Definission: A rock formed by subjecting any rock type (including previously-formed metamorphic rock) to different temperature and pressure conditions than those in which the original rock was formed. These temperatures and pressures are always higher than those at the Earth's surface and must be sufficiently high so as to change the original minerals into other mineral types or else into other forms of the same minerals (e.g. by recrystallisation).
Definission: a plant that produces wood as its structural tissue. Wood is a structural cellular adaptation that allows woody plants to grow from above ground stems year after year, thus making some woody plants the largest and tallest terrestrial plants. Wood is usually primarily composed of xylem cells with cell walls made of cellulose and lignin
Definission: This organism produces this material or substance, either during its life or after death. A produces B if some process that occurs in A has output B.
Definission: A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)
