53. What did the author and colleagues identify in their recent research?
- A. A gene-related selfish behavior in preschool children.
- B. Key factors that determine one's altruistic behavior.
- C. A specific gene associated with altruistic behavior.
- D. Roles played by genes in shaping one's character.
答案：C
答案句：My colleagues and I recently identified a gene linked to altruistic(利他的)behavior and found that a particular variant of it was associated with more selfish behavior in preschoolers.
A
参考译文：我和同事们最近识别出一个与利他行为相关的基因，并发现该基因的一个特定变体与学龄前儿童更自私的行为有关。
定位线索：题干“author and colleagues”→答案句“My colleagues and I”；文中“identified a gene linked to altruistic behavior”对应选项C“A specific gene associated with altruistic behavior”。
解析：题干问作者和同事最近研究的发现，答案句直接说“identified a gene linked to altruistic behavior”，即识别出与利他行为相关的基因，对应选项C“A specific gene associated with altruistic behavior”。选项A“selfish behavior in preschool children”只是基因变体的关联，不是主要发现；选项B“key factors”范围过大；选项D“roles played by genes”过于笼统，未具体到基因。
54. What do we learn from evolutionary scientists about cooperative behavior?
- A. It may have initially originated in individuals linked by blood.
- B. It may have caused the diversification of communities.
- C. It helps to build relationships among blood-related people.
- D. It guarantees the achievement of goals otherwise unattainable.
答案：A
答案句：According to evolutionary scientists, cooperative behavior may have evolved first among relatives to promote the continuation of their genetic line.
参考译文：根据进化科学家的观点，合作行为可能首先在亲属之间进化，以促进其基因线的延续。
定位线索：题干“evolutionary scientists”→答案句“According to evolutionary scientists”；文中“evolved first among relatives”对应选项A“initially originated in individuals linked by blood”。
解析：题干问从进化科学家那里了解到的合作行为，答案句明确指出“cooperative behavior may have evolved first among relatives”，即合作行为首先在亲属间进化，对应选项A“It may have initially originated in individuals linked by blood”。选项B“caused the diversification”因果颠倒，原文说社区多样化后合作扩展；选项C“build relationships among blood-related people”范围缩小，原文说合作扩展到非血缘；选项D“guarantees”程度过重，原文说“higher chances of survival”。