Gagliardo A, Ioalè P, Odetti F, Bingman V P
Dipartimento di Etologia, Ecologia ed Evoluzione, Università di Pisa, Italy.
Proc Biol Sci. 2001 Jan 22;268(1463):197-202. doi: 10.1098/rspb.2000.1350.
Homing pigeons can learn a navigational map by relying on the heterogeneous distribution of atmospheric odours in the environment. To test whether there might be a sensitive period for learning an olfactory-based navigational map, we maintained a group of young pigeons in an aviary screened from the winds until the age of three to four months post-fledging. Subsequently, the screens were removed and the pigeons were exposed to the winds and the environmental odours they carry for three months. One control group of pigeons was held in a similar aviary but exposed to the winds immediately upon Hedging, while another control group of pigeons was allowed free-flight. When the pigeons from the three groups were released from two distant release sites at about six months of age post-fledging, the two control groups were found to be equally good at orientating and returning home, while the experimental pigeons held in the shielded aviary for the first three months post-fledging were unable to orientate homeward and they were generally unsuccessful in returning home. This result supports the hypothesis that environmental experience during the first three months post-fledging is critical for some aspect of navigational map learning and that navigational map learning displays sensitive period-like properties.
家鸽可以通过依赖环境中大气气味的不均匀分布来学习导航地图。为了测试学习基于嗅觉的导航地图是否可能存在一个敏感期，我们将一群幼鸽饲养在一个避风的鸟舍中，直到它们离巢后三到四个月大。随后，移除屏风，让鸽子暴露在风中以及风中携带的环境气味中三个月。一组对照鸽子饲养在类似的鸟舍中，但在离巢后立即暴露在风中，而另一组对照鸽子则允许自由飞行。当这三组鸽子在离巢后大约六个月大时从两个遥远的放飞地点放飞时，发现两个对照组在定向和返家方面同样出色，而在离巢后的前三个月饲养在屏蔽鸟舍中的实验鸽子无法向家的方向定向，并且它们通常无法成功返家。这一结果支持了这样的假设，即离巢后前三个月的环境体验对于导航地图学习的某些方面至关重要，并且导航地图学习表现出类似敏感期的特性。
