Dog

This allows them to be trained to behave in a way that is not specifically the most natural to their breed; nevertheless, the accumulated experience of thousands of years shows that some combinations of nature and nurture are quite daunting, for instance, training whippets to guard flocks of sheep. A number of formal and industry standards exist for bicycle components, to help make spare parts exchangeable:. Of course, dogs in general possess a significant ability to modify their behavior according to experience, including adapting to the behavior of their "pack leaders"—again, humans. Another bicycle rented to tourists in Berlin carries eight people seated in a circle. The example of canine neoteny goes even further, in that the various breeds are differently neotenized according to the type of behavior that was selected. in the 1890s. Compared to wolves, many adult dog breeds retain such juvenile characteristics as soft fuzzy fur, round torsos, large heads and eyes, ears that hang down rather than stand erect, etc.; characteristics which are shared by most juvenile mammals, and therefore generally elicit some degree of protective and nurturing behavior cross-species from most adult mammals, including humans, who term such characteristics "cute" or "appealing". Y.

This paedomorphic selection naturally results in a retention of juvenile physical characteristics as well. in Rochester, N. This is true of many domesticated animals, including human beings themselves, who have many characteristics similar to young bonobo. Co. As with many species, the young wolves are more social and less dominant than adults; therefore, the selection for these characteristics, whether deliberate or inadvertent, is more likely to result in a simple retention of juvenile characteristics into adulthood than to generate a complex of independent new changes in behavior. Exceptions are "The Companion", or "sociable," a side-by-side two-person bike (that converted to a single-rider) built by the Punnett Cycle Mfg. This rapid evolution of dogs from wolves is an example of neoteny or paedomorphism. In most of these types the riders ride one behind the other.

Deliberately crossing two or more breeds is also a manner of establishing new breeds. See also Category:Cycle types. However, without genetic testing of the parents, the crosses can sometimes end up inheriting genetic defects that occur in both parental breeds. There are many different types of bicycle. Such deliberate crosses may display hybrid vigor and other desirable traits, but can also lack one or more of the desired traits of their parents, such as temperament or a particular color or coat. According to participants in Critical Mass, "We aren't blocking traffic, we are traffic!" However, their particular forms of protest has drawn criticism from the broader streams of activism. Sometimes mixed-breed dogs are deliberately bred, for example, the Cockapoo, a mixture of Cocker Spaniel and Miniature Poodle. It incorporates the themes of increasing the road- and mind-share given to bicycle transport, and has drawn support from environmentally minded campaigners and other schools of political thought.

Mixed breeds, or dogs with no purebred ancestry, are not inherently "better" or "worse" than purebred dogs as companions, pets, working dogs, or competitors in dog sports. Critical Mass is a worldwide activist movement of mass bicycle protest rides. Mixed-breed dogs or Mongrels are dogs that do not belong to specific breeds, being mixtures of two or more in variant percentages. As a consequence, activists from both sides have put aside their differences in order to fight the helmet lobby. In February 2004, the Canine Studies Institute in Aurora, Ohio, arranged recognized breeds of dogs into ten categories. They cite evidence suggesting that compulsory helmet laws and helmet promotion have been associated with significant reductions in bicycle use and with increases in the risk of death or injury to individual cyclists. The behavior and appearance of a dog of a particular breed can be predicted fairly accurately, while mixed-breed dogs show a broader range of innovative appearance and behavior. A recent focus, especially for European bicycle activists, has been opposition to compulsory bicycle helmet legislation.

These problems are not limited to purebred dogs and can affect mixed-breed populations. This is part of the ongoing cycle path debate. Even prize-winning purebred dogs sometimes possess crippling genetic defects due to inbreeding. Some groups offer training courses to help cyclists integrate themselves with other traffic. These considerations come into play among breeders who enter their dogs in dog shows. In some cases this opposition has a more ideological basis: some members of the Vehicular Cycling movement oppose segregated public facilities, such as on-street bike lanes, on principle. Other organizations define a breed more loosely, such that an individual may be considered of one breed as long as 75% of its parentage is of that breed. They favour a more holistic approach based on the 4 'E's; education (of everyone involved), encouragement (to apply the education), enforcement (to protect the rights of others), and engineering (to facilitate travel while respecting every person's equal right to do so).

Dogs that are bred in this manner often end up with severe health or behavioural problems. Other activists, especially those from the more established tradition, view the safety, practicality, and intent of many segregated cycle facilities with suspicion. Some groups use a definition that ultimately requires extreme inbreeding to qualify due to the low gene pool. Controversially, some bicycle activists (including some traffic management advisors) seek the construction of segregated cycle facilities for journeys of all lengths. The definition of a dog breed is a matter of some controversy. Many cities also have community bicycle programs that promote cycling, especially as a means of inner-city transport. Despite these differences, dogs are able to distinguish dogs from other kinds of animal. Activists in both camps also argue for improved local and inter-city rail services and other methods of mass transportation, and also for greater provision for cycle carriage on such services.

Because of this, some breeds are highly specialized, and there is extraordinary morphological diversity across different breeds. Such groups promote the bicycle as an alternative mode of transport and emphasize the potential for energy and resource conservation and health benefits gained from cycling versus automobile use. Many of these are the product of a deliberate process of artificial selection. Two broad themes run in bicycle activism: one more overtly political with roots in the environmental movement; the other drawing on the traditions of the established bicycle lobby. A few basic breed types have evolved gradually during the domesticated dog's relationship with man over the last 10,000 or more years, but most modern breeds are of relatively recent derivation. Cyclists form associations, both for specific interests (trails development, road maintenance, urban design, racing clubs, touring clubs, etc.) and for more global goals (energy conservation, pollution reduction, promotion of fitness). Many dogs, especially outside the United States and Western Europe, belong to no recognized breed. Studies have demonstrated that, due to the high incidence of accidents at these sites, such segregated schemes can actually increase the number of car-bike collisions.⁷.

As all dog breeds have been derived from mixed-breed dog populations, the term "purebred" has meaning only with respect to a certain number of generations. At some point the two streams of traffic inevitably intersect, often in a haphazard and congested fashion. There are numerous dog breeds, over 800 being recognized by various kennel clubs worldwide. Segregating bicycle and automobile traffic in cities has met with mixed success, both in terms of safety and bicycle promotion. In a number of countries around the world, apart from being kept as pets, certain breeds of dogs are slaughtered as a source of meat and specifically raised on farms for that purpose. Such dedicated paths often have to be shared with inline skaters, scooters, skateboarders, and pedestrians. The relationship is theorized to have developed in this way. Extensive bicycle path systems may be found in some cities.

With their sharp senses, they would also be valuable as an alarm against marauding predators. Conversely, an absence of secure cycle-parking is a recurring complaint by cyclists from cities with low modal share of cycling. Canines would have been beneficial by chasing away other vermin or scavengers. Local governments also promote cycling by permitting the carriage of bicycles on public transport or by providing external attachment devices on public transport vehicles. Canines who attacked people or their children were likely killed or driven away, while those more friendly animals survived. In areas in which cycling is popular and encouraged, cycle-parking facilities using bicycle racks, lockable mini-garages, and patrolled cycle parks are used to reduce theft. Wild canines who scavenged around human habitations received more food than their more skittish or fearful counterparts. In Shanghai, a city where bicycles were once the dominant mode of transportation, bicycle travel on city roads was actually banned temporarily in December 2003.

It is also now generally believed that initial domestication was through mutual desire. Occasionally, extreme measures against cycling may occur. Domestication of a wild dog may occur within one or two human generations with deliberate selective breeding. In the former cases, cycling has tended to decline while in the latter it has tended to be maintained. Current research indicates that domestication, or the attributes of a domesticated animal, can occur much more quickly than previously believed. Other cities may apply active traffic restraint measures to limit the impact of motorised transport. While some dog breeds possess one of these characteristics, they rarely possess both. Some jurisdictions give priority to motorised traffic, for example setting up extensive one-way street systems, free-right turns, high capacity roundabouts, and slip roads.

Wolves typically have a "brush tail" and erect ears. Cyclists and motorists make different demands on road design which may lead to conflicts both in politics and on the streets. The phenotypic characteristic that distinguish a wolf from a dog are tenuous. monocoque frames, such as used by Chris Boardman to win the Gold medal in 1992 Olympic individual pursuit event in Barcelona, were no longer permitted. The general reproductive isolation which is required to define dogs and wolves as separate species is purely a result of lack of opportunity, stemming from a general mutual unfamiliarity, suspicion, mistrust, and fear. For example. Additionally, unintentional crossbreeding occurs simply because dogs and wolves live in the same environment. Their stated motive was so that developing countries could compete in international competitions without requiring large equipment budgets, and to re-focus attention on the athlete rather than the bicyle.

This interbreeding still occurs with dogs living in the Arctic region, where the attributes of the wolf that enable survival in a hostile environment are valued by humans. These rules met with considerable controversy and to some extent arrested the development of the racing bicycle. The Eastern Timber Wolf is a direct ancestor to most, if not all, of the North American northern sled dog types. The governing body of international cycle sport, the Union Cycliste International, decided in the late 1990s to create additional rules restricting the design of racing bicycles. The Chinese wolf is probably ancestor to the Pekingese and toy spaniels, although it is also probable that descendants of the Chinese and European wolves encountered each other over the millennia, contributing to many of the oriental toy breeds. In the past decade, mountain bike racing has also reached international popularity and is even an Olympic sport. The European wolf, in turn, may have contributed many of its attributes to the Spitz dog types, most terriers, and many of today's sheepdogs. Track bicycles are used for track racing in Velodromes , while cyclo-cross races are held on rugged outdoor terrain.

The Tibetan Mastiff is an example of an ancient breed. Recumbent bicycles were banned from bike races in 1934 after Marcel Berthet set a new hour record in his Velodyne streamliner (49.992 km on Nov 18, 1933). The Indian wolf is also thought to have bred with descendants of the European wolf to create the Mastiffs and eventually leading to the development of such diverse breeds as the Pug, the Saint Bernard, and the Bloodhound. They range from the one-day road race, criterium, and time trial to multi-stage events like the Tour de France and its sister events which make up cycling's Grand Tours. Many of today's wild dogs, such as the dingo, the dhole and pariah dogs, are descended from this wolf. Road races may involve both team and individual competition, and are contested in various ways. The Indian Wolf is thought to have contributed to the development of more breeds of dogs than other subspecies. As the bicycle evolved its various forms, different racing formats developed.

For example, the Japanese wolf and the Eastern Timber Wolf posses different distinctive colouration, hunting and social structures. This began in 1903, and continues to capture the attention of the sporting world. Although all wolves belong to the species Canis lupus, there are (or were) many subspecies that had developed a distinctive appearance, social structure, and other traits. The most famous of all bicycle races is the Tour de France. The detailed history remains unexplored and until further evidence is available, the following section on wolf ancestors must be considered purely speculative. However since the middle of the 20th Century cycling has become a minority sport in the US whilst in Continental Europe it continues to be a major sport, particulrly in France, Belgium and Italy. Their results indicate multiple independent origins of dogs and/or of frequent interbreeding between early proto-dogs and wolves throughout a vast geographic range. At one point, almost every major city in the US had a velodrome or two for track racing events.

Verginelli examined ancient DNA evidence from five prehistoric Italian canids carbon-dated to between 15,000 and 3,000 years old, 341 wolves from several populations worldwide, and 547 purebred dogs. and Japan as well. On balance, and in agreement with the archaeological evidence, 15,000 years ago is the most likely time for the wolf-dog divergence. Large races became popular during the 1890's "Golden Age of Cycling", with events across Europe, and in the U.S. (2005), however, suggest both sets of dates must be reevaluated in light of recent findings showing that poorly calibrated molecular clocks have systematically overestimated the age of geologically recent events. Early races involving boneshaker style bicycles were predictably fraught with injuries. Verginelli et al. Shortly after the introduction of bicycles, competitions developed independently in many parts of the world.

(2002) indicated a "common origin from a single gene pool for all dog populations" between 40,000 and 15,000 years ago in East Asia. The only country to recently maintain a regiment of bicycle troops was Switzerland, who disbanded the last unit in 2003. Vilà, Savolainen, and colleagues (1997) concluded that dogs split off from wolves between 75,000 and 135,000 years ago, while a subsequent analysis by Savolainen et al. invasion of Afghanistan and in subsequent battles against the Taliban. Genetic analyses have so far yielded divergent results. Special Forces in the U.S. Dog burials at the Mesolithic cemetery of Svaerdborg in Denmark suggest that in ancient Europe dogs were valued companions. There are reports of mountain bicycles being used in scouting by U.S.

Rock art and skeletal remains indicate that by 14,000 years ago, dogs were present from North Africa across Eurasia to North America. In the Vietnam War, communist forces used bicycles extensively as cargo carriers along the Ho Chi Minh Trail. Remains of smaller dogs from Mesolithic (Natufian) cave deposits in the Middle East, dated to around 12,000 years ago, have been interpreted as descendants of a lighter Southwest Asian wolf, Canis lupus arabs. Germany used bicycles again in World War II, while the British employed airborne Cycle-commandos with folding bikes. Their likely ancestor is the large northern Holarctic wolf, Canis lupus lupus. In its 1937 invasion of China, Japan employed some 50,000 bicycle troops, and similar forces were instrumental in Japan's march through Malaya in World War II. The earliest dog fossils, two crania from Russia and a mandible from Germany, date from 13,000 to 17,000 years ago. In World War I, France and Germany used bicycles to move troops.

Domesticated dogs may have interbred with local populations of wild wolves on several occasions (so-called introgression). Bicycles were used in the Second Boer War, where both sides used them for scouting. Fossil bone morphologies and genetic analysis of current and ancient dog and wolf populations have not yet been able to conclusively determine whether all dogs descend from a single domestication event, or whether dogs were domesticated independently in more than one location. The bicycle is not suited for combat, but it has been used as a method of transporting soldiers and supplies to combat zones. Converging archaeological and genetic evidence indicate a time of domestication in the late Upper Paleolithic close to the Pleistocene/Holocene boundary, between 17,000 and 14,000 years ago. Paris-Brest-Paris (PBP), which began in 1891, is the oldest bicycling event still run on a regular basis on the open road, covers over 1200 km and imposes a 90-hour time limit. Wolf remains have been found in association with hominid remains dating from 400,000 years ago. Many Dutch people subscribe every year to an event called fietsvierdaagse — four days of organised cycling through the local environment.

The relationship between man and canine has deep roots. The land is very flat and full of special public bicycle trails where cyclist aren't bothered by cars and other traffic, which makes it ideal for cycling recreation. As reflected in the nomenclature, dogs are a subspecies of wolf and are thus still able to interbreed. One major aspect of Dutch popular culture is enjoying relaxed cycling in the countryside of the Netherlands. Molecular systematics indicate that the domestic dog (Canis lupus familiaris) descends from one or more populations of wild wolves (Canis lupus). A brevet or randonnée is an organized long-distance ride. In the UK, it is illegal to kill dogs, even if they are on your private land; you are required to contact your local Police Force, DogsTrust, or the local branch of the RSPCA, who will arrange its collection. Bicycle touring involves touring and exploration or sightseeing with the use of a bicycle for leisure.

Feral dogs often form predatory packs that attack livestock and occasionally also prove dangerous to humans. Bicycles are used for recreation at all ages. Abandoned domestic dogs who become feral are particularly dangerous; they lack the survival skills of wild canines, as well as the genetic and learned fear of the humans' world. At the huge Mercedes-Benz factory in Sindelfingen, Germany workers use bicycles, colour-coded by department, to move around the factory. Bodies are sometimes tied to fences as warning to other dogs, especially in rural United States and Canada. Even the car industry uses bicycles. Wild dogs are shot by farmers in an effort to protect livestock. In Bogotá, Colombia the city’s largest bakery recently replaced most of its delivery trucks with bicycles.

The same creatures that wolves, coyotes, and foxes attack as prey, especially sheep and poultry, are similarly attractive prey to dogs. In India, many of Mumbai's Dabbawalas use bicycles to deliver hot lunches to the city’s workers. In most jurisdictions, dogs are destroyed for killing other creatures, so dogs should be prevented from any encounter with livestock or wildlife that might lead to a predatory response. In the UK, this use persisted for some purposes with generations of teenagers getting their first jobs delivering newspapers by bicycle. With formidable skills and weapons as hunters as well as large and unfussy appetites, dogs often menace livestock and wildlife. Bicycles have enjoyed substantial use as general delivery vehicles in many cities. Canine aggression upon humans is ordinarily not tolerated, but any human aggression against an animal having formidable means of self-defense is foolhardy in the extreme. The pursuit of suspects can also be assisted by a bicycle.

There are hundreds of shades of provocation that may or may not lead to an attack upon a human. They also have the advantages that the officers are inherently more open to the public, and the transport is quieter to permit a more stealthy approach toward suspects. Provocation can range from something as seemingly innocuous as a toddler pulling a dog's tail, in which case the dog might nip to discourage the behavior, to something completely inobvious to humans, such as an odor or a movement that sets a dog off, to blatant human aggression or violence towards a dog, causing it to defend itself. Bicycle patrols are now enjoying a resurgence in many cities, as the mobility of car-borne officers is becoming increasingly limited by traffic congestion and pedestrianisation. However, their sharp teeth and claws can inflict injury in an attack; a large dog can knock a human down. Some countries retained the police bicycle while others dispensed with them for a time. After thousands of years of domestication and selective breeding for dogs whose aggression towards humans goes no further than a ferocious bark that strongly indicates dislike of a human behavior, most dogs are unlikely to attack people. The Kent police purchased 20 bicycles in 1896, and by 1904 there were 129 police bicycle patrols operating.

Animals are often given attributes such as "loyal", "cute", and "guardian", but these all have the potential to lure people into a false sense of security. However, they eventually became a standard issue, particularly for police in rural areas. Humans have a tendency to anthropomorphize animals, particularly pets such as dogs, which are generally portrayed as being "man's best friend". Police officers adopted the bicycle as well, initially using their own. More research is needed to determine the intelligence level of dogs, and the motivations behind their responses to their masters. Bicycle delivery fleets include 37,000 in the UK, 25,700 in Germany and 10,500 in Hungary. Despite understandably positive interpretations by dog owners, it is questionable whether these animals are truly capable of feeling emotions on a human level. The Royal Mail first started using bicycles in 1880.

Nevertheless, it is often unwise to anthropomorphize the responses of dogs. The postal services of many countries have long relied on bicycles. Some research demonstrates that dogs are able to convey a depth of emotion not seen to the same extent in any other animal; this is purportedly due to their closely-knit development with modern man, and the survival-benefits of such communication as dogs became more dependent on humans for sustenance. One of the major reasons for the proliferation of Chinese-made bicycles in foreign markets is the increasing affordability of cars and motorcycles for its own citizens ⁵. Many dogs are reported to have separation anxiety if their owner is away for an extended period of time. Despite this shift in production, as nations such as China and India become more wealthy, their own use of bicycles has declined. Empirically, dogs are quite dependent on human companionship and may suffer poor health in its absence. Some sixty percent of the world's bicycles are now being made in China.

Many dog owners consider having unconditional acceptance from a friend who is always happy to see them to be quite utilitarian, particularly if the dog also leads them to regular exercise. In recent years, US and European bicycle makers have moved much of their production to Asia. Consequently, dogs are popular as pets and companions, independent of any utilitarian considerations. Both their model for political organization and the paved roads for which they argued facilitated the growth of the bicycle's rival, the automobile. Relationships between humans and dogs are often characterized by strong emotional bonds. In North America, the political organization of bicycle enthusiasts, in such groups as the League of American Wheelmen, led to further changes. Excitement is evident as they see the hunters load weapons, take to the field, and begin the hunt. They also reduced dependence on horses, and allowed people to travel into the country, since bicycles were three times as energy efficient as walking, and three to four times as fast.

Hunters with dogs report the satisfaction that the dogs seem to exhibit. In cities, bicycles helped reduce crowding in inner-city tenements by allowing workers to commute from single-family dwellings in the suburbs. Many hound breeds are excellent at treeing raccoons during hunting season. Sociologists suggest that bicycles enlarged the gene pool for rural workers, by enabling them to easily reach the next town and increase their courting radius. When trained, beagles are particularly adept at chasing through thick briars and brush after rabbits. The diamond-frame safety bicycle gave women unprecedented mobility, contributing to their emancipation in Western nations. They typically have large, gentle muzzles to mitigate any potential damage to the game. A British perfumer marketed Cycling Bouquet, which came in a tiny vial designed to fit into a lady cyclist's purse.

They can follow hand, verbal, and whistle commands at great distance as the hunter directs them to the downed bird. In the 1890s the cycling craze led to a new set of fashions, including bloomers, which helped liberate women from corsets and other restrictive clothing. At command, they dive into the icy water, swim out and retrieve the birds one by one. The evolution of the bicycle had less tangible effects as well, extending early to areas as diverse as fashion and politics. They can spend long hours in a duck blind and, after the hunter has fired at multiple ducks or geese, they can visually spot and remember the location of downed birds. In the United States, the League of American Wheelmen was a prominent advocate for the improvement of roads in the last part of the 19th century, founding and leading the national Good Roads Movement in the US. As water dogs, the retrievers are unsurpassed. Some bicycle clubs and national associations became prominent advocates for improvements to roads and highways.

Once the hunter approaches, at his command they will flush the birds to fly and for the hunter to shoot at. The Morris Motor Company and Škoda also began in the bicycle business, as did Henry Ford and the Wright Brothers. They have a native ability to discover and "hold" upland game birds; to freeze them momentarily on the ground with their silent, elongated pointing stance. Starley's company became the Rover Cycle Company Ltd. in the late 1890s, and then the Rover auto maker. Setters in particular have a long history as upland gun dogs. K. This often strengthens the bond between human and dog, since they must trust one another in a variety of environments and must learn how the other works and thinks. J.

Many people compete with their dogs in a variety of dog sports, including agility, flyball, and many others. These techniques later enabled skilled metalworkers and mechanics to develop the components used in early automobiles and aircraft. Dogs are also used for searching for or rescuing people and animals, such as in avalanches, at disaster sites, and for missing people or pets. Building modern bicycle frames led to the development of advanced metalworking techniques, both for the frames themselves and for special components such as ball bearings, washers, and sprockets. Most modern working dogs are put in positions which capitalize on their sensory or strength and endurance advantages over normal humans. Bicycle manufacturing proved to be a training ground for other industries. Dogs have served as guides for the blind, as commandos, and have flown into outer space. For more information on the technical aspects of bicycles, see also:.

There are service dogs, guard dogs, hunting dogs, and herding dogs. Speed changes, making the bicycle/motorcycle stiffer or lighter, or increasing the stiffness of the steering (of which the rider is the main component) can change the oscillation frequency, though only speed change is applicable in the situation. Many breeds of dogs, but not least German Shepherd, Labrador Retriever, and Border Collie are commonly used as working dogs. If there is insufficient damping in the steering the oscillation will increase until system failure. An assertive dog may consider itself the alpha animal, considering its human master to be subordinate. The restoring force is applied in phase with the progress of the irregularity, and the wheel turns to the other side where the process is repeated. The dog is always aware of its rank relative to other individuals in the group. Some otherwise minor irregularity accelerates the wheel to one side.

Dogs thrive in human society because their relationships with humans mimic their natural social patterns. This shimmy is often seen in shopping cart front wheels. Dog society can be thought of as dog packs characterized by a companionate hierarchy, in which each individual has a rank, and in which there is intense loyalty within the group. While the wobbles can be easily remedied by slowing down, adjusting position, or relaxing one's grip on the handlebars, speed wobbles can be fatal. Dogs thrive in small social groups or packs which, from their viewpoint, can include humans. At higher speeds bicycles can also experience speed wobbles or shimmies, where the front wheel spontaneously oscillates to the left and right. The relationship between dogs and humans is rooted in history and dogs coexist with humans in a variety of ways. [1] [2].

Most dog owners have a large collection of stories about their dogs recognizing individuals by their footsteps outside the door, and so on. Positive trail - found on typical bicycles - creates positive stability by steering the contact patch back under the CG of the bicycle and rider. This ability to read and deliver nonverbal cues makes dogs expert at reading human beings, as well, often even more so than other humans are, who rely on language. Zero trail (as in a unicycle) requires constant rider adjustment. Physiologically, this correlates with such features as a large number of nerves innervating the facial muscles of dogs, allowing subtle control of a wide variety of facial expressions; in contrast to cats, for instance, who have many fewer nerves governing their facial muscles, resulting in a smaller repertoire or "vocabulary" of expressions. Negative trail (rolling a bicycle backwards) results in immediate steering problems. The requirements of coordinating complex social behavior requires that canines have the ability to sense and deliver a wide variety of cues via body language, more so than for even humans, who can use language for the same purpose. The moment due to trail and the weight of the bicycle will turn the front wheel in the direction of the turn.

All dogs have a tremendous capacity to learn complex social behavior and to interpret varied body language and sounds, and, like many predators, can react to and learn from novel situations. One can see the effect that trail has by simply holding a bicycle by the seat and leaning it. Gastric torsion and bloat is a dangerous problem in some large-chested breeds. The greater the amount of trail, the greater the reaction. Dogs are also susceptible to the same ailments that humans are, including diabetes, epilepsy, cancer, and arthritis. This is the distance between the point of contact the front wheel makes with the ground and the place the steering axis makes contact with the ground. Some breeds of dogs are also prone to certain genetic ailments, such as hip dysplasia, luxating patellas, cleft palate, blindness, or deafness. Stability is also influenced by a geometric factor called trail.

Internal parasites include hookworms, tapeworms, roundworms, and heartworms. Jones found he could ride this bike with no difficulty, but did discover that without a rider the non-gyroscopic bike fell over much faster than a regular bike. Common external parasites are various species of fleas, ticks, and mites. By gearing this wheel to the regular front wheel so that it spun in the opposite direction at equal speed, the net angular momentum of both wheels together was close to zero. Diseases commonly associated with dogs include rabies (hydrophobia), canine parvovirus, and canine distemper, and pulmonic stenosis, although there are many others. Jones, whose series of "URBs" ("unrideable bikes" with various modifications to the front end) included a bike which cancelled the gyroscopic effect of the front wheel by dint of attaching a second wheel to his front forks (alongside the regular wheel) whose lower edge was about an inch (25 mm) above the ground. Dogs are susceptible to various diseases, ailments, and poisons, some of which affect humans in the same way, others of which are unique to dogs. H.

It is said that the animals, not just dogs, could sense the tsunami and could therefore flee for life. That gyroscopic effects are unimportant at normal cycling speeds was shown by physicist and researcher into bicycle stability David E. For example, during the tsunami in Southern Asia recently, many animals were seen days before fleeing to the hills. Conversely, a bicycle whose steering fork is locked in a perfectly straight ahead position is virtually impossible to balance. The evolutionary ability of sensing weather can be traced back to when wolves used it to move the pack into proper shelter before a dangerous storm. These forces, perhaps aided at very high speeds by the gyroscopic effect of the spinning wheels,⁴ are sufficiently strong that a riderless bicycle going down a slope will stay upright by itself. This is due to their keen ability to detect fluctuations in barometric pressure and can explain a dog's anxiety before and during a storm. Like the rider's steering adjustments, this motion automatically returns the contact point of the wheel directly under the center of gravity.

Dogs also have the ability to sense inclement weather (mainly thunderstorms) many miles away. Once underway, this effort is largely replaced by physical forces generated by the rotation of the wheels which produce a remarkable "self-steering" effect.³ The angular momentum of the wheels and the torque applied to them by the ground generates a phenomenon called precession, by which the wheel turns, or trails, toward whichever side the bicycle tilts. It has been observed that a lost dog can often find its way home, sometimes traveling over long distances. A rider stays upright on a bicycle by steering the bicycle so that the point where the wheels touch the ground stays underneath the center of gravity. An intensive search for a scent, for instance searching a ship for contraband, can actually be very fatiguing for a dog, and the dog must be motivated to continue this hard work for a long period of time. These changes can impact performance dramatically, cutting minutes off a time trial. In any event, it is established by those who train tracking dogs that it is impossible to teach the dog how to track any better than it does naturally; the object instead is to motivate it properly, and teach it to maintain focus on a single track and ignore any others that might otherwise seem of greater interest to an untrained dog. For this reason more recent designs have concentrated on lowering wind resistance, using aerodynamically shaped tubing, flat spokes on the wheels, and handlebars that allow the rider to bend over into the wind.

The characteristics and behavior of these two types of scent trail would seem, after some thought, to be quite different, the air scent being intermittent but perhaps less obscured by competing scents, whereas the ground scent would be relatively permanent with respect to careful and repetitive search by the dog, but would seem to be much more contaminated with other scents. For instance, lowering a bike's weight by 1 kg, a major effort considering they may weigh less than 15 kg to start with, will have the same effect over a 40 km time trial as removing a protrusion into the air the size of a pencil. What information a dog actually detects when he is scenting is not perfectly understood; although once a matter of debate, it now seems to be well established that dogs can distinguish two different types of scents when trailing, an air scent from some person or thing that has recently passed by, as well as a ground scent that remains detectable for a much longer period. In measured tests these components have almost no effect on cycling performance. Some breeds have been selectively bred for excellence in detecting scents, even compared to their canine brethren. Additionally, advanced wheels are available with low-friction bearings and other features to lower road resistance. Dogs have nearly 220 million smell-sensitive cells over an area about the size of a pocket handkerchief (compared to 5 million over an area the size of a postage stamp for humans). There has been major corporate competition to lower the weight of racing bikes through the use of advanced materials and components.

They can identify a sound's location much faster than a human can, and they can hear sounds up to four times the distance that humans can. This stands as the official record for all human-powered vehicles. Dogs detect sounds as low as the 16 to 20 Hz frequency range (compared to 20 to 70 Hz for humans) and as high as 70,000 to 100,000 Hz (compared to 20,000 Hz for humans)², and in addition have a degree of ear mobility that helps them to rapidly pinpoint the exact location of a sound. The highest speed ever officially attained on the flat, without using motor pacing and wind-blocks, is by Canadian Sam Whittingham, who in 2002 set a 130.36 km/h (81.00 mph) record on his highly aerodynamic recumbent bicycle. Some breeds, particularly the best sighthounds, have a field of vision up to 270° (compared to 100° to 120° for humans), although broad-headed breeds with their eyes set forward have a much narrower field of vision, as low as 180°.^{1, 2}. On a fast racing bicycle, a reasonably fit rider can ride at 50 km/h (30 mph) on flat ground for short periods. Because the lenses of dogs' eyes are flatter than humans', they cannot see as much detail; on the other hand, their eyes are more sensitive to light and motion than humans' eyes. Typical speeds for bicycles are 16 to 32 km/h (10 to 20 mph).

It has also been suggested that dogs see in varieties of purple/violet and yellow shades. Even at moderate speeds, most cycling energy is spent in overcoming aerodynamic drag, which increases with the square of speed; therefore, power needs increase approximately with the cube of speed. Dogs were thought to be dichromats and thus, by human standards, color blind.^{1, 2} New research is now being explored that suggests that dogs may actually see some colour, but not to the extent that humans do. Elite track sprinters are able to attain an instantaneous maximum output of around 2,000 watts, or in excess of 25 watts/kg; elite road cyclists may produce 1,600 to 1,700 watts as an instantaneous maximum in their burst to the finish line at the end of a five-hour long road race. Dogs are predators and scavengers, possessing sharp teeth and strong jaws for attacking, holding, and tearing their food. The average "in-shape" man can produce about 3 watts/kg for more than an hour (e.g., around 200 watts for a 70 kg rider), with top amateurs producing 5 watts/kg and elite athletes achieving 6 watts/kg for similar lengths of time. Within the range of extremes, dogs generally share attributes with their wild ancestors, the wolves. However, because of its efficiency, cycling requires a longer distance, and often greater time, than running to consume the same amount of energy.

Modern dog breeds show more variation in size, appearance, and behavior than any other domestic animal. For many people whose running might be limited by muscle and knee pain, cycling offers comparable outdoor exercise that can be enjoyed by people of a wide range of fitness levels: it is a "no-impact" sport that is easy on the body as long as the bike is properly "fit." In addition, since bicycling can also provide convenient transportation, less self-discipline may be required to keep to the activity, since it has a practical purpose. Many veterinarians recommend that owners neuter/spay their pets around the age of 5 months. Generally used figures are. A female dog can become pregnant on her first heat cycle (which can take place as early as six months), and should be kept away from intact male dogs, including littermates, over the age of 4 months. That same man on a bicycle, on the same ground, with the same power output, can average 25 km/h, so energy expenditure in terms of kcal/kg/km is roughly one-fifth as much. Contrary to myth, it is not required for a female dog to either experience a heat cycle or have puppies before spaying, and likewise, a male dog does not need the experience of mating before neutering; these myths are responsible for numerous unnecessary health problems and unwanted puppies. On firm, flat, ground, a 70 kg man requires about 100 watts to walk at 5 km/h.

The hormonal changes involved are sure to change the animal's personality somewhat, and some object to this angle as the sterilization in itself could be carried out without the excision of organs. In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also a most efficient means of cargo transportation. Spaying and neutering can also help prevent hormone-driven diseases such as breast cancer and prostate cancer, as well as undesired hormone-driven behaviors. In terms of the amount of energy a person must expend to travel a given distance, investigators have calculated it to be the most efficient self-powered means of transportation.¹ From a mechanical viewpoint, up to 99% of the energy delivered by the rider into the pedals is transmitted to the wheels, although the use of gearing mechanisms may reduce this by 10-15% ^{2 9}. It is also common for adult stray dogs who are placed in animal shelters to be euthanized due to lack of space and resources. In both biological and mechanical terms, the bicycle is extraordinarily efficient. Unwanted puppies are abandoned, eaten, or sometimes disposed of in an inhumane fashion. Others maintain their own bicycles, enhancing their enjoyment of the hobby of cycling.

Dog experts advise that dogs not intended for further breeding should be spayed or neutered so that they do not have undesired puppies. Some bicycle parts, particularly hub-based gearing systems, are complex, and many prefer to leave maintenance and repairs to professionals. Spaying or neutering refers to the removal of the male testicles or the female ovaries and uterus, in order to remove the capability to procreate, and to kill the libido. More specialised parts now require more complex tools, including proprietary tools specific for a given manufacturer. For example, the Bulldog often requires artificial insemination and almost always requires cesarean section for giving birth. A single tool once sufficed for most repairs. Some breeds have been developed to emphasize certain physical traits beyond the point at which they can safely bear litters on their own. Many cyclists carry tool kits, containing at least a tire patch kit, tire levers, and spanners.

Since a mother can only provide nutrients and care to a limited number of offspring, humans must assist in the care and feeding when the litter exceeds approximately eight puppies. No correlation between decreased injury rates and helmet use has been demonstrated in whole populations. An average litter consists of about six puppies, though this number may vary widely based on the breed of dog. Outside the West, use of helmets by utility cyclists is practically unknown. Dogs bear their litters roughly 9 weeks after fertilization. In Australia and New Zealand, and parts of Canada, helmets are required by law. This rule is altered in domesticated animals since larger litters are often favoured for economic reasons. federal law requires helmets, many states require children to wear them, and some municipalities require them for all riders.

A general rule of thumb is that a mammal will produce half as many offspring as the number of teats on the mother. While no U.S. The different rates of maturation are responsible for the menarche, not the chronological age. In North America a significant minority, possibly up to 25% of bicyclists, wear helmets. Like most mammals, the age that a bitch first comes into season is mostly a function of her current body weight as a proportion of her body weight when fully mature. In most countries where cycling is common, bicycle helmet use is negligible. Most bitches come into season for the first time between 6 and 12 months, although some larger breeds delay until as late as 2 years. Toe-clips help to keep the foot planted firmly on the pedals, and enable the cyclist to pull as well as push the pedals.

Conversely, undomesticated canine species experience estrus once a year, typically in late winter. Technical accessories include solid-state speedometers and odometers for measuring distance. This is also called in season or in heat. Other accessories include lights, pump, lock, and additional (pedal or wheel-mounted) reflectors. The amount of time between cycles varies greatly among different dogs, but a particular dog's cycle tends to be consistent through her life. Parents sometimes add rear-mounted child seats and/or an auxiliary saddle fitted to the crossbar to transport children. The ability of female domestic dog to come into estrus at any time of the year and usually twice a year is also valued. Rear racks or carriers can be used to carry items such as school satchels.

In domestic dogs, one of the behaviours that is noted is the abolition of the pair bond seen in wild canines. Front-mounted wicker or steel baskets for carrying goods are often used. As with most domesticated species, one of the first and strongest effects seen from selective breeding is selection for cooperation with the breeding process as directed by humans. Kick stands help with parking. Dog owners may accidentally allow their pets to breed without regard to bloodlines. Chainguards and mudguards, or fenders, protect clothes and moving parts from oil and spray. Dog breeders also have accurate information on the complexities of the reproductive process for the breed of dog that they are accustomed to handling. Utility bicycles have many standard features which enhance their usefulness and comfort that would be considered accessories on sports bicycles.

Dog breeders have access to records which allow them to accurately guess which characteristics will "breed true" in a particular dog. For these reasons, one must weigh the advantages and disadvantages of using a hydraulic system versus a mechanical system. Breeders who do this are usually experienced in this process. This is due to the brake losing its ability to transmit force through incompressible fluids, since some of it has become a gas, which is compressible. Sometimes dogs are bred to create puppies to sell, or sometimes to carry on an award-winning purebred line. Also, the hydraulic fluid may boil on steep, continuous downhills. Among professional breeders, dogs are only allowed to mate for a specific purpose. However, since hydraulic disc brakes usually require relatively specialized tools to bleed the brake systems, repairs on the trail are difficult to perform, whereas mechanical disc brakes rarely fail.

Dogs also may find some poisons attractive, including antifreeze and snail bait. Hydraulic disc brake systems generally keep contaminants out better. Alcoholic beverages pose much the same temptation and hazard to dogs as to humans. Mechanical disc brakes have less modulation than hydraulic disc brake systems, and since the cable is usually open to the outside, mechanical disc brakes tend to pick up small bits of dirt and grit in the cable lines when ridden in harsh terrain. Some human medications, such as acetaminophen/paracetamol (Tylenol), are highly toxic to dogs. Two main disc brake systems exist: hydraulic and mechanical (cable-actuated). Some foods commonly enjoyed by humans are dangerous to dogs, including chocolate (Theobromine poisoning), onions, grapes and raisins, Macadamia nuts, and hops. The use of tires as large as 3.0 inches in width also makes disc brakes a necessity, as rim brakes simply cannot straddle a tire that wide.

For a discussion on one use of treats in training, see clicker training. The advantages of discs make them well-suited to steep, extended downhills through wet and muddy off-road terrain, which falls under the category of downhill and freeride bicycle riding. Such dogs might consider anything dropped by humans, including small but indigestible objects (such as marbles, coins, rings, etc.), to be treats as well, which could be dangerous to the dogs when ingested. In the late 1990s, disc brakes appeared on some off-road bicycles, tandems and recumbent bicycles, but are considered impractical on road bicycles, which rarely encounter conditions where the advantages of discs are significant. Many dogs consider anything given to them directly by hand to be a treat, even the food they are accustomed to at meal time. With hand-operated brakes, force is applied to brake handles mounted on the handle bars and then transmitted via Bowden cables to the friction pads. Eating grass might make the dog vomit, so one explanation is that dogs eat grass to remove unwanted content from their stomachs. Hub drum brakes do not cope well with extended braking, so rim brakes are favoured in hilly terrain.

Explanations abound, but rationales such as that it neutralizes acid are just guesses. A rear hub brake may be either hand-operated or pedal-actuated, as in the back pedal coaster brakes which were the rule in North America until the 1960s. Dogs sometimes eat grass, a harmless activity. Bicycle brakes are either rim brakes, in which friction pads are compressed against the wheel rims, internal hub brakes, in which the friction pads are contained within the wheel hubs, or disc brakes. This research is also true of other mammals. The reclined, low seating position does provide increased aerodynamics over standard seating. It has also been noted that extremely stressful conditions, such as the Iditarod race and scientific studies of similar conditions, suggest that high-protein diets including meat help prevent damage to muscle tissue. Recumbent bicycles have more chair-like seats, and so are much more comfortable to ride, although generally slower up hills due to this positioning.

In the wild these diets are typically pursued in the absence of available meat. For racing bikes where the rider is bent over, weight is more evenly distributed between the handlebars and saddle, and the hips are flexed, and a narrower and harder saddle is more efficient. Some sources suggest that a dog fed on a stict vegetarian diet may develop dilated cardiomyopathy since it lacks L-carnitine.^[3]. With comfort bikes and hybrids the cyclist sits high over the seat, their weight directed down onto the saddle, such that a wider and more cushioned saddle is preferable. Domestic dogs can survive healthily on a reasonable and carefully designed vegetarian diet, particularly if eggs and milk products are included. Comfort depends on riding position. Wild canines not only eat available plants to obtain key amino acids, but may also obtain nutrients from vegetable matter from the stomach contents of their herbivorous prey. Seats, or saddles, also vary with rider preference, from the cushioned ones favoured by short-distance riders to narrower seats which allow more free leg swings.

Dogs are able to healthily digest a variety of foods including vegetables and grains, and in fact can consume a large proportion of these in their diet. The Bullhhorn was banned from ordinary road racing because it is considered there is less fine control in bike traffic. Unlike an obligate carnivore, such as a cat, a dog is not dependent on meat protein in order to fulfill its dietary requirements. These are usually used in conjunction with the aero bar, a pair of forward-facing extensions spaced close together, to promote better aerodynamics. The classification in the Order Carnivora does not necessarily mean that a dog's diet must be restricted to meat. Bullhorn style handlebars are often seen on modern time trial bicycles, equipped with two forward-facing extensions, allowing a rider to rest his entire forearm on the bar. Presently, there is academic discussion as to whether domestic dogs are omnivores or carnivores. Variations on these styles exist.

For a detailed discussion on what dog intelligence is, see dog intelligence. Mountain bikes feature a crosswise handlebar, which helps prevent the rider from pitching over the front in case of sudden deceleration. Anecdotal evidence suggests that dogs have a reasonably high intelligence. Racing handlebars are "dropped", offering the cyclist either an aerodynamic "hunched" position or a more upright posture in which the hands grip the brake lever mounts. Among dog lovers, dogs are generally valued for their intelligence. Touring handlebars, the norm in Europe and elsewhere until the 1970s, curve gently back toward the rider, offering a natural grip and comfortable upright position. They have small, tight feet, and walk on their toes. Three styles of handlebar are common.

Its skeleton provides the ability to run and leap. The handlebars rotate the fork and the front wheel via the stem, which articulates with the headset. Like most other predatory mammals, the dog has powerful muscles, a cardiovascular system that supports both sprinting and endurance, and teeth for catching, holding, and tearing. Retro-Direct drivetrains used on some early 20th century bicycles have been resurrected by bicycle hobbyists. Although selective breeding has changed the appearance of many breeds, all dogs retain the basic ingredients from their distant ancestors. This also results in increased wear because of the lateral deflection of the chain. Many additional terms are used for dogs that are not purebred; see Terms for mixed-breed dogs. Derailleur efficiency is also compromised with cross-chaining, or running large-ring to large-cog or small-ring to small-cog.

The word is sometimes used to refer collectively to any mammal belonging to the family Canidae (as in "the dog family"), such as wolves, foxes and coyotes. Efficiency generally decreases with smaller cog sizes because the chain must bend more sharply as it rolls on and off the cog, and it also forms a sharp angle at the chain tensioner⁹. Dog, in common usage, refers to the domestic pet dog, Canis lupus familiaris (originally classified as Canis familiaris by Linnaeus in 1758, but reclassified as a subspecies of the wolf, Canis lupus, by the Smithsonian Institution and the American Society of Mammalogists in 1993). In derailleur mechanisms the highest efficiency is achieved by the larger cogs. . Derailleur type mechanisms fare better, with a typical mid-range product (of the sort used by serious amateurs) achieving between 88% and 99% efficiency at 100W. In other cultures, some dogs are used as food. Which ratios are best and worst depends on the specific model of hub gear.

Dogs have lived with and worked with humans in so many roles that their loyalty has earned them the sobriquet "man's best friend." Conversely, some cultures consider dogs to be unclean. In a typical hub gear mechanism the mechanical efficiency will be between 82% and 92% depending on the ratio selected. In many countries, the most common and perhaps most important role of dogs is as companions. The efficiency varies considerably with the gear ratio being used. For dogs that do not have traditional jobs, a wide range of dog sports provide the opportunity to exhibit their natural skills. While generally variable ratio gear mechanisms are essential for human efficiency, they do reduce mechanical efficiency. Dogs fill a variety of roles in human society and are often trained as working dogs. Fixed-gear track racing bikes have transmission efficiencies of over 99% (nearly all the energy put in at the pedals ends up at the wheel).

Dogs, like humans, are highly social animals and pack hunters; this similarity in their overall behavioral pattern accounts for their trainability, playfulness, and ability to fit into human households and social situations. Mountain bikes and most entry-level road racing bikes may offer an extremely low gear to facilitate climbing slowly on steep hills. For example, heights at the withers range from just a few inches (such as the Chihuahua) to roughly three feet (such as the Irish Wolfhound), and colors range from white to black, with reds, grays (usually called blue), and browns occurring in a tremendous variation of patterns. Road bicycles have close set multi-step gearing, which allows very fine control of cadence, while utility cycles offer fewer, more widely spaced speeds. In this time, the dog has developed into hundreds of breeds with a great degree of variation. Internal hub gearing still predominates in some regions, particularly on utility bikes, whereas in other regions, such as the USA, external derailleur systems predominate. Dogs were first domesticated from wolves at least 15000 years ago[1] but perhaps as long as 150,000 years ago based on recent genetic fossil evidence and DNA evidence^[2]. However, they may be heavier and/or more expensive, and often do not offer the same range or number of gears.

The dog is a canine mammal of the Order Carnivora. Internal hub gears are much less affected by adverse weather conditions than derailleurs, and often last longer and require less maintenance. It too has the body plan of an adult canine predator. The gear systems are hand-operated, via cables (or rarely, hydraulics), and are of two types. The least paedomorphic behavior pattern may be that of the basenji, bred in Africa to hunt alongside humans almost on a peer basis; this breed is often described as highly independent, neither needing nor appreciating a great deal of human attention or nurturing, often described as "catlike" in its behavior. Since cyclists' legs produce a limited amount of power most efficiently over a narrow range of cadences, a variable gear ratio is needed to maintain an optimum pedaling speed while covering varied terrain. Terriers similarly have adult aggressive behavior, famously coupled with a lack of juvenile submission, and display correspondingly adult physical features such as erect ears, although many breeds have also been selected for size and sometimes dwarfed legs to enable them to pursue prey in their burrows. Between the chain and rear wheel may be interspersed various gearing systems, described below, which vary the number of rear wheel revolutions produced by each turn of the pedals.

This contrasts with sighthounds, who pursue and attack perceived prey on sight, and who maintain the mature canine body type with erect ears, lean bodies, and adult coats. Attached to the crank is the chainring which drives the chain, which in turn rotates the rear wheel via the rear sprockets. Scenthounds maintain an intermediate body type and behavior pattern that causes them to actually pursue prey by tracking their scent, but tend to refrain from actual individual attacks in favor of vocally summoning the pack leaders (in this case, humans) to do the job. The drivetrain begins with pedals which rotate the crankset, which fit into the bottom bracket. Their physical characteristics are closer to that of the mature wild canine than the sheepdog breeds, but they typically do not have erect ears, etc. More expensive carbon fibre and titanium frames are now also available, as well as advanced steel alloys. Similarly, they seize dead or wounded prey and bring it back to the "pack", even though they did not attack it themselves, that is, "retrieving" behavior. In the 1980s aluminium alloy frames became popular, and their affordability now makes them common.

They identify potential prey and freeze into immobility, for instance, but refrain from then stalking the prey as an adult predator would do next; this results in the "pointing" behavior for which such dogs are bred. Celluloid found application in mudguards, and aluminium alloys are increasingly used in components such as handlebars, seat stems (also known as seatposts), and brake levers. Gun dog breeds used in hunting—that is, pointers, setters, spaniels, and retrievers—have an intermediate degree of paedomorphism; they are at the point where they share in the pack's hunting behavior, but are still in a junior role, not participating in the actual attack. Since the late 1930s alloy steels have been used for frame and fork tubes in higher quality machines. (Compare to the physical appearance of the border collie, a sheep herding dog, whose physical configuration is closer to that of an adult wild canine and who therefore has a greater capacity to frighten sheep into a desired pattern of movement, along with the more adult aggressive temperament to do so). Historically, materials used in bicycles have followed a similar pattern as in aircraft, the goal being strength and low weight. In addition, they retain very juvenile physical characteristics such as round bodies and heads, soft coats, ears that hang down, and so on, which do not elicit fear responses from the sheep in the way that an appearance similar to that of an adult wolf would. Although some women's bicycles continue to use this frame style, there is also a hybrid form, the mixte or step-through frame, which also allows easier mounting and dismounting for both male and female riders.

Livestock guardian dogs retain the most juvenile characteristics: they stay close to home with their foster "litter" (which might include a flock of sheep), rather than going out hunting, they have almost no predatory behavior (which would be disastrous in the vicinity of such a natural prey stimulus as sheep), they respond to perceived threats with a lot of vocalization and attempts to alert and engage the dominant individuals in their "pack" (i.e. humans) whenever possible, engaging in actual combat only as a last resort. This allowed the rider to dismount while wearing a skirt or dress. Canine in common usage is a synonym for dog or an adjective meaning dog; for example, in the common expression "canine companion". Historically, women's bicycle frames had a top tube that connected in the middle of the seat tube instead of the top, resulting in a lower standover height. Pooch, Poochie, Pup, Puppy, Doggy, Doggie are all informal and affectionate terms for a dog often used by children. The seat stays connect the top of the seat tube (often at or near the same point as the top tube) to the rear dropouts. Puppy is a juvenile dog. The chain stays run parallel to the chain, connecting the bottom bracket to the rear dropouts.

Pack is used to denote a group of dogs. The rear triangle consists of the seat tube and paired chain stays and seat stays. Bitch is a female dog. The top tube connects the head tube to the seat tube at the top, and the down tube connects the head tube to the bottom bracket. Dog is also a term used by breeders to specifically denote a male domestic dog. The head tube contains the headset, the interface with the fork. The front triangle consists of the head tube, top tube, down tube and seat tube.

Nearly all modern upright bicycles feature the diamond frame, composed of two triangles: the front triangle and the rear triangle. Since a moving bicycle makes very little noise, in many countries bicycles must have a warning bell for use when approaching pedestrians, equestrians and other bicyclists. As some generator or dynamo-driven lamps only operate while moving, rear reflectors are frequently also mandatory. In some places, bicycles must have functioning front and rear lights or lamps.

In many jurisdictions it is an offence to use a bicycle that is not in roadworthy condition and which does not have functioning front and rear brakes. The traffic codes of many countries reflect these definitions and demand that a bicycle satisfy certain legal requirements, including licencing, before it can be used on public roads. The 1968 Vienna Convention on Road Traffic considers a bicycle to be a vehicle, and a person controlling a bicycle is considered a driver. Manufacturers responded with the hybrid bicycle, which restored many of the features long enjoyed by riders of the time-tested European utility bikes.

These task-specific designs led many American recreational cyclists to demand a more comfortable and practical product. In the late 1980s the mountain bike became particularly popular, and in the 1990s something of a major fad. By the 1980s these newer designs had driven the three-speed bicycle from the roads. While 10-speeds were the rage in the 1970s, 12-speed designs were introduced in the 1980s, and today most bikes feature 18 or more speeds.

Sales were also helped by a number of technical innovations that were new to the US market, including higher performance steel alloys and gearsets with an increasing number of gears. Bicycle sales in the United States boomed, largely in the form of the racing bicycles long used in such events as the hugely popular Tour de France. In North America, increasing consciousness of physical fitness and environmental preservation spawned a renaissance of bicycling in the late 1960s. Especially in Amsterdam they are often colourfully painted and/or otherwise decorated.

In the Netherlands, such so-called 'granny bikes' have remained popular, and are again in production. In other parts of the world however, such as China, India, and European countries such as Germany, Denmark, and the Netherlands, the traditional utility bicycle remained a mainstay of transportation, its design only gradually changing to incorporate hand-operated brakes and internal hub gears allowing up to seven speeds. In North America, bicycle sales declined markedly after 1905, to the point where by the 1940s, they had largely been relegated to the role of children's toys. In many western countries the use of bicycles levelled off or declined, as motorized transportation became affordable and car-centred policies led to an increasingly hostile road environment for bicycles.

By the mid-20th century bicycles had become the primary means of transportation for millions of people around the globe. Facilitated by connections between European nations and their overseas colonies, European-style bicycles were soon available worldwide. Schwinn bicycles soon featured widened tires and spring-cushioned, padded seats, sacrificing some efficiency for increased comfort. Schwinn emigrated to the United States, where he founded his similarly successful company in Chicago in 1895.

Bowden started the Raleigh company in Nottingham in the 1890s, and soon was producing some 30,000 bicycles a year. Successful early bicycle manufacturers included Englishman Frank Bowden and German builder Ignaz Schwinn. By the turn of the century, bicycling clubs flourished on both sides of the Atlantic, and touring and racing were soon the rage. Derailleur gears and hand-operated, cable-pull brakes were also developed during these years, but were only slowly adopted by casual riders.

This refinement led to the 1898 invention of coaster brakes. Shortly thereafter the rear freewheel was developed, enabling the rider to coast without the pedals spinning out of control. In 1888 Scotsman John Boyd Dunlop introduced the pneumatic tire, which soon became universal. The next innovations increased comfort and ushered in the 1890s Golden Age of Bicycles.

While the Starley design was much safer, the return to smaller wheels made for a bumpy ride. Soon the seat tube was added, creating the double-triangle, diamond frame of the modern bike. Starley's 1885 Rover is usually described as the first recognizably modern bicycle. These models were known as dwarf safeties, or safety bicycles, for their lower seat height and better weight distribution.

Lawson, and Shergold solved this problem by introducing the chain and producing rear-wheel drive. H. Starley, J. K.

Starley's nephew, J. Having to both pedal and steer via the front wheel remained a problem. The subsequent dwarf ordinary addressed some of these faults, by adding gearing, reducing the front wheel diameter, and setting the seat further back with no loss of speed. The primitive bicycles of this generation were difficult to ride, and the high seat and poor weight distribution made for dangerous falls.

British cyclists likened the disparity in size of the two wheels to their coinage, nicknaming it the penny-farthing. With tires of solid rubber, his machine became known as the ordinary. He mounted the seat more squarely over the pedals, so that the rider could push more firmly, and further enlarged the front wheel to increase the potential for speed. The Boneshaker was further refined by James Starley in the 1870s.

Lallement emigrated to America, where he recorded a patent on his bicycle in 1866 in New Haven, Connecticut. Their creation, which came to be called the "Boneshaker", featured a heavy steel frame on which they mounted wooden wheels with iron tires. In the 1850s and 1860s, Frenchman Ernest Michaux and his pupil Pierre Lallement took bicycle design in a different direction, placing pedals on an enlarged front wheel. However, some reports describe MacMillan's vehicle as more of a "quadricycle".

Scottish blacksmith Kirkpatrick MacMillan shares creative credit with von Drais for adding a treadle drive mechanism, in 1840, that enabled the rider to lift his feet off the ground while driving the rear wheel. These were pushbikes, powered by the action of the rider's feet pushing against the ground. He patented his draisine, a number of which still exist, including one at the Paleis het Loo museum in Apeldoorn, the Netherlands. The most likely originator of the bicycle is German Baron Karl von Drais, who rode his 1817 machine while collecting taxes from his tenants.

Most bicycle historians now believe that these hobby-horses with no steering mechanism probably never existed, but were made up by Louis Baudry de Saunier, a 19th-century French bicycle historian. One of these, the scooter-like dandy horse of the French Comte de Sivrac, dating to 1790, was long cited as the earliest bicycle. Its earliest known forebears were called velocipedes, and included many types of human-powered vehicles. No single time or person can be identified with the invention of the bicycle.

. A recurrent theme in bicycling has been the tension between bicyclists and drivers of motor vehicles, each group arguing for its fair share of the world's roadways. Beyond recreation and transportation, bicycles have been adapted for use in many occupations, including the military, local policing, courier services, and sports. In its early years, bicycle construction drew on pre-existing technologies; more recently, bicycle technology has contributed, in turn, to other, newer areas.

The bicycle has affected history considerably in both the cultural and industrial realms. A bicycle in which the rider lies in a prone position and which may be covered in an aerodynamic fairing to achieve very low air drag is referred to as a Recumbent_bicycle or Human Powered Vehicle. Air drag, which increases with the square of speed, requires increasingly higher power outputs relative to speed. A human being travelling on a bicycle at low to medium speeds of around 10-15 mph (16-24 kph), using only the energy required to walk, is the most energy-efficient means of transport generally available.

as a Child's toy, in adult recreation and fitness, as a means of everyday transport, in cyclo-touring, as a basis of cycle sport (branches: track, off-road or MTB, downhill, cyclo-cross, time trialling, road racing, cycle speedway, cycle polo, BMX), and as a basis for static gymnasium or home fitness versions. A remarkable aspect of the bicycle is its widespread adoption in many different fields of human activity, e.g. The basic shape and configuration of the frame, wheels, pedals, saddle and handlebars has hardly changed since the first chain-driven model was developed around 1885, although many important detail improvements have been made since, especially in recent years using modern materials and computer-aided design. The bicycle is one of the most notable of human inventions.

To distinguish a bicycle from a motorcycle, it is also called a push-bike. Numbering over 1,000,000,000 in the world today, bicycles provide the principal means of transportation in many regions and a popular form of recreational transport in others. First introduced in 19th-century Europe, bicycles evolved quickly into their familiar, current design. A bicycle, or bike, is a pedal-driven land vehicle with two wheels attached to a frame, one behind the other.

ISO 4210 Cycles — Safety requirements for bicycles. ISO 8090 Cycles — Terminology (same as BS 6102-4). ISO 5775 Bicycle tire and rim designations. A unicycle is not a bicycle, as it has only one wheel, but it is related.

Art bikes: Some bikes are built so that the frame appears to be made of junk or found objects: Bongo the Clown built several ridable parade bikes which were as much kinetic sculptures as transport. Come-apart bike, (essentially a unicycle, plus a set of handlebars attached to forks and a wheel). tall bike (often called an upside down bike, constructed so that the pedals, seat and handlebars are all higher than normal) -- other types tall bikes are made by welding two more more bicycle frames on top of each other, and running additional chains from the pedals to the rear wheel. bucking bike (with one or more eccentric wheels).

Some types of clown bicycles are: