Sphagnum ones ("Rigida" and "Squarrosa") has been clarified using molecular phylogenetics. All but two species normally identified as "Sphagnum" reside in one clade; two other species have recently been separated into new families within the Sphagnales reflecting an ancestral relationship with the Tasmanian endemic "Ambuchanania" and long phylogenetic distance to the rest of "Sphagnum". Within main clade of "Sphagnum", phylogenetic distance is relatively short, and molecular dating methods suggest nearly all current "Sphagnum" species are descended from a radiation that occurred just 14 million years ago. "Sphagnum" mosses occur mainly in the Northern Hemisphere in peat bogs, conifer forests, and moist
Oxy-fuel welding and cutting is what chemically combines with the fuel to produce the heat for welding. This is called 'oxidation', but the more specific and more commonly used term in this context is 'combustion'. In the case of hydrogen, the product of combustion is simply water. For the other hydrocarbon fuels, water and carbon dioxide are produced. The heat is released because the molecules of the products of combustion have a lower energy state than the molecules of the fuel and oxygen. In oxy-fuel cutting, oxidation of the metal being cut (typically iron) produces nearly all of the heat required to "burn" through