Insects are fairly low down (on) the food chain.

在食物链中，昆虫是相当低的一级生物。

《牛津词典》

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He looked down to relieve the pain of his neck, and stared at the rusty chain at his feet, which coiled around a metal rod.

他低下了头来缓解脖子的疼痛，眼睛停留在脚下生锈的铁链上，那铁链绕在一根金属杆上。

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One recent story showed how "fence rustlers" are tearing down chain-link fences to sell to receivers of stolen goods.

FORBES: Press Lords

But researchers think its origins lie further down the food chain - in plants, small mammals or insects.

BBC: News | Africa | Fighting back at ebola

Further down the supply chain, timber-dealers and factories are often certified largely on the strength of documents which may be illegally bought.

ECONOMIST: Western consciences can do only so much to conserve forests