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距今约３．６７亿年前发生的Ｆ－Ｆ生物集群灭绝事件是显生宙五大生物灭绝事件之一．这一事件对当时全球浅海壳相底栖生物的影响甚大，它使竹节石全部消失，泥盆纪的生物礁和泥盆纪特征的珊瑚、层孔虫、苔藓虫惨遭灭绝，腕足动物门中的无洞贝超科、五房贝超科和三叶虫的３个科和１个亚科以及菊石中的Ｍａｎｔｉｃｏｃｅｒａｓ等也难逃劫运． 地质历史时期生物的演化一般可分成灭绝期、残存期、复苏期和辐射期等４个发展阶段．晚泥盆世弗拉期（Ｆｒａｓｎｉａｎ）末为生物的集群灭绝期，大量的泥盆纪生物惨遭灭绝；法门期（Ｆａｍｅｎｎｉａｎ）的早、中期为生物的残存期，当时地球上的生物非常稀少而且十分单调；法门期的晚期则是生物的复苏期，这时出现了不少的新生属种．在泥盆纪－石炭纪之交，在生物的演化史上又发生了另一次集群灭绝事件，虽然这次灭绝事件的规模远不及Ｆ－Ｆ事件，但使不少法门期的生物惨遭恶运，使刚开始的生物复苏的势头又受到了挫折，中断了它向辐射阶段演化的进程． 关于引发Ｆ－Ｆ灭绝事件的机制目前仍存在着地外（ｅｘｔｒａ－ｔｅｒｒｅｓｔｒｉａｌ）和地内（ｔｅｒｒｅｓｔｒｉａｌ）两种不同的解释，前者是指小行星对地球的撞击，后者是指广泛的海侵、海平面升降、气候?
The extinction of the F-F biome from about 367 million years ago was one of the five major biological extinctions in the Phanerozoic. This event had great influence on the benthic marine benthic marine beings at that time in the world. It resulted in the disappearance of all the rhyolite. The reefs of Devonian and Devonian corals, laminanella and bryozoans were brutally extinct, In the hole-free superfamily Branch, five rooms Pui Branch and Trilobite three branches and a subfamily and ammonite in the Manticoceras, etc. also can not escape the robbery. The evolution of the organisms in geologic history can generally be divided into four stages of development: extinction, remnant, recovery and radiation. At the end of the Late Devonian Frasnian, a large number of Devonian beings were extinct during the extinction of living creatures. The early and mid-Famennian periods of living creatures were extremely rare and Very monotonous; late Famen period is the biological recovery period, when there are many newborn species. At the turn of the Devonian-Carboniferous, another cluster extinction took place in the evolutionary history of the creatures. Though the scale of this extinction event was far behind that of the F-F incident, many Famennian creatures were tragically killed, The momentum of the initial biological recovery has been frustrated again, interrupting its evolution to the radiation phase. There are still two different explanations about extra-terrestrial and terrestrial mechanisms concerning the initiation of F-F extinctions: the former refers to the impact of the asteroid on the earth and the latter refers to the extensive transgression of the sea Plane movements, climate?