Soaking up knowledge

The human sponge learns how to survive

Babies may look like wisened old men, but in their first four years they are still in a cocoon of continuous development.

First Steps, the third in BBC's 'The Human Body' series, shows how they cram huge achievements like walking, talking and being socially aware into their early years.

The most traumatic step is the 20-centimetre journey from womb to world. When the baby begins its way down the vagina it has adrenalin levels which are higher than an adult suffering a heart attack.

Inside an unborn baby's body

Open heart surgery

And its heart is doing some last-minute major surgery. An operation which would require an open-heart operation in adults is performed by the baby's own body.

The hole in its heart where it was connected to the umbilical chord is shored up by hundreds of red blood cells which rush to plug the gap.

Using hi-tech equipment, the programme shows the inside of the umbilical chord and the blood splashing through it.

Cold

A heat-seeking picture of the baby at birth shows the areas of its body which suffer most from the cold. The outside world is 15 degrees colder than the womb and it takes six months for the baby to acclimatise properly.

Presenter Robert Winston describes how babies use many strategies to survive, the most powerful of which is the ability to put a spell on their parents and wind them around their (very) little finger.

The programme follows children at four stages of early development. Baby Bob Jeffers is shown getting to grips with his muscles, breastfeeding and trying to focus.

Milk machine

The inside of the mother's milk glands are shown as the milk spurts down towards the baby. Professor Winston says the mother's body is so in tune with the baby's needs that the milk can be activated as soon as the baby cries.

Babies have some strange abilities in their first six months. For instance, they involuntarily know how to survive in water. They stop breathing and seal off their lungs so that the water goes into their stomachs. This could be a vestige of human evolution from fish or a throw-back to the womb.

Teething troubles

After six months comes pain with the growth of teeth. The tooth buds have been hidden under the gums since the baby was in the womb, but for the first time the film shows how they grow by concentrating the 40-day process into a few seconds.

The next stage of development is crawling and then walking, which Professor Winston refers to as "the real revolution", a mark of the evolution of man. At just seven months babies can sense the dangers of a slope when they are crawling and at around 11 months they get up on two feet.

The world is then their oyster, but they still have to co-ordinate their vocal chords and tongue so they can talk. Two and a half-year-old Moira learns 10 new words a day.

Toddler Moira learns the joys of dentistry

Quickly she also learns self-awareness. Unfortunately, this means she can articulate her needs and throw tantrums if she does not get what she wants.

The last stage of development is "the theory of mind". There is a wonderful sequence showing how early children learn to lie.

Around 70% of three-year-olds who are told not to peek at a new toy when an adult leaves the room do so and then lie that they have not looked. "The smartest lie," says Professor Winston.

Three triplets also show how they learn to understand what motivates other people.

70% of three-year-olds who sit the toy test lie

"This is the cornerstone of all our relationships with other people," says Professor Winston. Four-year-old Evin, James and Sean can understand fairy tales and that, just because they know the wicked witch has poisoned the apple, it doesn't mean Snow White knows.

And after all that development, the human sponges must feel the rest of life is a bit of a let-down.

The Human Body is accompanied by a £19.99 book and a CD Rom, priced £29.99.