美國科學研究稱地球正處於第六次動植物大滅絕過程
文章來源: 結誠晶 於
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華盛頓10月23日電 據美國每日科學網站日前報道,美國科學家說,地球正處於第六次動植物大滅絕的過程中,近50%的物種將消失。
報道援引美國加利福尼亞大學聖巴巴拉分校生態學、進化學和海洋生物學係副教授布拉德利·卡迪納爾說:“當前這場物種滅絕的罪魁禍首是人類活動,包括開采、製
造汙染以及我們今天正在做的很多事。在我們有生之年地球很可能失去一半的物種。我們希望搞清楚其中哪些值得我們最先給予保護。”
卡迪納爾解釋說,同今天的物種滅絕程度相近的上一次物種大滅絕發生在距今6500萬年前,被稱作“白堊紀——第三紀滅絕事件”,很可能是一顆隕星墜落地球造成的。這一事件因非鳥類恐龍滅絕而著名,但當時大量的植物物種也隨之滅絕。
鑒於當前的這場危機,加利福尼亞大學聖巴巴拉分校的生物學家為了確定哪些物種必須被拯救而夜以繼日地工作著。
根據當前研究結果,基因最獨特的物種是生態係統中最重要的物種。它們正是科學家建議列入最先保護名單的物種。科學家發現,有些物種在保護生態係統功能方麵比其他物種更重要,這些物種常常有獨特的基因。
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