Water - Fluid For Life (1978)

[Music] [Music] for billions and billions of years the earth was Barren and lifeless until slowly almost imperceptibly something happened [Applause] [Music] it happened in water water is and always has been the cradle for all life on Earth it is the birthplace of every living thing about 3 and A2 billion years ago life first appear appeared these are the simplest forms of life on Earth bacteria the earliest life may have looked something like this algae are another primitive form of sea life and like all green plants are producers of oxygen most of the oxygen we breathe came from plants in the sea in time plant life invaded the fresh water and as the plants flourished over the eons they continue to produce oxygen and slowly change the composition of the air and the water allowing the development of new kinds of Life oxygen breathers single celled protozoa yet even for these simple creatures the water is absolutely vital for the Water Supplies them with oxygen and [Music] food still later larger more complex organisms developed in the water creatures capable of hunting their food for water is more than the source of life it is the source of food for life [Music] a more sophisticated organism the freshwater Hydra also depends on the water for its food and survival as freshwater life evolved it also developed the ability to carry the lifegiving sea within it the fluid in the snail and in the eggs is saltwater the dragonfly nymph carries Independence one step further it begins life in water it is born there it eats and breathes in the [Music] water between a year and 5 years from its birth a wondrous transformation takes place which frees it forever from its life [Music] underwater metamorphosis [Music] [Music] the nymph changes into an air breathing dragonfly but it's link to the Sea continues the fluid in its body remains essentially sea water now it carries the sea with it up onto the [Music] land water covers 34s of the surface of our planet and it is still the home of the majority of creatures living today [Music] whether the animals are seawater or freshwater the fluid in their bodies is always basically [Music] seawater the vertebrates animals with backbones are the most advanced form of life yet are still dependent on water for their survival and reproduction [Music] most plants and animals are still conceived and born in water even you first developed in seawater for that's basically what the fluid in your mother's womb was [Music] at one stage of development you had gills and even looked like an unborn fish and though before your birth you developed into a human you share a common origin with the fish a beginning in the sea [Music] the salamander is an animal that spends part of its time on land and part in the [Music] water [Music] it's an air breather but must return to the water to Bear it [Music] young the young are left behind in the water the adult leaves the water to return to its world the land for now the young salamanders must take their oxygen from the water in time they too will take it from the [Music] air [Music] stone is the great Museum of [Music] Nature locked in the Stone are the Petrified records of earlier life in the sea by studying the structure and evolution of sea life today we are learning to reconstruct the evolution of Life long ago even today we can see fossilization going on in the water [Music] a great many plants and animals we see in the water today have barely changed over millions of years [Music] h most of our Clues to ancient sea life are not found in the water but on land that once was Beneath the [Music] Sea [Music] [Music] we learn about the past by studying the present near a fossilized crab are the Petrified remains of an ancient snail today we know of a peculiar crab that lives inside the abandoned shell of the water snail the hermit crab is probably the descendant of that earlier life form a strange lifestyle that successfully survived those millions of [Music] years it spends its life moving freely between ocean and land a versatile animal that carries its home on its [Music] [Music] back another animal from the distant past is the Scorpion today a land animal that avoids the water but the descendant of an animal that once lived exclusively in the [Music] sea the turtle is another ancient water animal but it has never completely broken its tie with the water [Music] today it spends much of its time in the water eating and mating but it must have air to breathe and it must return to land to lay its [Music] eggs water was the Cradle of all life and it still is today all living things are mainly water the support and maintainer of every life on Earth the [Music] source for