英語四級閱讀練習(xí)附答案-95 基因差異大易成夫妻

　　Opposites Attract in Human Search for Mate

 

　　When it comes to choosing a mate, opposites really do attract, according to a 8razilian study that found people are subconsciously more likely to choose a partner whose genetic make-up is different to their own.

　　They found evidence that married couples are more likely to have genetic differences in a DNA region governing the immune system than were randomly matched pairs.

　　This was likely to be an evolutionary strategy to ensure healthy reproduction because genetic variability is an advantage for offspring, Maria da Graca Bicalho and her col1eagues at the University of Parana in Brazil reported.

　　"Although it may be tempting to think humans choose their partners because of their similarities, our research has shown clear1y that it is differences that make for successful reproduction, and that the University drive have healthy children is important when choosing a mate." Bicalho said in a statement.

　　Scientists said it was not c1ear what signals attract the body to people who are genetical1y dissimilar to themselves, but suggested body odor or even face structure could play a role.

　　Bicalho said the team compared genetic data from 90 married couples with data from 152 random1y generated control couples.

　　They found the real couples had significantly more dissimilarities in MHC.

　　"Parents with dissimilar (genetic regions) could provide their offspring with a better chance to ward infections off because their immune system genes are more diverse," they wrote in a summary.

　　Previous studies have suggested animals may use body odor as a guide to identify possible mates as being genetically similar or dissimilar, she added, but other physical factors may also be involved.

　　"Other cues such as face symmetry might play a role as well, but they are still in the field of speculation," she said.

　　基因差異大，容易成夫妻

　　人們在選擇伴侶時，更容易被與自己基因差異大的人吸引。巴西一項最新研究表明，人們總是下意伊地選擇基因構(gòu)成和自己相異的人做伴侶。

　　研究結(jié)果表明，與隨機配對的搭檔相比，夫妻二人控制免疫系統(tǒng)的DNA區(qū)域中基因差異更大。

　　巴西巴拉那大學(xué)的瑪麗亞達·格拉薩·比卡盧和同事在研究報告中指出，這可能是人類確保生育健康的進化策略，因為基因的差異性對后代有利。

　　比卡盧在聲明中稱：“雖然大家更愿意相信人們會選擇相似的人做伴侶，但我們的研究明確顯示，存在差異的伴侶更能成功生育后代，而直選擇伴侶時，這種潛在的生育健康后代的意識很重要。”

　　科學(xué)家稱不清楚是何種身體信息使人們吸引到基因相異的人，但表示體味甚至臉型都可能有關(guān)。

　　比卡盧稱，研究小組將90對夫妻的基因與152對隨機配對的“夫妻”的基因進行了對比。

　　研究人員發(fā)現(xiàn)，真夫妻的主要組織相容性復(fù)合體差異更顯著。

　　研究人員在一份總結(jié)中寫道：“基因相異的夫妻所生育的后代更不容易生病，因為他們的免疫系統(tǒng)更加多樣化。”

　　比卡盧補充稱，此前研究己證實，動物用體味來識別潛在伴侶的基因與自己的異同，但其他身體特征可能也起作用。

　　她說：“其他因素，比如臉型是否對稱都可能與之相關(guān)，但還沒有得到證實。”

　　句型講解：

　　1. They found evidence that married couples are more likely to have genetic differences in a DNA region governing the immune system than were randomly matched pairs.

　　本句是一個復(fù)合句，主句是They found evidence。 that引導(dǎo)同位語從句，解釋說明evidence。其中g(shù)overning the immune system現(xiàn)在分詞短語作后置定語修飾DNA region。

　　語法重點：同位語從句，分詞短語作定語

　　2. Although it may be tempting to think humans choose their partners because of their similarities, our research has shown clear1y that it is differences that make for successful reproduction, and that the University drive have healthy children is important when choosing a mate.

　　本句是一個復(fù)合句。 Although引導(dǎo)讓步狀語從句。后面第一個that引導(dǎo)賓語從句，作shown的賓語，其中it is...that...是強調(diào)句型，對difference進行強調(diào)。第三個that同樣引導(dǎo)賓語從句，作shown的賓語。其中to have healthy children不定式短語作后置定語，修飾 subconscious drive。 when choosing a mate為現(xiàn)在分詞短語做時間狀語。

　　語法重點：讓步狀語從句，賓語從句，強調(diào)句型，不定式短語作定語