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Large sharks hunting each other ‘may be more common than thought’
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CO2 increasing 10 times faster than any point in last 50,000 years – study
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Easily-guessed passwords banned
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Extinct giant salmon ‘used tusk-like tooth for fighting and not catching prey’
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Life on Earth ‘under siege’ from humans, say scientists
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Adding too much water to whiskies can make them taste the same, study suggests
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Workers 'are better at their jobs if they have sex the night before'
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