Dogs act like toddlers when you need help - but cats just watch. Scientists compared 3 groups: pet dogs, cats, and human toddlers in an experiment where a human parent hides and pretends to look for an object. 75% of dogs and children helped. Cats only helped if it was in their personal interest.

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外围的物理装备拉满了，机器的内功自然也得跟上。

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A microfluidics chip enables researchers to manipulate and study individual cells, without the use of agar at all. Credit: Brouzes E. et al. PNAS (2009).