In Tove Jansson’s tenth Moomin comic, Moomin Valley Turns Jungle, a heatwave threatens to cause disaster in Moominvalley. Little My finds a box of exotic seeds in the sea, which Moominmamma plants in the garden at Moominpappa’s request. The seeds grow rapidly, and Moominvalley is transformed into a jungle. The mischievous Sniff complicates the situation further by releasing all the animals from the zoo.

Moominpappa makes the best of the situation and starts reading Tarzan while wearing a sun hat. Moomintroll also starts playing Tarzan. Tarzan was Tove Jansson’s favourite hero as well, during her childhood. She recalls this in her essay Tarzan den Oförlikneliga (Tarzan the Incomparable): “It was only when I discovered Tarzan, the boy, that adventure leapt straight out of the book and captivated me irresistibly and dramatically… Despite all my beloved books, however admirable and meaningful they were, I believe that Tarzan was the most important, because he gave me my own jungle and, for the first time, the intoxicating feeling of daring and being stronger.”

Hemulen, the Botanist, and Hemulen, the Zoologist, also arrive in the new jungle in Moominvalley, where they argue in their usual serious hemulen manner.

Moomin Valley Turns Jungle contains amusing little references to reality. At the end of the story, Snorkmaiden gives Moomintroll a marmoset. In reality, Tove Jansson’s father, Viktor ‘Faffan’ Jansson, had a marmoset named Poppolino in their artist’s home in Lallukka.

A zookeeper claims the Moomins are hippopotamuses and tries to force them into the zoo, but Hemulen, the Zoologist, convinces him they are not. In 1955, a hippopotamus was born at Whipsnade Zoo in England, and there were plans to name it Moomintroll. However, this did not happen because the hippopotamus sadly died. Six months later, in the autumn of 1955, a hippopotamus calf was expected at London Zoo, which they also wanted to name Moomintroll, but the mother had a miscarriage, and the calf was never born. 

It is also interesting to look at the series Moomin Valley Turns Jungle and see the difference Tove Jansson makes when she uses halftones and small lines to create shadows in the story. 

Moomin Valley Turns Jungle was published in 1956. The Finnish name is Viidakkoelämää, and the Swedish name is Vi bor i en djungel.