Food chains usually consist of 4 to 5 levels due to energy inefficiencies. Each level only transfers about 10% of its energy to the next, making it increasingly difficult to support organisms at higher trophic levels. This phenomenon highlights the role of primary producers in sustaining ecosystems. ;
Food chains rarely exceed 4 to 5 levels primarily due to energy inefficiencies, where only about 10% of energy transfers from one level to the next. This significant energy loss means that higher trophic levels have insufficient energy to sustain more organisms. Thus, ecosystems typically support only a limited number of levels, highlighting the importance of primary producers.
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