# Serpentinite **Domain:** Geology / Ecology / Constraint **Doc Type:** Canonical Material Node **Maturity:** Developed ## Definition **Serpentinite** is rock produced by hydration and metamorphic alteration of ultramafic material from Earth's mantle or oceanic lithosphere. Weathering commonly produces soils low in calcium and major plant nutrients and high in magnesium and metals such as nickel and chromium. ## Evolutionary Nexus Those chemical constraints exclude many generalist plants while supporting specialized and endemic communities. In [[articles/The Evolutionary Roots of Silicon Valley|The Evolutionary Roots of Silicon Valley]], serpentine outcrops become a local laboratory for [[wiki/Ecological Constraint|Ecological Constraint]] and [[wiki/Speciation Moment|speciation under constraint]]. Constraint alone does not guarantee novelty. Variation, inheritance, population history and time remain necessary. The correct computational analogy is therefore not “bad conditions make better systems,” but that a fitness landscape changes which variants remain viable. ## Sources / Provenance - U.S. Geological Survey, _Geology of the Golden Gate Headlands_: https://pubs.usgs.gov/bul/b2188%202/b2188ch3.pdf - Stanford Habitat Conservation Plan, “Serpentine Grasslands”: https://hcp.stanford.edu/serpentine.html ## See Also [[wiki/Serpentine Ecology|Serpentine Ecology]], [[wiki/Bay Checkerspot Butterfly|Bay Checkerspot Butterfly]], [[wiki/Selection Gradient|Selection Gradient]], [[wiki/Adaptive Structure|Adaptive Structure]]