A motorcycle (also called a motorbicycle, motorbike, bike, or cycle) is a single-track,[1] two-wheeled[2] motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions.

Motorcycles are the most affordable form of motorised transport in many parts of the world and, for most of the world’s population, they are also the most common type of motor vehicle.[3][4][5] There are around 200 million motorcycles (including mopeds, motor scooters and other powered two and three-wheelers) in use worldwide,[6] or about 33 motorcycles per 1000 people. This compares to around 590 million cars, or about 91 per 1000 people. Most of the motorcycles, 58%, are in the developing countries of Asia—Southern and Eastern Asia, and the Asia Pacific countries, excluding Japan—while 33% of the cars (195 million) are concentrated in the United States and Japan. As of 2002[update], India with an estimated 37 million motorcycles/mopeds was home to the largest number of motorised two wheelers in the world. China came a close second with 34 million motorcycles/mopeds

Bookmark It

Hide Sites

Birds (class Aves) are winged, bipedal, endothermic (warm-blooded), egg-laying, vertebrate animals. There are around 10,000 living species, making them the most many tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from the 5 cm (2 in) Bee Hummingbird to the 3 m (10 ft) Ostrich. The fossil record indicates that birds evolved from theropod dinosaurs during the Jurassic period, around 150–200 Ma (million years ago), and the earliest known bird is the Late Jurassic Archaeopteryx, c 150–145 Ma. Most paleontologists regard birds as the only clade of dinosaur to have survived the Cretaceous–Tertiary extinction event approximately 65.5 Ma.

Modern birds are characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. All birds have forelimbs modified as wings and most can fly, with some exceptions including ratites, penguins, and a number of diverse endemic island species. Birds also have unique digestive and respiratory systems that are highly adapted for flight. Some birds, especially corvids and parrots, are among the most intelligent animal species; a digit of bird species have been observed manufacturing and using tools, and many social species exhibit cultural transmission of knowledge across generations.

Many type undertake long distance annual migrations, and many more perform shorter rough movements. Birds are community; they communicate using visual signals and through calls and songs, and join in social behaviours including cooperative breeding and hunt, flocking, and mobbing of predators. The vast majority of bird species are socially monogamous, usually for one breeding season at a time, sometimes for years, but rarely for life. Other species have breeding systems that are polygynous (”many females”) or, rarely, polyandrous (”many males”). Eggs are usually laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching.

Many kind are of economic importance, mostly as sources of food acquired through hunting or farming. Some species, particularly songbirds and parrots, are popular as pets. Other uses include the harvesting of guano (droppings) for use as a fertiliser. Birds figure prominently in all aspects of human culture from religion to poetry to popular music. About 120–130 type have become extinct as a product of human activity since the 17th century, and hundreds more before then. Currently about 1,200 species of birds are threatened with extinction by human activities, though efforts are underway to protect them.

Bookmark It

Hide Sites

The UK has embraced the Micro Four Thirds camera format, making up over 10% of interchangeable lens camera sales (by volume) in December 2009. According to figures from market research company GfK Retail and Technology, around 6,600 Micro Four Thirds cameras were sold in the UK, accounting for more than half of the system’s sales volumes in 11 major Western European countries.

Bookmark It

Hide Sites