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.

· · 来源：learn资讯

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“The Air F。业内人士推荐服务器推荐作为进阶阅读

Карина Черных (Редактор отдела «Ценности»)

Tom Hanks, who played Lovell in the 1995 movie Apollo 13, called the astronaut one of those people "who dare, who dream, and who lead others to the places we would not go on our own".

Australian

對華逆差超千億美元，默茨首次訪華能否反轉中德「零和」競爭？