Official 19 Task 4
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Narrator: Listen to part of a lecture in a Biology class.
Professor: Today I want to talk about seabirds.
Now seabirds hunt and eat fish and, well,
their food can be hard to find because their food source is spread out over a large expanse of water.
So what seabirds have done is that over time they've made adaptations,
they've developed special characteristics that help them find food.
One adaptation involves the length of the birds' wings.
The albatross, for example,
is a large seabird that spends most of its life flying over ocean waters in search of food,
fish to feed itself and to carry back to the nest for its chicks.
Now most birds flap their wings up and down when they fly, which uses up a lot of energy.
But the albatross has these special long wings that it can hold perfectly still.
It's able to fly without moving its wings up and down.
These long wings allow it to glide or float on the wind, and this uses very little energy.
This is important because, as I said,
the albatross has to cover a huge expanse of ocean to locate food,
sometimes up to 11 hundred miles a day,
because of its long wings that can glide along over the ocean using little energy as it searches for food.
Another important adaptation of many seabirds is an acute, highly-developed sense of smell.
Take the fulmar, like the albatross,
the fulmar needs to find food that scattered far out over the ocean.
But the fulmar has a rather unusual advantage,
it has tiny tubes inside the nose holes in its beak.
And these special tube-shaped nostrils help it to pick up the scent of food.
Now this highly-developed sense of smell is especially important,
because the fulmar's main source of food, plankton, are tiny organisms that are hard to see,
but they give off a very sharp, distinctive odor.
So when fulmars are flying around looking for food, they may not be able to see them,
but they can find the plankton by smelling them, even from far away.
Question
Using the examples of the albatross and the fulmar, explain two special adaptations that have developed to help seabirds find food.