BioEd Online

Near the town of Nanyuki

No Grickle-grass grows

And the wind smells fast and sweet when it blows.

Nevertheless some scholars propose

That this is the home of the Lorax.

Of the dozens of children’s books Theodor Seuss Geisel wrote under his pen name — Dr Seuss — The Lorax was reportedly his favourite. Published in 1971, it tells the story of deforestation and environmental destruction by the Once-ler and his family, despite the protestations of “sort of a man” — the curious Lorax.

Most readers have assumed that the Lorax was a character born in Geisel’s extraordinary mind. But a study published in Nature Ecology & Evolution on 23 July suggests that Geisel was inspired by a monkey that lives across West and East Africa.

“It began at a formal dinner,” says Nathaniel Dominy, an anthropologist and evolutionary biologist at Dartmouth College in Hanover, New Hampshire, where Geisel once studied. Dominy was seated beside Donald Pease, the Ted and Helen Geisel Third Century Professor in the Humanities at Dartmouth. “I have two young kids, and because he’s the Geisel professor, I figured Dr Seuss was some common ground,” says Dominy.

He told Pease that during fieldwork in Kenya, he had often thought that the patas monkey (Erythrocebus patas) looks as if it walked off the page of a Dr Seuss book.

Then Pease surprised him: Geisel, he said, had visited Kenya in 1970. The author and his wife stayed at the exclusive Mount Kenya Safari Club in Nanyuki — and it was there that Geisel wrote about 90% of The Lorax. As Dominy and Pease talked, an idea began to emerge: had the patas monkey been an inspiration for the book’s main character?

Familiar face

The more the researchers discussed the idea, the more plausible it seemed. Dominy explained that the patas monkey is highly dependent on the whistling thorn acacia tree for food. Could this explain why the Lorax, who “speaks for the trees”, is so keen to protect them?

Dominy and Pease enlisted the help of James Higham, an anthropologist at New York University who had developed software to analyse facial similarities among 22 species of closely related monkey, including the patas monkey. The researchers added the face of the Lorax to the database, along with a control: the face of a Dr Seuss character from a book published a couple of years before Geisel’s visit to Kenya. When they ran Higham’s software, it classified the face of the Lorax as either a blue monkey (Cercopithecus mitis) or as a patas monkey.

“It was such a great moment when we got those results,” says Dominy. The software placed particular importance on the distinctive facial hair around the mouth of both the Lorax and the patas monkey. But Dominy says there are similarities between the two that aren’t picked up in a facial analysis. Posture is one: the patas monkey spends a lot of its time on two legs to reach fruit, and the Lorax stands upright.

Sketching possibilities

Pease cautions that the results don’t imply that the Lorax is a patas monkey. “But just as a domestic cat can be seen to bear a resemblance to the Cat in the Hat, this figure of the monkey bears a sufficient resemblance to the Lorax to function as a possible inspiration,” he says.

“I love it,” says Nathalie op de Beeck, an associate professor of English and director of children’s literature and culture at Pacific Lutheran University in Tacoma, Washington. “This is such a beguiling way to think about what Theodor Geisel or anybody would have experienced in that area of Kenya in the early 1970s. I can imagine so many of his other animal sketches coming out of species he saw on that trip.”

The experimental approach is a reasonable way to determine the facial similarities between the fictional Lorax and real-world monkey species, says Anil Jain, a computer scientist at Michigan State University in East Lansing who has developed primate facial-recognition software. But he notes that the paper does not provide numerical data on the degree of similarity between the Lorax and the various real-world monkeys, which would give readers a better sense for the strength of the character's resemblance to the patas monkey.

Helen Kopnina, a conservation anthropologist at the Hague University of Applied Sciences in the Netherlands, dislikes the philosophical consequences of seeing the Lorax as a monkey

“I didn’t like the article,” she says. The study’s authors argue that the Lorax claims to “speak for the trees” because as a monkey, he is a sustainable consumer of the trees’ fruit. Kopnina rejects this. “The argument that he is a monkey weakens his authority,” she says. “Because then he becomes just a self-interested consumer, struggling to keep things for himself.”

Disappearing act

What is beyond doubt is that patas monkeys are heavy consumers of the whistling thorn acacia tree. “The gum of [the tree] is a staple part of their diet,” says Lynne Isbell, a behavioural ecologist at the University of California, Davis. Just as in The Lorax, those trees are now disappearing, felled to clear land and to make charcoal.

“We have a situation where patas monkeys are now not seen as often as they used to be,” says Isbell. “They were always uncommon, but now they’re gone from places where I used to see them occasionally even just 20 years ago.”

The Lorax ends with a message of hope — that environmental degradation can be reversed and ecosystems restored. “It would be great if this work raises visibility for this animal and the ecosystem,” says Dominy. “If people are more conscious about it, that could encourage more conservation.”