Cockroaches

Cockroaches are an unlikely focus of Josef Mengele’s South American life: first creatures to be observed with painstaking attention, then props in his eccentric speculations, and finally an interest that fades as his circumstances deteriorate. The book’s account makes the insects significant not because they transform him, but because they reveal how he organizes his days, projects his fears onto the natural world, and mistakes close observation for a kind of escape.

Observation and makeshift study

In Brazil, Mengele continues to study wildlife and flora while withdrawing from ordinary company. Among the creatures that occupy him, cockroaches become a particular fixation. He calls them Blattidae and treats their bodies and behavior as subjects for sustained observation rather than as household pests. Their rapid changes of direction, which he reads about as occurring twenty-five times a second, make them difficult to catch by hand. He devises a simple lure instead, placing sugar or meat on the bathroom floor so he can watch them there.

His attention moves from movement to structure. He sketches their compound eyes and records details of their six legs, the joints in each leg, their long antennae, and the hair-covered segments that help them sense air and the presence of a predator. He is also fascinated by their ability to regrow a lost leg and by the bright, sometimes psychedelic patterns of their exoskeletons. This is meticulous looking, but not disinterested natural history: the insects’ distinctive capacities become material for his private comparisons and practical notions.

Utility and projection

Mengele’s notes about cockroaches combine observation with claims about their effects on people. He is pleased to learn that the German cockroach is considered especially harmful, carrying germs and causing allergies. At the same time, he encounters a contrasting folk remedy: powdered cockroach is said to soothe pain when applied to a wound. He imagines using the powder on a minor cut Gitta Stammer might get while preparing a salad. The proposed treatment remains an idea, not an event described as having occurred.

The insects also become a screen for his anxieties. Mengele envies them for what he takes to be their ignorance of legal proceedings and penal codes, and for their alleged ability to withstand an atomic bomb. This is less a reliable account of insect biology than a revealing projection: he turns the cockroaches’ capacity to survive and evade capture into an imagined freedom from the institutions and dangers that govern his own life. His fascination offers diversion, but does not alter his status as a fugitive or the fear that shapes his daily existence.

Routine, company, and retreat

The cockroach study belongs to a period in which Mengele struggles to adapt to a more populated Brazilian environment. He has abandoned several dogs, limits his walks to dawn and dusk, avoids the Stammers, and fills time by repairing household fixtures and building bookshelves. His study of wildlife and insects fits into this improvised routine: a private project pursued alongside solitary meals and the writing of poems in his diary. Even his idea of turning cockroach powder into a household remedy extends the fixation into domestic life, linking his private study to Gitta Stammer and the shared space from which he increasingly feels estranged.

His interest also passes, briefly, through his relationship with Wolfram Bossert. During their discussions, Bossert follows Mengele’s recommendations in literature and music and begins studying botany; he also develops a fascination with cockroaches. The episode shows Mengele taking pleasure in the influence he can exert over an admiring listener. The insects are thus not only specimens in his private world but one element of a relationship in which he presents himself as a scholar and cultivates a disciple.

Waning fascination and narrative significance

Later, after the Stammers sell their property, Mengele moves to a shabby bungalow in Eldorado. He tries to improve and secure the house but leaves projects unfinished as solitude drains his energy. In this setting the cockroaches that proliferate in the home no longer excite him. The reversal matters: creatures that had once sustained elaborate observation and speculation become part of an environment he experiences as miserable rather than intellectually absorbing. His changed response marks the narrowing of his life, not a newly acquired insight into the animals.

The motif gains force through its contrast with the book’s account of Mengele’s wartime work. At Auschwitz concentration camp, his scientific activity was bound to coercive selection and human experimentation; the insect study in Brazil offers no evidence of remorse or moral change. Instead, it shows the persistence of an ordering impulse redirected toward small, available subjects. The cockroaches have capacities and behaviors that exceed his control—speed, sensory alertness, and regeneration—yet he tries to classify, sketch, and make use of them. Their brief importance therefore illuminates both his obsessive habits and the limits of his attempted retreat: close attention to nonhuman life cannot free him from the consequences and fears of his own past.