The only thing in the natural world that truly astonishes David Attenborough

Sir David Attenborough's career has spanned six decades and seen him encounter almost every animal on the planet, including pythons, orangutans and wolf spiders.

Now, he has revealed the creature he finds the most astonishing: human babies - specifically ones which are nine months old.

"The only creature that really makes my jaw sag so much that I find it hard to stop looking is a nine-month-old human baby," Sir David was quoted by the Telegraph as saying at the launch of his new show.

"The rate at which it grows. The rate at which it learns. The rate at which is acquires nerves. It is the most complex and the most extraordinary of all creatures. Nothing compares to it."

Sir David, 88, has two grown-up children. His new series Natural Curiosities begins on February 2 on Watch.

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