Oscarsson Rebecca, Gjøen Johanna, Jensen Per
IFM Biology, AVIAN Behaviour Genomics and Physiology Group, Linköping University, Linköping 581 83, Sweden.
Biol Lett. 2025 Feb;21(2):20240607. doi: 10.1098/rsbl.2024.0607. Epub 2025 Feb 5.
The phenotypic alterations brought by domestication have been hypothesized to be driven by selection for tameness. To explore this, we selected red junglefowl (RJF) for high (HF) and low (LF) fear of humans for 14 generations. We previously found that domesticated chickens performed more play-like behaviours during early ontogeny, and therefore, in this study, we explored potential effects of tameness. Groups of three to four chicks were randomly created from each selection line, and each group was moved to an enriched play arena twice per week, from day 6 until day 53 post-hatch. The frequency of 14 different play-like behaviours, categorized as locomotor, social and object play-like behaviour were recorded for 30 min at every observation instance. Every group of three or four birds constituted the independent statistical replicates and measures were averaged within the groups. The frequency of total play-like behaviour as well as object, and locomotor play-like behaviour was significantly higher in LF, while social play-like behaviour was significantly more common in HF. This largely mirrors previous observations of differences between domesticated and ancestral chickens. Hence, our results support the important role of tameness for the evolution of domesticated behaviour.
驯化所带来的表型改变被认为是由对温顺性的选择驱动的。为了探究这一点，我们对红原鸡（RJF）进行了14代的选育，分为对人类高恐惧（HF）和低恐惧（LF）两组。我们之前发现，驯化的鸡在个体发育早期表现出更多类似玩耍的行为，因此，在本研究中，我们探究了温顺性的潜在影响。从每个选育系中随机挑选三到四只雏鸡组成一组，从孵化后第6天到第53天，每组雏鸡每周两次被转移到一个丰富的玩耍场地。在每次观察时，记录30分钟内14种不同的类似玩耍行为的频率，这些行为分为运动性、社会性和物体类类似玩耍行为。每三到四只鸟组成一组作为独立的统计重复样本，测量结果在组内进行平均。LF组中总的类似玩耍行为以及物体类和运动性类似玩耍行为的频率显著更高，而HF组中社会性类似玩耍行为显著更常见。这在很大程度上反映了之前对驯化鸡和原始鸡之间差异的观察结果。因此，我们的结果支持了温顺性在驯化行为进化中的重要作用。
