A landrace is a domesticated, locally adapted, often traditional variety of a species of animal or plant that has developed over time, through adaptation to its natural and cultural environment of agriculture and pastoralism, and due to isolation from other populations of the species. Landraces are distinct from cultivars and from standard breeds. A significant proportion of farmers around the world grow landrace crops, and most plant landraces are associated with traditional agricultural systems. Landraces of many crops have probably been grown for millennia. Increasing reliance upon modern plant cultivars that are bred to be uniform has led to a reduction in biodiversity, because most of the genetic diversity of domesticated plant species lies in landraces and other traditionally used varieties. Some farmers using scientifically improved varieties also continue to raise landraces for agronomic reasons that include better adaptation to the local environment, lower fertilizer requirements, lower cost, and better disease resistance. Cultural and market preferences for landraces include culinary uses and product attributes such as texture, color, or ease of use. Plant landraces have been the subject of more academic research, and the majority of academic literature about landraces is focused on botany in agriculture, not animal husbandry. Animal landraces are distinct from ancestral wild species of modern animal stock, and are also distinct from separate species or subspecies derived from the same ancestor as modern domestic stock. Not all landraces derive from wild or ancient animal stock; in some cases, notably dogs and horses, domestic animals have escaped in sufficient numbers in an area to breed feral populations that form new landraces through evolutionary pressure. Characteristics There are differences between authoritative sources on the specific criteria which describe landraces, although there is broad consensus about the existence and utility of the classification. Individual criteria may be weighted differently depending on a given source's focus (e.g., governmental regulation, biological sciences, agribusiness, anthropology and culture, environmental conservation, pet -keeping and -breeding, etc.). Additionally, not all cultivars agreed to be landraces exhibit every characteristic of a landrace. General features that characterize a landrace may include: It is morphologically distinctive and identifiable (i.e., has particular and recognizable characteristics or properties), yet remains "dynamic". It is genetically adapted to, and has a reputation for being able to withstand, the conditions of the local environment, including climate, disease and pests, even cultural practices. It is not the product of formal (governmental, organizational, or private)