BOOK DAY: Local residents attend the Shanghai Book Fair on its August 14 opening day, where new books like the latest edition of 100,000 Whys made their debut to readers (ZHANG SUOQING)

Why are there no seeds in a banana? Why don't woodpeckers get brain damage from pecking at tree trunks at such high speeds? Why are there no animals with three legs?

The latest edition of 100,000 Whys, the most popular set of science books for Chinese children, has all the answers. Many Chinese people grew up reading this series and more than 100 million sets have been sold since 1961, when the first edition came out.

The newest set of the children's encyclopedia contains 18 volumes covering astronomy, geography, biology, zoology, botany, paleontology, brain cognition, marine environment and space programs. More than 700 hardcover copies were sold at the Shanghai Book Fair in the first two days after it hit the market on August 14, despite the hefty price of 980 yuan ($158). Printed in full color for the first time, the new edition contains more than 7,000 photos to intrigue young readers.

Seeds of science

When editors at the Juvenile & Children's Publishing House in Shanghai started their preparations for beginning the soon-to-be famous 100,000 Whys in 1959, the concept of popularizing science was almost unheard of in China. However, Chinese scientists and publishers agreed that science would be key to the nation's development and making science attractive to children in books was seen as a way to nurture the next generation of scientists. The book was named after a Russian popular science book for children published in 1929 and its translated Chinese edition was such a hit that it had been reprinted for the ninth time by 1949.

The first edition of China's 100,000 Whys answered about 1,500 questions on subjects including agriculture, animals, astronomy, meteorology, chemistry, engineering, geography, geology, mathematics and physics.

Certainly, there were never 100,000 questions in any of the six editions and each of the first five editions answered only 2,000 to 3,000 questions. The latest edition compiled 4,500 questions, selected from more than 30,000 candidates from online and offline surveys starting in 2008. More than 80 percent are brand-new, while the classical ones, like why is the sky blue, why are clouds colored and why don't the sun and moon fall down, also give new answers.

A new approach adopted by the sixth edition includes a variety of possible answers to some questions. For example, the answer to why dinosaurs disappeared contained the most common asteroid theory as well as other possible causes such as an increase in volcanic activity and a cooler climate. According to the publisher, this approach was adopted to inspire young readers' curiosity and allow them to think about and judge the theories independently.

No small questions

It has been a tradition for the publisher of 100,000 Whys to have noted scientists as consultants, who often suggested new topics and reviewed the submissions.

Top-level Chinese scientists, including Li Siguang (1889-1971), known as father of geomechanics in China, mathematician Hua Luogeng (1910-85), famous for his work on number theory, and Mao Yisheng (1896-1989), a renowned structural engineer and expert on bridge construction, were all invited to write or edit answers to questions for the second edition, which was printed in 1964 and 1965.

Around 110 top scientists from the Chinese Academy of Engineering and the Chinese Academy of Sciences (CAS) participated in the compilation of the sixth edition, more than 40 of whom personally wrote answers for some questions.

Answering children's science questions turned out to be no easy task for these top-notch scientists. They were asked to explain even the most complicated theory with the most up-to-date information and in language simple enough for a child to understand. Their mini-essays were required to be no more than two pages.

For example, Professor Huang Huan at the Department of Physics and Astronomy at the University of California, Los Angeles, wrote an essay of 600 characters summarizing three of the most up-to-date theories on the origin of water on Earth. He said that he spent a whole week writing the essay after reading dozens of papers in prestigious Chinese and foreign academic journals.