【摘 要】
：
K-T边界可以提供极有价值的生物灭绝事件的证据,但是关于生物消失的强度、速度和选择性仍然存在争论,这些争论的焦点一般是化石记录的准确性以及取样的偏差和再造作用的影响
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K-T边界可以提供极有价值的生物灭绝事件的证据,但是关于生物消失的强度、速度和选择性仍然存在争论,这些争论的焦点一般是化石记录的准确性以及取样的偏差和再造作用的影响。有证据说明脊椎动物和无脊椎动物化石群分布区的选择性,并且这个事件好像对于食物链中依赖初级生产力
K-T borders can provide valuable evidence of a biological extinction event, but there is still debate about the strength, speed, and selectivity of extinctions, and the focus of these debates is generally on the accuracy of fossil records and the effects of sampling bias and rework. There is evidence of selectivity in the distribution of vertebrate and invertebrate fossil populations, and this event seems to be an indicator of reliance on primary productivity in the food chain
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