迷路不是人类的专利 蜜蜂也会迷路

It is not just humans that get stuck in their ways. For scientists have discovered that old bees have trouble finding their way to new hives as their learning behavior becomes increasingly inflexible.

世界上迷路的不仅仅是人类。科学家发现，“老年”蜜蜂由于行动趋于迟滞，在寻找新家时也会出现困难。

Bees are typically impressive navigators, able to wend their way home through complex landscapes after visits to flowers far removed from their nests. But researchers from Arizona State University and the Norwegian University of Life Sciences found that aging impairs the bees' ability to extinguish the memory of an unsuitable nest site even after the colony has settled in a new home.

蜜蜂一向以方向感优秀著称，它们在院里蜂窝很远的花朵上采蜜后，还能够“跋山涉水”地回到家。但是亚利桑那州里大学和挪威生命科学大学的研究人员发现，重新安家蜜蜂们会随年龄增加使得他们忘却“老家”地址的能力受到损害。

To test how old bees adapt to a changed home location, researchers trained bees to a new nest box while their former nest was closed off. Groups composed of mature and old bees were given several days in which to learn the new home location and to extinguish the bees' memory of their unusable former nest box. The scientists then disassembled the bees' new home and forced groups of mixed-age bees to choose between three alternative nest locations, including the former nest box.

为了测试出蜜蜂能在何时适应新家地址，研究者们关闭蜜蜂“老家”，并训练它们识别“新家”。有成年和老年蜜蜂的小组得到了几天识别“新家”、忘却“老家”的训练。随后科学家拆除“新家”，让不同年龄的蜜蜂们在三个“家庭住址”里选择，这里面就有它们的“老家”地址。

Old bees began flying toward the former nest site, despite the experience that should have told them that it was unusable. "Although many old bees fail in learning tasks, we also discovered that a few still perform with excellence," explains Daniel Minch, lead author of the study and a senior life sciences researcher in Norway.

“老年”蜜蜂开始飞往“老家”地址，尽管它们之前接受了识别“新家”的训练。不过该研究带头人、挪威生命科学高级研究员丹尼尔说道：“尽管许多年纪大的蜜蜂学习失败，我们还是发现其中一些表现极佳。

The scientists believe that their findings with bees offer a new means to model and understand the variability found in brain function between individuals; where some individuals' memories remain intact, while others' learning behavior becomes inflexible with age.

科学家们认为这些研究结果提供了为个体间大脑机制易变性建模及相关理解的新方法，而大脑机制易变性是指，一些个体记忆力保存完好，而另外一些个体的学习行为会随年龄变得迟滞。