Most of the fossils seen in Paleozoic rocks are invertebrate animals lacking backbones, such as corals, mollusks and trilobites.

大部分在古生代岩层中发现的化石都是没有脊骨的无脊椎动物，例如珊瑚、软体动物和三叶虫。

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Such a close co-existence with a photosynthetic organism has previously been found in invertebrates, such as corals, but never in a vertebrate.

这种和光合作用微生物的亲密共存现象曾被发现存在于无脊椎动物中，比如说珊瑚，但是从未在脊椎动物中发现过。

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Top of the list was ecosystem collapse, such as deforestation and the demise of corals; second were health and diseases, such as Sars and Aids; and third was global poverty.

高居榜首的是生态系统的崩溃，如滥砍滥伐和珊瑚死亡；第二是健康与疾病，如非典和艾滋病；第三是全球性贫困。

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"We must focus on helping corals to adapt to climate change and on diverting people away from destructive practices such as overfishing, " Linden said.

CNN: World's corals reefs are vanishing, report says