Is Skateboard Still Evolving?

Son Guthrie

نتاج البحث: مساهمة أخرى

ملخص

A skateboard is a type of sports equipment used for skateboarding. They are usually made of a specially designed 7-8 ply maple plywood deck and polyurethane wheels attached to the underside by a pair of skateboarding trucks. The skateboarder moves by pushing with one foot while the other foot remains balanced on the board, or by pumping one's legs in structures such as a bowl or half pipe. A skateboard can also be used by simply standing on the deck while on a downward slope and allowing gravity to propel the board and rider. If the rider's leading foot is their right foot, they are said to ride "goofy;" if the rider's leading foot is their left foot, they are said to ride "regular." If the rider is normally regular but chooses to ride goofy (or vice versa), they are said to be riding in "switch". A skater is typically more comfortable pushing with their back foot; choosing to push with the front foot is commonly referred to as riding "mongo", and has negative connotations of style and effectiveness in the skateboarding community. Since the early 2000s electric skateboards have appeared. These no longer require the propelling of the skateboard by means of the feet; rather an electric motor propels the board, fed by an electric battery. There is no governing body that declares any regulations on what constitutes a skateboard or the parts from which it is assembled. Historically, the skateboard has conformed both to contemporary trends and to the ever-evolving array of stunts performed by riders/users, who require a certain functionality from the board. The board shape depends largely upon its desired function. Longboards are a type of skateboard with longer wheelbase and larger, softer wheels. The two main types of skateboards are the longboard and the shortboard. The shape of the board is also important: the skateboard must be concaved to perform tricks. Longboards are usually faster and are mostly used for cruising and racing, while shortboards are mostly used for doing tricks and riding in skateparks.Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction. Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources of genetic variation. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or rare within a population. The circumstances that determine whether a characteristic should be common or rare within a population constantly change, resulting in the change in heritable characteristics arising over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms and molecules.The scientific theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the mid-19th century and was set out in detail in Darwin's book On the Origin of Species. Evolution by natural selection was first demonstrated by the observation that more offspring are often produced than can possibly survive. This is followed by three observable facts about living organisms: (1) traits vary among individuals with respect to their morphology, physiology and behaviour (phenotypic variation), (2) different traits confer different rates of survival and reproduction (differential fitness) and (3) traits can be passed from generation to generation (heritability of fitness). Thus, in successive generations members of a population are more likely to be replaced by the progenies of parents with favourable characteristics that have enabled them to survive and reproduce in their respective environments. In the early 20th century, other competing ideas of evolution such as mutationism and orthogenesis were refuted as the modern synthesis reconciled Darwinian evolution with classical genetics, which established adaptive evolution as being caused by natural selection acting on Mendelian genetic variation.All life on Earth shares a last universal common ancestor (LUCA) that lived approximately 3.5–3.8 billion years ago. The fossil record includes a progression from early biogenic graphite, to microbial mat fossils, to fossilised multicellular organisms. Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis) and loss of species (extinction) throughout the evolutionary history of life on Earth. Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct phylogenetic trees.Evolutionary biologists have continued to study various aspects of evolution by forming and testing hypotheses as well as constructing theories based on evidence from the field or laboratory and on data generated by the methods of mathematical and theoretical biology. Their discoveries have influenced not just the development of biology but numerous other scientific and industrial fields, including agriculture, medicine and computer science.
اللغة الأصلية???core.languages.en_GB???
المعرِّفات الرقمية للأشياء
حالة النشر???researchoutput.status.published??? - 2019

سلسلة المنشورات

الاسمoracle.com

بصمة

أدرس بدقة موضوعات البحث “Is Skateboard Still Evolving?'. فهما يشكلان معًا بصمة فريدة.
  • Why Do People Use Se Work?

    Guthrie, S. (???impact.roles.impact.participant???)

    التأثير: ???impact.impacttypes.impact.impact???

قم بذكر هذا