as their fortunes improved. Reflecting the rapid pace of change, makes shared parts with one another so larger production volume resulted in lower costs for each price range. For example, in the 1930s, LaSalles, sold by Cadillac, used cheaper mechanical parts made by Oldsmobile; in the 1950s, Chevrolet shared hood, doors, roof, and windows with Pontiac; by the 1990s, corporate drivetrains and shared platforms (with interchangeable brakes, suspension, and other parts) were common. Even so, only major makers could afford high costs, and even companies with decades of production, such as Apperson, Cole, Dorris, Haynes, or Premier, could not manage: of some two hundred American car makers in existence in 1920, only 43 survived in 1930, and with the Great Depression, by 1940, only 17 of those were left. In Europe much the same would happen. Morris set up its production line at Cowley in 1924, and soon outsold Ford, while beginning in 1923 to follow Ford's practise of vertical integration, buying Hotchkiss (engines), Wrigley (gearboxes), and Osberton (radiators), for instance, as well as competitors, such as Wolseley: in 1925, Morris had 41% of total British car production. Most British small-car assemblers, from Abbey to Xtra had gone under. Citroen did the same in France, coming to cars in 1919; between them and other cheap cars in reply such as Renault's 10CV and Peugeot's 5CV, they produced 550,000 cars in 1925, and Mors, Hurtu, and others could not compete. Germany's first mass-manufactured car, the Opel 4PS "Laubfrosch" (Tree Frog), came off the line at Russelsheim in 1924, soon making Opel the top car builder in Germany, with 37.5% of the market. Fuel and propulsion technologies. Most automobiles in use today are propelled by gasoline (also known as petrol) or diesel internal combustion engines, which are known to cause air pollution and are also blamed for contributing to climate change and global warming. Increasing costs of oil-based fuels, tightening environmental laws and restrictions on greenhouse gas emissions are propelling work on alternative power systems for automobiles. Efforts to improve or replace existing technologies include the development of hybrid vehicles, and electric and hydrogen vehicles which do not release pollution into the air. Diesel. Diesel-engined cars have long been popular in Europe with the first models being introduced in the 1930s by Mercedes Benz and Citroen. The main benefit of diesel engines is a 50% fuel burn efficiency compared with 27% in the best gasoline engines. A down-side of the Diesel engine is that better filters are required to reduce the presence in the exhaust gases of fine soot particulates called diesel particulate matter. Manufacturers are now starting to fit diesel particulate filters to remove the soot. Many diesel-powered cars can run with little or no modifications on 100% biodiesel and combinations of other organic oils. Gasoline. Gasoline engines have the advantage over diesel in being lighter and able to work at higher rotational speeds and they are the usual choice for fitting in high-performance sports cars. Continuous development of gasoline engines for over a hundred years has produced improvements in efficiency and reduced pollution. The carburetor was used on nearly all road car engines until the 1980s but it was long realised better control of the fuel air mixture could be achieved with fuel injection. Indirect fuel injection was first used in aircraft engines from 1909, in racing car engines from the 1930s, and road cars from the late 1950s. Gasoline Direct Injection (GDI) is now starting to appear in production vehicles such as the 2007 (Mark II) BMW Mini. Exhaust gases are also cleaned up by fitting a catalytic converter into the exhaust system. Clean air legislation in many of the car industries most important markets has made both catalysts and fuel injection virtually universal fittings. Most modern gasoline engines also are capable of running with up to 15% ethanol mixed into the gasoline; older vehicles may have seals and hoses that can be harmed by ethanol. With a small amount of redesign, gasoline-powered vehicles can run on ethanol concentrations as high as 85%. 100% ethanol is used in some parts of the world (such as Brazil), but vehicles must be started on pure gasoline and switched over to ethanol once the engine is running. Most gasoline engined cars can also run on LPG with the addition of an LPG tank for fuel storage and carburettor modifications to add an LPG mixer. LPG produces fewer toxic emissions and is a popular fuel for fork-lift trucks that have to operate inside buildings. Biofuels. Ethanol, other alcohol fuels (biobutanol) and biogasoline have widespread use an automotive fuel. Most alcohols have less energy per liter than gasoline and are usually blended with gasoline. Alcohols are used for a variety of reasons: to increase octane, to improve emissions, and as an alternative to petroleum based fuel, since they can be made from agricultural crops. Brazil's ethanol program provides about 20% of the nation's automotive fuel needs, as a result of the mandatory use of E25 blend of gasoline throughout the country, 3 million cars that operate on pure ethanol, and 6 million dual or flexible-fuel vehicles sold since 2003. that run on any mix of ethanol and gasoline. The commercial success of "flex" vehicles, as they are popularly known, have allowed sugarcane based ethanol fuel to achieve a 50% market share of the gasoline market by April 2008. Electric. The first electric cars were built around 1832, well before internal combustion powered cars appeared. For a period of time electrics were considered superior due to the silent nature of electric motors compared to the very loud noise of the gasoline engine. This advantage was removed with Hiram Percy Maxim's invention of the muffler in 1897. Thereafter internal combustion powered cars had two critical advantages: 1) long range and 2) high specific energy (far lower weight of petrol fuel versus weight of batteries). The building of battery electric vehicles that could rival internal combustion models had to wait for the introduction of modern semiconductor controls and improved batteries. Because they can deliver a high torque at low revolutions electric cars do not require such a complex drive train and transmission as internal combustion powered cars. Some post-2000 electric car designs such as the Venturi Fétish are able to accelerate from 0-60 mph (96 km h) in 4.0 seconds with a top speed around 130 mph (210 km h). Others have a range of 250 miles (400 km) on the United States Environmental Protection Agency‎ (EPA) highway cycle requiring 31 2 hours to completely charge. Equivalent fuel efficiency to internal combustion is not well defined but some press reports give it at around. Steam. Steam power, usually using an oil- or gas-heated boiler, was also in use until the 1930s but had the major disadvantage of being unable to power the car until boiler pressure was available (although the newer models could achieve this in well under a minute). It has the advantage of being able to produce very low emissions as the combustion process can be carefully controlled. Its disadvantages include poor heat efficiency and extensive requirements for electric auxiliaries.. Air. A compressed air car is an alternative fuel car that uses a motor powered by compressed air. The car can be powered solely by air, or by air combined (as in a hybrid electric vehicle) with gasoline diesel ethanol or electric plant and regenerative braking. Instead of mixing fuel with air and burning it to drive pistons with hot expanding gases; "compressed air cars" use the expansion of compressed air to drive their pistons. Several prototypes are available already and scheduled for worldwide sale by the end of 2008, though this has not happened as of January 2009. Companies releasing this type of car include Tata Motors and Motor Development International (MDI). Gas turbine. In the 1950s there was a brief interest in using gas turbine engines and several makers including Rover and Chrysler produced prototypes. In spite of the power units being very compact, high fuel consumption, severe delay in throttle response, and lack of engine braking meant no cars reached production. Rotary (Wankel) engines. Rotary Wankel engines were introduced into road cars by NSU with the Ro 80 and later were seen in the Citroën GS Birotor and several Mazda models. In spite of their impressive smoothness, poor reliability and fuel economy led to them largely disappearing. Mazda, beginning with the R100 then RX-2, has continued research on these engines, overcoming most of the earlier problems with the RX-7 and RX-8. Rocket and jet cars. A rocket car holds the record in drag racing. However, the fastest of those cars are used to set the Land Speed Record, and are propelled by propulsive jets emitted from rocket, turbojet, or more recently and most successfully turbofan engines. The ThrustSSC car using two Rolls-Royce Spey turbofans with reheat was able to exceed the speed of sound at ground level in 1997. Safety. There are three main statistics to which automobile safety can be compared: While road traffic injuries represent the leading cause in worldwide injury-related deaths, their popularity undermines this statistic. Mary Ward became one of the first documented automobile fatalities in 1869 in Parsonstown, Ireland and Henry Bliss one of the United States' first pedestrian automobile casualties in 1899 in New York. There are now standard tests for safety in new automobiles, like the EuroNCAP and the US NCAP tests, as well as insurance-backed IIHS tests. Costs and benefits. The costs of automobile usage, which may include the cost of: acquiring the vehicle, repairs, maintenance, fuel, depreciation, parking fees, tire replacement, taxes and insurance, are weighed against the cost of the alternatives, and the value of the benefits, perceived and real, of vehicle usage. The benefits may include on-demand transportation, mobility, independence and convenience. Similarly the costs to society of encompassing automobile use, which may include those of: maintaining roads, land use, pollution, public health, health care, and of disposing of the vehicle at the end of its life, can be balanced against the value of the benefits to society that automobile use generates. The societal benefits may include: economy benefits, such as job and wealth creation, of automobile production and maintenance, transportation provision, society wellbeing derived from leisure and travel opportunities, and revenue generation from the opportunities. The ability for humans to move flexibly from place to place has far reaching implications for the nature of societies. Environmental impact. Transportation is a major contributor to air pollution in most industrialised nations. According to the American Surface Transportation Policy Project nearly half of all Americans are breathing unhealthy air. Their study showed air quality in dozens of metropolitan areas has got worse over the last decade. In the United States the average passenger car emits 11,450 lbs (5 tonnes) of carbon dioxide, along with smaller amounts of carbon monoxide, hydrocarbons, and nitrogen. Residents of low-density, residential-only sprawling communities are also more likely to die in car collisions, which kill 1.2 million people worldwide each year, and injure about forty times this number. Sprawl is more broadly a factor in inactivity and obesity, which in turn can lead to increased risk of a variety of diseases. Other species are often negatively impacted by automobiles via habitat destruction and pollution. Over the lifetime of the average automobile the "loss of habitat potential" may be over 50,000 square meters (538,195 square feet) based on Primary production correlations. Fuel taxes may act as an incentive for the production of more efficient, hence less polluting, car designs (e.g. hybrid vehicles) and the development of alternative fuels. High fuel taxes may provide a strong incentive for consumers to purchase lighter, smaller, more fuel-efficient cars, or to not drive. On average, today's automobiles are about 75 percent recyclable, and using recycled steel helps reduce energy use and pollution. In the United States Congress, federally mandated fuel efficiency standards have been debated regularly, passenger car standards have not risen above the standard set in 1985. Light truck standards have changed more frequently, and were set at in 2007. Alternative fuel vehicles are another option that is less polluting than conventional petroleum powered vehicles. Future car technologies. Automobile propulsion technology under development include electric and plug-in hybrids, battery electric vehicles, hydrogen cars, biofuels, and various alternative fuels. Research into future alternative forms of power include the development of fuel cells, Homogeneous Charge Compression Ignition (HCCI), stirling engines, and even using the stored energy of compressed air or liquid nitrogen. New materials which may replace steel car bodies include duraluminum, fiberglass, carbon fiber, and carbon nanotubes. Telematics technology is allowing more and more people to share cars, on a pay-as-you-go basis, through such schemes as City Car Club in the UK, Mobility in mainland Europe, and Zipcar in the US. Alternatives to the automobile. Established alternatives for some aspects of automobile use include public transit (buses, trolleybuses, trains, subways, monorails, tramways), cycling, walking, rollerblading, skateboarding, horseback riding and using a velomobile. Car-share arrangements and carpooling are also increasingly popular–the U.S. market leader in car-sharing has experienced double-digit growth in revenue and membership growth between 2006 and 2007, offering a service that enables urban residents to "share" a vehicle rather than own a car in already congested neighborhoods. Bike-share systems have been tried in some European cities, including Copenhagen and Amsterdam. Similar programs have been experimented with in a number of U.S. Cities. Additional individual modes of transport, such as personal rapid transit could serve as an alternative to automobiles if they prove to be socially accepted.