occupation robert bakewell 
Ovis is a genus of mammals , part of the goat - antelope subfamily of the ruminant family Bovidae . Its five or more highly sociable species are known as sheep . The domestic sheep is one ___MASK58___ of the genus , and is thought to be descended from the wild mouflon of central and southwest Asia . Fiber or fibre ( from the Latin fibra ) is a natural or synthetic substance that is significantly longer than it is wide . Fibers are often used in the manufacture of other materials . The strongest ___MASK73___ materials often incorporate fibers , for example carbon fiber and ultra - high - molecular - weight polyethylene . Agriculture is the cultivation and breeding of animals , plants and fungi for food , fiber , biofuel , medicinal plants and other products used to sustain and enhance human life . Agriculture was the key development in the rise of sedentary human civilization , whereby farming of domesticated species created food surpluses that nurtured the development of civilization . The study of agriculture is known as agricultural ___MASK39___ . The history of agriculture dates back thousands of years , and its development has been driven and defined by greatly different climates , cultures , and technologies . Industrial agriculture based on large - scale monoculture farming has become the dominant agricultural methodology . Biology is a natural ___MASK39___ concerned with the study of life and living organisms , including their structure , function , growth , evolution , distribution , identification and taxonomy . Modern biology is a vast and eclectic field , composed of many branches and subdisciplines . However , despite the broad scope of biology , there are certain ___MASK65___ and unifying concepts within it that govern all study and ___MASK1___ , consolidating it into single , coherent field . In ___MASK65___ , biology recognizes the cell as the basic unit of life , genes as the basic unit of heredity , and evolution as the engine that propels the synthesis and creation of new species . It is also understood today that all the organisms survive by consuming and transforming energy and by regulating their internal environment to maintain a stable and vital condition known as homeostasis . Chemistry is a branch of physical ___MASK39___ that studies the composition , structure , properties and change of matter . Chemistry includes topics such as the properties of individual atoms , how atoms form chemical bonds to create chemical compounds , the interactions of substances through intermolecular forces that give matter its ___MASK65___ properties , and the interactions between substances through chemical reactions to form different substances . In ___MASK72___ , energy is the property that must be transferred to an object in order to perform work on  or to heat  the object , and can be converted in form , but not created or destroyed . The SI unit of energy is the joule , which is the energy transferred to an object by the mechanical work of moving it a distance of 1 metre against a force of 1 newton . Economics (, ) is a social ___MASK39___ concerned with the factors that determine the production , distribution , and consumption of goods and services . The term " economics " comes from the Ancient Greek from (', pronounced " eekos ", " house ") and (', " custom " or " law "), hence " rules of the house ( hold for good management )". ' Political economy ' was the earlier name for the subject , but economists in the late 19th century suggested " economics " as a shorter term for " economic ___MASK39___ " to establish itself as a separate discipline outside of political ___MASK39___ and other social sciences . A ___MASK18___ - gatherer is a human living in a society in which most or all food is obtained by foraging ( collecting wild plants and pursuing wild animals ), in contrast to agricultural societies , which rely mainly on domesticated species . Ruminants are mammals that are able to acquire nutrients from plant - based food by fermenting it in a specialized stomach ___MASK62___ to digestion , principally through microbial actions . The process typically requires the fermented ingesta ( known as cud ) to be regurgitated and chewed again . The process of rechewing the cud to further break down plant matter and stimulate digestion is called rumination . The word " ruminant " comes from the Latin " ruminare ", which means " to chew over again ". Ecology ( from , " house ", or " environment "; -  , " study of ") is the scientific analysis and study of interactions among organisms and their environment . It is an interdisciplinary field that includes biology , geography , and Earth ___MASK39___ . Ecology includes the study of interactions organisms have with each other , other organisms , and with abiotic components of their environment . Topics of interest to ecologists include the ___MASK17___ , distribution , amount ( biomass ), and number ( population ) of particular organisms , as well as cooperation and competition between organisms , both within and among ecosystems . Ecosystems are composed of dynamically interacting parts including organisms , the communities they make up , and the non - living components of their environment . Ecosystem processes , such as primary production , pedogenesis , nutrient cycling , and various niche construction activities , regulate the flux of energy and matter through an environment . These processes are sustained by organisms with specific life history traits , and the variety of organisms is called biodiversity . Biodiversity , which refers to the varieties of species , genes , and ecosystems , enhances certain ecosystem services . Plant ___MASK47___ is a subdiscipline of botany concerned with the functioning , or ___MASK47___ , of plants . Closely related fields include plant morphology ( structure of plants ), plant ecology ( interactions with the environment ), phytochemistry ( biochemistry of plants ), cell biology , genetics , biophysics and molecular biology . The sheep (" Ovis aries ") is a quadrupedal , ruminant mammal typically kept as livestock . Like all ruminants , sheep are members of the order Artiodactyla , the even - toed ungulates . Although the name " sheep " applies to many species in the genus " Ovis ", in everyday usage it almost always refers to " Ovis aries ". Numbering a little over one billion , domestic sheep are also the most numerous species of sheep . An adult female sheep is referred to as a " ewe ", an intact male as a " ram " or occasionally a " tup ", a castrated male as a " wether ", and a younger sheep as a " lamb ". Livestock are domesticated animals raised in an agricultural setting to produce commodities such as food , fiber , and labor . The term is often used to refer solely to those raised for food , and sometimes only farmed ruminants , such as cattle and goats . In recent years , some organizations have also raised livestock to promote the survival of rare breeds . The breeding , maintenance , and slaughter of these animals , known as animal husbandry , is a component of modern agriculture that has been practiced in many cultures since humanity ' s transition to farming from ___MASK18___ - gatherer lifestyles . Plant genetics is a very broad term . There are many facets of genetics in ___MASK65___ , and of course there are many facets to plants . The definition of genetics is the branch of biology that deals with heredity , especially the mechanisms of hereditary transmission and the variation of inherited characteristics among similar or related organisms . And the definition of a plant is any of various photosynthetic , eukaryotic , multicellular organisms of the kingdom Plantae characteristically producing embryos , containing chloroplasts , having cell walls which contain cellulose , and lacking the power of locomotion . Although there has been a revolution in the biological sciences in the past twenty years , there is still a great deal that remains to be discovered . The completion of the sequencing of the genomes of rice and some agriculturally and scientifically important plants ( for example Physcomitrella patens ) has increased the possibilities of plant genetic ___MASK1___ immeasurably . A crossbreed or crossbred usually refers to an organism with purebred parents of two different breeds , varieties , or populations . " Crossbreeding ", sometimes called " ___MASK15___ crossbreeding ", refers to the process of breeding such an organism , often with the intention to create offspring that share the traits of both parent lineages , or producing an organism with hybrid vigor . While crossbreeding is used to maintain health and viability of organisms , irresponsible crossbreeding can also produce organisms of inferior quality or dilute a purebred gene pool to the point of extinction of a given breed of organism . Meteorology is the interdisciplinary scientific study of the atmosphere . The study of meteorology dates back millennia , though significant progress in meteorology did not occur until the 18th century . The 19th century saw modest progress in the field after weather observation networks were formed across broad regions . ___MASK62___ attempts at prediction of weather depended on historical data . It wasn ' t until after the elucidation of the laws of ___MASK72___ and , more particularly , the development of the computer , allowing for the automated solution of a great many equations that model the weather , in the latter half of the 20th century that significant breakthroughs in weather forecasting were achieved . Animal husbandry is the management and care of farm animals by human beings , in which genetic qualities and behavior , considered to be advantageous to humans , are further developed . The term can refer to the practice of selectively breeding and raising livestock to promote desirable traits in animals for utility , sport , pleasure , or ___MASK1___ . Robert Bakewell ( 23 May 1725 -- 1 October 1795 ) was a British agriculturalist , now recognized as one of the most important figures in the British Agricultural Revolution . In addition to work in agronomy , Bakewell is particularly notable as the first to implement systematic selective breeding of livestock . His advancements not only led to specific improvements in sheep , cattle and horses , but contributed to ___MASK65___ knowledge of artificial selection . Sometimes terms which refer to branches of soil ___MASK39___ , such as pedology ( formation , chemistry , morphology and classification of soil ) and edaphology ( influence of soil on organisms , especially plants ), are used as if synonymous with soil ___MASK39___ . The ___MASK17___ of names associated with this discipline is related to the various associations concerned . Indeed , engineers , agronomists , chemists , geologists , physical geographers , ecologists , biologists , microbiologists , sylviculturists , sanitarians , archaeologists , and specialists in regional planning , all contribute to further knowledge of soils and the advancement of the soil sciences . In biology , offspring are the young born of living organisms , produced either by a single organism or , in the case of sexual reproduction , two organisms . Collective offspring may be known as a brood or progeny in a more ___MASK65___ way . This can refer to a set of simultaneous offspring , such as the chicks hatched from one clutch of eggs , or to all the offspring , as with the honeybee . Selective breeding ( also called artificial selection ) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits ( characteristics ) by choosing which typically animal or plant males and females will sexually reproduce and have offspring together . Domesticated animals are known as breeds , normally bred by a professional ___MASK38___ , while domesticated plants are known as varieties , cultigens , or cultivars . Two purebred animals of different breeds produce a crossbreed , and crossbred plants are called hybrids . Flowers , vegetables and fruit - trees may be bred by amateurs and ___MASK52___ or non - ___MASK52___ professionals : ___MASK30___ crops are usually the provenance of the professionals . Earth ___MASK39___ or geoscience is a widely embraced term for the fields of ___MASK39___ related to the planet Earth . Earth ___MASK39___ can be considered to be a branch of planetary ___MASK39___ , but with a much older history . There are both reductionist and holistic approaches to Earth sciences . The Earth sciences can include the study of geology , the lithosphere , and the large - scale structure of the Earth ' s interior , as well as the atmosphere , hydrosphere , and biosphere . Typically , Earth scientists use tools from geography , chronology , ___MASK72___ , chemistry , biology , and mathematics to build a quantitative understanding of how the Earth system works and evolves . Agronomy ( Ancient Greek  " agrós " ' field ' +  " nómos " ' law ') is the ___MASK39___ and technology of producing and using plants for food , fuel , fiber , and land reclamation . Agronomy has come to encompass work in the areas of plant genetics , plant ___MASK47___ , meteorology , and soil ___MASK39___ . It is the application of a combination of sciences like biology , chemistry , economics , ecology , earth ___MASK39___ , and genetics . Agronomists of today are involved with many issues , including producing food , creating healthier food , managing the environmental impact of agriculture , and extracting energy from plants . Agronomists often specialise in areas such as crop rotation , irrigation and drainage , plant breeding , plant ___MASK47___ , soil classification , soil fertility , weed control , and insect and pest control . A ___MASK38___ is a person who selectively breeds carefully selected mates , normally of the same breed to sexually reproduce offspring with specific , consistently replicable qualities and characteristics . This might be as a ___MASK29___ , agriculturalist , or hobbyist , and can be practiced on a large or small scale , for food , fun , or profit . Animal breeding is a branch of animal ___MASK39___ that addresses the evaluation ( using best linear unbiased prediction and other methods ) of the genetic value ( estimated breeding value , EBV ) of livestock . Selecting for breeding animals with superior EBV in growth rate , egg , meat , milk , or wool production , or with other desirable traits has revolutionized livestock production throughout the world . The scientific theory of animal breeding incorporates population genetics , quantitative genetics , statistics , and recently molecular genomics and is based on the pioneering work of Sewall Wright , Jay Lush , and Charles Henderson . A cultigen ( from the Latin " cultus "  cultivated , and " gens "  kind ) is a plant that has been deliberately altered or selected by humans ; it is the result of artificial selection . These " man - made " or anthropogenic plants are , for the most part , plants of commerce that are used in horticulture , agriculture and ___MASK74___ . Because cultigens are defined by their mode of origin and not by where they are growing , plants meeting this definition remain cultigens whether they are naturalised in the wild , deliberately planted in the wild , or growing in cultivation . Cultigens arise in the following ways : selections of variants from the wild or cultivation including vegetative sports ( aberrant growth that can be reproduced reliably in cultivation ); plants that are the result of plant breeding and selection programs ; genetically modified plants ( plants modified by the deliberate implantation of genetic material ); and graft - chimaeras ( plants grafted to produce mixed tissue , the graft material possibly from wild plants , special selections , or hybrids ).