i suppose i am a little slow on the uptake

  • 1geochronology — geochronologic /jee oh kron l oj ik/, geochronological, adj. geochronologist, n. /jee oh kreuh nol euh jee/, n. the chronology of the earth, as based on both absolute and relative methods of age determination. [1890 95; GEO + CHRONOLOGY] * * *… …

    Universalium

  • 2Marine habitats — Coral reefs provide marine habitats for tube sponges, which in turn become marine habitats for fishes Littoral zone …

    Wikipedia