Penguins have about the most fuzzy, cute and innocent reputation in the animal kingdom, enough to inspire animated movies where they tap dance and sing.
A polar explorer in 1910, however, beheld behavior among the Adelie penguins in Antarctica that shocked his gentlemanly sensibilities.
The Natural History Museum of London released manuscripts written by Dr. George Murray Levick, a medical doctor who accompanied Captain Robert Scott on an ill-fated expedition to the continent which lasted from 1910 to 1913, during which he observed the behavior of a colony of penguins, according to The Telegraph.
The behavior that particularly horrified an "Edwardian Englishman" like Levick was the sight of a young male Adelie penguin trying to mate with a dead female, according to the Guardian.
Levick spent the entire Antarctic summer of 1911 to 1912 observing the colony at Cape Adare, the only scientist to this day to study an entire breeding cycle, said the Guardian.
He wrote: "I saw a cock engaged in the sexual act upon the dead body of a white-throated Adelie of the previous year. This took somewhat over a minute, the position taken up by the cock differing in no way from that of normal copulation," according to The Telegraph.
He was so shocked by what he called the "depraved" behavior of "hooligan" males who mated with dead females, that he recorded the observations in Greek in his notebook, according to the BBC.
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Douglas Russell, the curator of eggs and nests at the Natural History Museum, clarified that the young male penguins were just too inexperienced to differentiate between willing and live females and dead females that happened to be in the same position.
When Levick tried to publish the "natural history" of the Adelie penguin, it proved to be too much for the era. Russell told the BBC, "He submitted this extraordinary and graphic account of sexual behavior of the Adelie penguins, which the academic world of the post-Edwardian era found a little too difficult to publish."
The graphic section on the penguins' sexual activities was removed from "Natural History of the Adelie Penguin" and later used to create a short paper circulated only among a small circle of experts.
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"The pamphlet, declined for publication with the official Scott expedition reports, commented on the frequency of sexual activity, auto-erotic behavior, and seemingly aberrant behavior of young unpaired males and females, including necrophilia, sexual coercion, sexual and physical abuse of chicks and homosexual behavior," said the analysis written by Russell and colleagues William Sladen and David Ainley, according to the Guardian.
In addition to the necrophilia, Levick also witnessed males pleasuring themselves, males having sex with other males, and coercing females and chicks and sometimes killing them, said the Guardian.
After having his delicate sensibilities shocked, Levick had to spend another Antarctic winter stranded with the team, surviving on blubber, because ice blocked the ship that was meant to pick them up.