Recent research revealed rich socio-cognitive abilities in toddlerhood. The current study investigates whether 21-month-olds expect that wealthy agents help agents needing food or shelter. By using the violation of expectation (VoE) implicit paradigm, toddlers' expectations on helping behaviors were explored upon the arrival of agents that need food (food condition) and shelter (shelter condition) in a within-subjects design. Two experiments were carried out, wherein, in one, the wealthy and needy agents were morphologically similar (Experiment 1), in the other one, the wealthy agents were morphologically different from needy agents (Experiment 2). The results showed that when needy agents are morphologically similar to wealthy agents, toddlers looked longer at the event that displayed the wealthy agents help needy agents only in food condition. When needy agents were morphologically different from wealthy agents, toddlers looked longer at the event that showed wealthy agents help needy agents in both food and shelter conditions. These findings demonstrate an interplay between similarity and helping behaviors in association with biological needs, and shed light on possible evolutionary mechanisms underlying prosociality.

中文翻译：

---

蹒跚学步的孩子更喜欢代理人帮助类似或不同的有需要的代理人吗？

最近的研究揭示了幼儿时期丰富的社会认知能力。当前的研究调查了 21 个月大的孩子是否期望富有的代理人帮助需要食物或住所的代理人。通过使用违反期望 (VoE) 隐式范式，在被试内设计中，在需要食物（食物条件）和住所（庇护条件）的代理到来时，探索了幼儿对帮助行为的期望。进行了两个实验，其中一个，富人和贫困者在形态上相似（实验1），在另一个实验中，富人与贫困者在形态上不同（实验2）。结果表明，当有需要的代理人在形态上与富有的代理人相似时，蹒跚学步的孩子更长时间地观看事件，该事件显示富有的代理人只在食物条件下帮助有需要的代理人。当有需要的代理人在形态上不同于富有的代理人时，蹒跚学步的孩子会更长时间地看到富有的代理人在食物和住所条件下帮助有需要的代理人的事件。这些发现证明了相似性和与生物学需求相关的帮助行为之间的相互作用，并阐明了亲社会性背后可能的进化机制。