How do corals grow? A single polyp builds a cup-shaped skeleton around its soft body. This polyp can multiply and eventually many polyps form a large mass of coral rock. In most corals, new polyps form by branching off from old polyps. They bud off from their parent much as a bud sprouts from the side of a tree. As the polyps grow, they build new cup skeletons on top of the old ones. Polyps always grow at the surface of the colony. Below them, layer upon layer of old skeletons make up the coral rock. If we cut through the coral rock, we see skeleton growth lines showing how the polyps grew and multiplied. The living surface of a hard coral can be green, pink, yellow or even blue. But the coral rock inside is white (or, in the unusual case of blue coral, the inside is blue) because only the living polyps have color. Faapefea ona la 'amu? O polipo taitasi e fauina o latou atigi pito mai i fafo lea e vaaia e tatou ma taua o le 'amu. O le atigi e faata'amilomilo i le tino galemulemu o le 'amu aua le puipuia o le puipuia o le polipo. E amata o tasi le polipo i se nofoaga ae mafai ona faateleina e ala lea i le tatupu ifo o tamai polipo mai le polipo tele e faapei o tamai la'au e tatupu ifo i le 'aa ole la'au tele. O le tele ma le tele o nei polipo e nonofo faatasi i koloni ma avea ai se nofoaga e tele ai ni 'amu ma a'au tele. E vaaia le tutupu ifo o 'amu fou i luga o 'amu ua pepe po ua foliga i maa. O le tele o 'amu i o tatou a'au ua pepe ua na'o se pito i luga o ola ai naitamai 'amu. A tatou tata'eina se oga'amu, e mafai ai ona vaaia ai ni laina e iloa ai le tele o polipo na ola i totonu o se'amu e tasi. Ua na'o le vaega o le 'amu o ola e mafai ona vaaia o lanu mai, e i ai lanu meamata, piniki, samasama, ma le lanu moana; ao le tele lava o 'amu ua lanu papa'e, o 'amu ia ua pepe. Pehea e ulu ai ke ko'a? Kukulu ho'okahi uku ko'ako'a i kekahi iwi e like me ke ki'aha a puni o kona kino palupalu. Ua hiki i keia ke ho'onuinui a 'auane'i ho'okumu i kekahi papanui puko'a. Ua ho'oulu ka hapanui o na ko'a mai na uku ko'ako'a kahiko mai. Ho'okiupu lakou mai ko lakou mau makua mai e like me kakahi kumula'au. I ka ulu'ana o na uku ko'ako'a, kukulu lakou i na 'iwi a'apu hou ma luna o na mea kahiko. Ulu mau na uku ko'ako'a i mau ka papaluna o ka hui. Ma lalo, he papa ma he papa, ho'ohana na iwi kahiko i ke ko'apa'a. Ina kalai i ke ko'apa'a, 'ike kakou i na laina uluiwi e he'ike nei i ka ulu ana o na uku ko'ako'a. Ua hiki i ka papaola o ke ko'a e loa'a i ka 'oma'oma'o, 'akala, lenalena, ai'ole uliuli. Aka ua kea ka loko (koe na'e ke ko'a uliuli) no ka mea ua loa'a i na ko'aola ka waiho'olu'u wale no.