Now they are also highly evolved to photosynthesis and they are one of the most productive photosynthetic groups of organisms on earth. 20 to 25 percent of the total global net primary production is done by these organisms. Several of their adaptations allow them to do this. Three of the big ones are that they are able to store energy as oils which also helps them with staying higher in the water column,they have the strong silica frustules that protects them from a large amount of predation (more on the frustules in reproduction and facts), and they are able to grow virtually everywhere on the plant. There are species of diatoms that live in the soil, the snow, ice, arctic waters, Antarctic waters, tropical waters, rivers, and possible even more places (more at habitat). This allows them to be extremely prolific primary produces and a large portion of the base in many ecosystems.