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Last Word

Are birds that walk more advanced than those that hop?

In the bush in Australia, there are two types of birds: those that walk, such as magpies, and those that hop, such as kookaburras. Is one of these groups more advanced than the other?

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Do the different causes of headaches create pain in different places?

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Are tandems really more efficient than regular bikes (continued)?

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This week鈥檚 new questions

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Why do cabbages exist when their shape prevents photosynthesis?

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Why does light reflect in a mirror but go straight through glass?

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This week鈥檚 new questions

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What makes some people short-sighted and others long-sighted?

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Are lids getting harder to open? (continued)

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To brew the best coffee, must you start with cold water?

Connoisseurs often prefer the cold brew method, but do you really need cold water for good coffee?

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This week鈥檚 new questions

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Why does milk spill over when it boils?

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Why don’t we make disease cures that are themselves infectious?

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What would it look like if dark matter fell into a black hole?

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