"So, every sentence in our scripts is carefully crafted, down to the punctuation."

Even though he'd made it big online, Zhang has remained committed to writing popular-science books.

He believes that although new media can reach a wide range of audiences very quickly, books truly preserve knowledge long term and leave their mark on the world.

Last year, Zhang published the fourth volume of Notes of Hai Cuo Tu, which was inspired by Hai Cuo Tu, a work on marine life that dates back three centuries and features drawings by Chinese artist, painter and biologist Nie Huang during the Qing Dynasty (1644-1911).

Hai Cuo Tu documents more than 300 species of marine life in vivid writing and paintings.

Although the book contains some inaccuracies, it's still valuable for gaining a modern understanding of the historical marine environment, Zhang says.

Zhang took up Nie's unfinished cause in 2014, dedicating himself to this research and unraveling the mysteries of various marine creatures.

In the latest volume, he focuses on 96 original illustrations from Hai Cuo Tu and delivers identification and detailed introductions of fish, mollusks, mammals and marine plants.

Liu Shujuan, who edited Notes of Hai Cuo Tu, comments that Zhang appeals to young readers through providing a good balance of scientific expertise, and interesting and thought-provoking writing.

"Zhang has brought natural history out of the ivory tower," Liu says.

Zhang hopes that he can use videos to arouse people's initial interest and subsequently invite them to read his books.

"That's how I intend to do it now," he says.

Recently, Zhang's plan to film deserts in the Xinjiang Uygur autonomous region, creatures in karst caves in the Guangxi Zhuang autonomous region and rainforests in Malaysia won Bilibili's best proposal award.

"It's scheduled for public release at the end of the year," he says.

Zhang's online alias conveys his belief that a person can shine even if they're limited.

And he hopes to use the light of his individual life to more brightly illuminate the public's understanding and appreciation of science and nature.

Contact the writer at yangfeiyue@chinadaily.com.cn