The history of comics has followed different paths in different cultures. Scholars have posited a pre-history as far back as the Lascaux cave paintings. By the mid-20th century, comics flourished particularly in the United States, western Europe (especially in France and Belgium), and Japan. The history of European comics is often traced to Rodolphe Töpffer's cartoon strips of the 1830s, and became popular following the success in the 1930s of strips and books such as The Adventures of Tintin. American comics emerged as a mass medium in the early 20th century with the advent of newspaper comic strips; magazine-style comic books followed in the 1930s, in which the superhero genre became prominent after Superman appeared in 1938. Histories of Japanese comics and cartooning (manga) propose origins as early as the 12th century. Modern comic strips emerged in Japan in the early 20th century, and the output of comics magazines and books rapidly expanded in the post-World War II era with the popularity of cartoonists such as Osamu Tezuka. Comics has had a lowbrow reputation for much of its history, but towards the end of the 20th century began to find greater acceptance with the public and in academia.