《中英對照讀新聞》Gene studies confirm "out of Africa" theories／基因研究證實「人類源自非洲」的理論

◎胡立宗

Two big genetic studies confirm theories that modern humans evolved in Africa and then migrated through Europe and Asia to reach the Pacific and Americas.

兩項大型基因研究證實，現代人是在非洲演化，然後向歐洲及亞洲遷徙，而到達太平洋（大洋洲）及美洲。

The two studies also show that Africans have the most diverse DNA, and the fewest potentially harmful genetic mutations.

這兩項研究也顯示，非洲人的DNA最為多元，潛在有害的基因突變也最少。

One of the studies shows European-Americans have more small mutations, while the others show Native Americans, Polynesians and others who populated Australia and Oceania have more big genetic changes.

其中一項研究顯示，歐美人士出現較多的局部（基因）突變，美洲原住民、玻里尼西亞人，及住在澳洲和大洋洲的人則出現較大規模的基因改變。

The studies, published in the journal Nature, paint a picture of a population of humans migrating off the African continent, and then shrinking at some point because of unknown adversity.

這兩項刊登在「自然」期刊的研究描繪出的圖像是，一群人類從非洲大陸往外遷徙，然後在某個時間等因為未知的因境，導致人口減少。

Later populations grew and spread from this smaller genetic pool of founder ancestors--a phenomenon known as a bottleneck.

之後的世代人口再度增加，從這個較小的先祖基因庫中擴散開來—這個現象被稱為「瓶頸」。

Populations that remained in Africa kept their genetic diversity--something seen in many other studies.

但留在非洲的人類則仍保有基因多元性—這一點已見諸許多其他研究。

新聞辭典

diverse：形容詞，不同的、互異的、多樣的；名詞為 diversity；biodiversity（生物多樣性）。

native：形容詞，天生的、本國的、特有的、原產的、天然的；名詞，本地人、本國人、原生的動植物。native speaker of a language（以某種語言為母語的人）。

adversity：名詞，逆境、厄運、災難。例句︰A friend in time of adversity is a friend indeed.（有難同當才是真朋友。）

來源：自由時報

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