题干

在下面一段文字横线处补写恰当的语句,使整段文字语意完整连贯,内容贴切,逻辑严密。每处不超过15个字。

是什么外在因素促使早期灵长类进化出了特殊的性征,即它们带手指的前肢。科学家给出了一个出其不意的答案:①____。开花植物进化出更大、更鲜美的果实,②____;而作为回报,这些灵长类动物频繁地为植物传花授粉——它们吞食植物果实后,将种子四处播撒,使得这些植物非但没有灭绝,③____,甚至衍生出了新种。就这样,灵长类动物进化出了可以抓握的手。

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答案(点此获取答案解析)

与开花植物有关,吸引灵长类动物来吃,反而大量繁殖

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    I loved my aunt Suzy. She was such a kind old lady. I loved going to her house on holiday. She had been sick for the last few years and, though my job had taken me away across the town, I tried to visit her as much as possible. I helped with the shopping, the cooking and the cleaning and taking her pet cat Mazy to the vet.

    Sad as her passing away was, what happened to Mazy was even more worrying. Because aunt Suzy had no children, there wasn't anyone who seemed to care for her beloved cat friend. I would have taken her in a short time, but my apartment doesn't allow pets. First, we talked with her neighbors. Mr. Jenkins, who was alone and lived across the street, wasn't interested. Joe and Sally who lived next door had a small child with serious skin allergies(过敏症). My aunt's best friend Molly who had lived just down the road was unable to take care of herself as she had serious health problems.

    Second, we thought about our family members. My brother Bobby and his wife Jill were eliminated at once as they aren't cat people. My cousin in California was a bit interested, but we weren't sure about the trip as Mazy was nearly as old as my aunt (in cat years!). Finally, we came to the local humane society to see whether they would be able to help her find a new home. The problem was that most people and families only welcomed a smart little cat into their home, not a dull old one.

    In the end, we had to put Mazy to sleep. I had spoken with the vet and realized it was possible for the best. It was so hard to lose aunt Suzy and then have nowhere for Mazy to live. A few months went by and I had gone to my aunt's house to clear out some of her belongings. I happened to see her mailman. Jerry and we started to talk about my aunt when he asked about Mazy. I told him that we had to put Mazy to sleep because we couldn't find a home for her. Jerry got really quiet. “I promised Suzy that if anything ever happened to her, I'd take care of Mazy”, he said sadly. “Suzy always said she'd told her lawyer the arrangement.”

    Hearing this, my heart sank to my feet and I almost cried. The saddest part, I realized, was this all could have been avoided. I guess we were just so busy in those final months that we didn't think about it. We could have called my aunt's lawyer to take care of it in less than 10 minutes. I'll never forgive myself for not thinking of it sooner. And I'll never forgive myself for losing Mazy.