热带蜜蜂夜间飞行毫不费力(上)

This is Scientific American’s 60 -Second Science. I’m Karen Hopkin.

这里是科学美国人——60秒科学系列，我是凯伦·霍普金。

They say it’s darkest before the dawn. And that’s just the way that sweat bees like it.

都说黎明前最黑暗。这正是汗蜂喜欢的方式。

These tropical insects, which live on an island in the middle of the Panama Canal, visit night-blooming flowers under cover of darkness.

这些热带昆虫生活在巴拿马运河中部的一个岛屿上，在夜幕的掩护下，它们降落在夜晚盛开的朵朵花儿上。

And a new study shows that the shapes made by gaps in the rainforest canopy help them find their way home.

一项新的研究表明，雨林树冠缝隙形成的形状有助于汗蜂找到归家之路。

The work appears in the journal Current Biology.

这项研究发表在《当代生物学》杂志上。

Even though most bees are active in bright daylight, there are a few species that have become nocturnal due to competition and due to predators.

尽管大多数蜜蜂都在明亮的白天活动，但由于竞争和捕食者的存在，也有少数蜜蜂变成夜行性动物。

Eric Warrant, a professor of zoology at the University of Lund in Sweden.

艾瑞克·沃瑞特是瑞典隆德大学的动物学教授。

This is particularly true of the warmer parts of the world, such as the steamy rainforests of Panama.

在世界上较温暖的地区，比如巴拿马闷热潮湿的热带雨林， 尤为如此。

Warrant and his colleagues have been studying these night flyers, called Megalopta genalis, for more than 20 years.

沃瑞特和他的同事已经研究这些夜间飞行的蜜蜂二十多年了，这些蜜蜂被称为夜行隧蜂(Megalopta genalis)。

We have discovered that, like all bees, Megalopta is able to learn visual landmarks around the nest and presumably also along the foraging route.

我们发现，与所有的蜜蜂一样，隧蜂能够获悉巢穴周围的视觉地标，觅食路线大概也能记住。

They use these landmarks to find their way through the vast forest and to recognize their nests.

它们利用这些地标在广袤的森林里寻路、识别蜂巢。

No easy feat, especially considering the size of these nocturnal navigators.

这并非易事，尤其是考虑到这些夜间导航者的体型。

Exactly how they manage to do this with such tiny eyes and with such a small brain is still to a large extent a mystery.

它们是如何用这么小的眼睛和这么小的大脑在夜间进行导航的，在很大程度上，这仍然是个谜。

But it seemed that the first step would be to simply look up.

但第一步似乎只是简单地抬头看。

There is one visual cue that is quite obvious in this otherwise profoundly dim environment.

在这个昏暗无比的环境中，有一个视觉线索非常明显。

And these are the bright patches of night sky seen through gaps in the forest canopy directly above.

这个线索就是从正上方森林树冠的缝隙中看到的夜空下的亮斑。