一枚小小的蛋，就是一个新生命的开始。卵生方式在生命演化史上具有重要意义。它的历史可以追溯到三亿多年前。全世界动物中，卵生动物占有很大比例。有些动物一年只产一枚卵。而有些动物一天内就能产数千微卵。自然界中的卵大小不同，形态各异。他们往往十分脆弱，需要小心照料。从世界上最大的鸟类。到我们花园里的昆虫。从海洋里的鱼类到生活在红范平原上的爬行动物。卵生方式让地球上偏远荒凉的角落也有可能出现成群结队的动物。生命得以世代繁衍兴盛。
Most of us come across it in some form on a daily basis: the egg. 1,200 billion eggs are consumed worldwide every year – an average of 160 per person. Chicken eggs are the most popular eggs in the world, but there is more to the egg than a balanced breakfast. Eggs are a miracle of nature, and come in all shapes, sizes and colours. Birds, fish, amphibians and insects lay eggs perfectly adapted to their respective habitat. Namibia‘s killifish inhabit one of the world‘s hottest regions. If the pools of water containing their eggs dry up, the eggs can survive for several months in the dry sand. Female herrings in the northern Atlantic lay up to 50,000 eggs, then leave their offspring to fend for themselves. The same is true of pond turtles and ladybugs, but the turtles hide the eggs in soil and ladybugs place them under leaves to protect them from the weather. Zimbabwe‘s weaver birds lay their eggs in communal nests, while the shape of common murre eggs prevents them from rolling down steep slopes. Ostrich eggs are white to reflect the sun‘s heat – but this makes them easy for hungry jackals to find. This documentary explores the wonderful world of the egg in all its different forms and reveals fascinating details about this often-overlooked natural wonder – including the fact that the chickens that lay our breakfast eggs are direct descendants of the dinosaurs!
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