2025年5月7日，Mpala研究中心Dustin R. Rubenstein研究团队在《自然》杂志发表论文，揭示了在合作繁殖的鸟类中起到相互帮助的神秘作用。

该课题组对超椋鸟（Lamprotornis superbthem）进行了为期20年的研究，研究了直接和间接适应度如何共同影响帮助行为。尽管该课题组研究人员发现了亲属偏向性帮助（证明了亲属选择），但尽管有机会帮助亲属，非亲属帮助也很常见。出乎意料的是，特定的一对通过在一生中交换社会角色来维持长期的互惠关系——这是一种微妙的互惠模式，需要几十年的观察才能发现。考虑到非亲缘帮助的频率以及亲缘和非亲缘之间相互帮助的发生，超椋鸟的帮助行为似乎受到直接适合度的很大影响。

然而，直接和间接适合度的相对重要性因帮助者的性别和分散历史而异。通过揭示长期互惠帮助的一个神秘而关键的作用，研究组认为互惠可能是一个未被充分认识的促进合作繁殖社会稳定的机制。

据悉，识别合作背后的机制是生物学的基础。脊椎动物中最复杂的合作形式出现在合作繁殖者身上，在这种合作中，帮助者放弃繁殖后代，而帮助抚养其他动物的后代，尤其是亲属的后代。然而，并不是所有的合作社会都是以亲属为基础的——近一半的鸟类和哺乳动物的合作繁殖者形成了混合亲属的社会，就像人类一样。在混合亲属社会中，当个体从亲属的优先帮助中获得间接适应度时，亲属选择就发生了，但帮助者也经常帮助非亲属，这突出了直接适应度在稳定合作社会中的潜在作用。

附：英文原文

Title: A cryptic role for reciprocal helping in a cooperatively breeding bird

Author: Earl, Alexis D., Carter, Gerald G., Berlinger, Arden G., Korir, Elkana, Shah, Shailee S., Watetu, Wilson N., Rubenstein, Dustin R.

Issue&Volume: 2025-05-07

Abstract: Identifying the mechanisms that underlie cooperation is fundamental to biology1. The most complex form of cooperation in vertebrates occurs in cooperative breeders, in which helpers forego reproduction and assist in raising the young of others, typically relatives2. Not all cooperative societies, however, are kin-based—nearly half of all avian3 and mammalian4 cooperative breeders form mixed-kin societies, much like those of humans5. Kin selection in mixed-kin societies occurs when individuals gain indirect fitness from the preferential helping of relatives6, but helpers also frequently assist non-kin7, highlighting a potential role for direct fitness in stabilizing cooperative societies7,8. Here, using a 20-year study of superb starlings (Lamprotornis superbus), we examined how direct and indirect fitness jointly influence helping behaviour. Although we detected kin-biased helping (demonstrating kin selection), non-kin helping was common despite opportunities to aid kin. Unexpectedly, specific pairs maintained long-term reciprocal helping relationships by swapping social roles across their lifetimes—a subtle pattern of reciprocity requiring decades of observation to detect. Given the frequency of non-kin helping and the occurrence of reciprocal helping among both kin and non-kin, helping behaviour in superb starlings seems to be greatly influenced by direct fitness. However, the relative importance of direct and indirect fitness varied with helpers’ sex and dispersal history. By uncovering a cryptic yet crucial role of long-term reciprocal helping, we suggest that reciprocity may be an underappreciated mechanism promoting the stability of cooperatively breeding societies.

DOI: 10.1038/s41586-025-08958-4

Source: https://www.nature.com/articles/s41586-025-08958-4