(圖援用自原文)
Human culture and language may be the result of ‘self-domestication’: an evolutionary process that leads to less aggressive and more prosocial individuals. A research team led by the Max Planck Institute for Psycholinguistics in Nijmegen argues that elephants—like humans and bonobos—may also be self-domesticated.
人類的文化及語言或許是‘自我馴化’的結果：一種導致較少攻擊性及更多親社會的個體。一支由位於荷蘭海爾德蘭省奈梅亨市，馬克斯普朗克心理語言學研究所領導的研究團隊認為，大象(與人類及倭黑猩猩一樣)可能也是自我馴化的。
Elephants show many traits associated with self-domestication, such as prosocial behaviour, playfulness and complex communication skills. This makes elephants an interesting new animal model for the evolution of prosociality.
大象展現諸多與自我馴化相關的特點，諸如親社會的行為、愛嬉戲及複雜的溝通技巧。這使大象成為一種，親社會性演化之引人好奇的新動物模型。
Humans have complex social behavior, diverse communication skills, and a capacity for highly developed tool use. Researchers argue that human evolution may resemble the process of animal domestication, where less aggressive animals are favoured.
人類具有複雜的社會行為、多樣的溝通技巧及高度發展的工具使用能力。研究人員們認為，人類演化可能類似，較少攻擊性動物受到青睞之動物馴化的過程。
In the same way, human evolution may be the result of natural selection for more prosocial and cooperative individuals. Such individuals are more likely to interact with others and form complex communities, in which they can learn from each other.
同樣地，就更多親社會及合作的個體而言，人類的演化可能是自然選擇的結果。如此的個體更有可能與其他人互動，及形成他們能相互學習的複雜團體。
“The theory of self-domestication is hard to test”, says first author Limor Raviv. “This is because only one other species besides humans has been argued to be self-domesticated: bonobos.” Could elephants be the first non-primate animal model for self-domestication? Raviv and her colleagues set out to study the similarities between elephants, bonobos, and humans, and followed up with a genetic analysis.
首要撰文人Limor Raviv宣稱：「自我馴化理論不易驗證。這是因為，除了人類之外，僅一種其他物種，被認為是自我馴化的：也就是，倭黑猩猩。」大象能是第一種自我馴化的非靈長類動物模型嗎？Raviv及其同僚們著手研究，大象、倭黑猩猩及人類之間的相似處，且隨後進行了遺傳分析。
The team found that elephants show many hallmarks of domestication. Similar to humans and bonobos, they have low levels of aggression, high levels of empathic and prosocial behaviour, an extended juvenile period, and increased playfulness and curiosity.
該團隊發現，大象展現諸多馴化的特點。類似人類及倭黑猩猩，它們具有低的攻擊性、高的同理心與親社會行為、一個延長的少年期及增強的愛嬉戲與好奇心。
Elephants form coalitions, ‘babysit’ calves, offer protection and comfort to others, and help dying or ill members of their herds—and even the occasional outsider. There is also evidence that elephants are both self-aware and sensitive to the needs and wants of others.
大象結成聯盟，“照顧”小象、為其他大象提供保護與慰藉及幫助垂死或其群中的生病成員，甚至偶爾的外來大象。也有大象兼具，自我意識及對其他大象的困境與需要敏感的證據。
Another important hallmark is elephants’ ability to learn from each other. Behaviours that are often innate in other animals—such as what to eat or how to raise offspring—are socially transmitted in elephants.
另一項重要特點，是大象相互學習的能力。通常在其他動物中，是天生的行為(諸如吃什麼或如何養育後代)。在大象中，是透過社交傳遞的。
Elephants also have a sophisticated multimodal communication system with an extensive vocal repertoire, ranging from trumpets and roars to low-frequency rumbles. For example, elephants in Kenya have different alarm calls for humans and for bees. Their varied and combined calls even show signs of grammar.
大象也有複雜之具有從喇叭聲、咆哮聲到低頻隆隆聲等，廣泛發聲能力的多樣式溝通體系。譬如，於肯亞的大象，對人類及對蜜蜂，發出不同的警報聲。它們富於變化及複合性的叫聲，甚至展示語法的跡象。
Finally, the team found several candidate genes associated with domestication in elephants. The authors propose that self-domestication in elephants could be related to their massive size and relative strength.
最後，該團隊在大象中，發現若干與馴化相關的候選基因。此些撰文者們認為，於大象中，自我馴化可能與其龐大的體型及相對的力量有關。
“This means that elephants are generally less worried about evading or fighting other animals for their survival”, Raviv explains. “This kind of ‘safe environment’ could relax selective pressures for aggression, free cognitive resources, and open up more opportunities for exploration, communication, and play.”
Raviv解釋：「這意味著，大象通常較不擔心，為了生存逃避或與其他動物搏鬥。這種‘安全環境’能減輕攻擊性行為的選擇性壓力(一種導致特定表型，在某些環境條件下，更有利的演化力)、釋放認知資源，及為探索、溝通與遊戲開啟更多機會。」
“Our hypothesis of self-domestication in elephants has exciting potential for future research in other species”, concludes Raviv. “It can inform our understanding of the evolution of prosocial behaviour across evolutionarily distant species, providing important insights into convergent evolution.”
Raviv下結論：「我們有關大象中自我馴化的假設，對於未來在其他物種中的研究，具有令人振奮的潛力。它能賦予我們，有關跨越演化上疏遠物種之親社會行為演化的瞭解，提供趨同演化的重要洞察力。」
網址：https://www.mpi.nl/news/elephants-new-model-understanding-human-evolution
翻譯：許東榮
文章定位：
