PLANET EARTH From Pole to Pole
Everything must be spick and span（干净整洁）. All is ready. Very impressive, but no one is watching. The superb bird of paradise calls to attract a female. And he has more luck. But what does he have to do to really impress her? She retires to consider her verdict. It's hard not to feel deflated when even your best isn't good enough.
The sun influences life in the oceans just as it does on land. Its richest parts are those where waves and currents bring fertilizing nutrients to surface waters that are bathed in sunlight. The seas off the Cape in South Africa（南非好望角） have this magic recipe and are hugely productive. Summer is the time of plenty and it's now that the seals start to breed.
The strike of a great white shark lasts a mere second. Slowing it down forty times reveals the technique and immense strength of this massive predator. If surprise fails, there will be a chase. The shark is faster on a straight course but it can't turn as sharply as the seal, its agility versus power. Once the seals have finished breeding the giant sharks will move on.
