國(guó)家地理:Halloween: Giant Bats 巨型蝙蝠

As the sun goes down every evening in northern Australia, millions of dark, huge, winged creatures dominate the skies.
They're an imposing sight, but these black flying foxes are just big harmless bats, the biggest in the world.
Their wingspan can reach a whopping six feet. Given that the world's smallest bat species weighs less than a penny, that's pretty big.
Nearly one quarter of the world's mammal species are bats. 160 of these are fruit bats and 60 of these are called flying foxes, for their unique looking, fox-like faces.
The black flying fox babies can't fly for the first month, which means the moms have to carry them, even when they become airborne.
At night, they search for fruit and nectar, mainly through sight and smell. Like other fruit bats and vampire bats, black flying foxes don't rely on echolocation. During the day, they live in huge colonies or camps housing up to 100,000 flying foxes. Usually they stay relatively cool by roosting in mangrove and paperbark trees that sit in water. But sometimes even this location isn't cool enough. Ever wore a black fur coat in the intense Australian heat? You can imagine why they fan themselves.
Hey, when that doesn't work, they'll lick themselves. They cool down a little as their saliva evaporates. But with 100,000 bats in the same grove of trees, things are bound to heat up.
Fights often break out over which branch belongs to whom. They defend their turf. But they rarely break skin. Mostly it's just a lot of noisy posturing. Posturing aside, this big black flying creature is nothing more than a fuzzy foxy looking vegetarian.
New Words:
roost: (v.) To rest or sleep on or as if on a perch or roost. 棲息
mangrove: (n.) [植]紅樹(shù)林
paperbark: (n.) (澳大利亞的)白千層屬植物
saliva: (n.) 唾液