The Life Collection
The Sky Above (2x7)
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This episode deals with the air and those creatures that spend most of their lives in it. Attenborough begins in NASA’s gravity research aircraft to illustrate the effect of weightlessness. There are surprisingly many plants whose seeds are, in effect, lighter than air. Gossamer is the animal equivalent, spun by tiny spiders. Only the very smallest plants and animals can defy gravity, but some seeds, such as those of the sycamore, cheat this by simulating the movement of a helicopter. Many creatures are expert gliders, such as the flying frog and some species of lizard. However, those that live at grass level must use powered flight, sometimes aided with a leap, as with the grasshopper. Attenborough observes albatrosses in South Georgia exploiting the air currents above cliffs to glide all day. Heavy birds like vultures wait for the land to heat up and provide thermals before they attempt any lengthy flight. The techniques of diving birds, such as the gannet or the peregrine falcon, are shown. Migratory birds are also explored in detail, and a multitude assembles above Panama each autumn. The red-breasted goose migrates entirely overland, and so can stop for fuel every night — unlike those that cross the open ocean. Finally, Attenborough ascends 6.5 kilometres into the atmosphere in a hot air balloon. It is this space that contains the Earth’s weather, and satellite imagery is used to illustrate the formation of hurricanes and tornados.