Premature birth is the main cause of perinatal mortality.

早产是围产期死亡的主要原因。

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The grass grows up to four metres tall and burns fiercely, creating super hot fires that cause catastrophic tree mortality.

草长到四米高，剧烈燃烧，所造成的特大火灾导致树木灾难性的死亡。

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Phytoplankton cause mass mortality in other ways.

浮游植物还以其他方式造成大量死亡。

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"It does not really matter because in the best case scenario we have today,we will still have a moderate virus that is projected to cause several million deaths extra deaths than the usual influenza annual mortality, which means that even in the best-case scenario, we do have an emergency on our hand,"

VOA: standard.2009.09.04

Finally, and most important, recent studies have shown convincing evidence that cardio-respiratory fitness is a much stronger predictor of longevity and reduced risk of cardiovascular mortality and all-cause mortality than BMI.

FORBES: How Useful Is Body Mass Index In Predicting Long-Term Health?

"Collisions with ships are the number one cause of mortality, and entanglement in fishing gear is the number two cause, " Lecky said.

CNN: Plan to save whales strangling in red tape

Vitamin D has been convincingly correlated with all-cause mortality, with certain cancers, and with multiple sclerosis.

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