Dr George Murray Levick was among Captain Scott's ill-fated Terra Nova expedition team to the South Pole in 1910 and was a pioneer in the study of penguins.
Levick's notes about the penguin's activities were considered so shocking at the time, that they were hidden from the official accounts.
Scientists have now found reasons behind Levick's accounts of the penguin acts, and they have now been published by the Natural History Museum.
Levick is described as shocked by what he described as the "depraved" acts of of the "hooligan" male penguins, who mated with the dead females. He also recorded the notes in Greek to hide them from the casual observer.
When Dr Levick returned to Britain, he tried to publish his paper titled 'The Natural History of the Adelie Penguin', but it was too rude for the Edwardians.
Natural History Museum curator of eggs and nests Douglas Russell told BBC News: "He submitted this extraordinary and graphic account of sexual behaviour of the adelie penguins, which the academic world of the post-Edwardian era found a little too difficult to publish."
Of the actual sex acts described by Levick, Russell explained: "What is happening there is not in any way analogous to necrophilia in the human context.
"It is the males seeing the positioning that is causing them to have a sexual reaction. They are not distinguishing between live females who are awaiting congress in the colony, and dead penguins from the previous year which just happen to be in the same position."
Two of the original 100 copies of Levick's notes survive today, with Russell only discovering one by accident.
"I just happened to be going through the file on George Murray Levick when I shifted some papers and found underneath them this extraordinary paper which was headed 'the sexual habits of the adelie penguin, not for publication' in large black type.
"It's just full of accounts of sexual coercion, sexual and physical abuse of chicks, non-procreative sex, and finishes with an account of what he considers homosexual behaviour, and it was fascinating."
Dr Levick's handwritten notes are currently on display at the Natural History Museum. Russell said that they reveal a doctor not understanding the true nature of penguins.
"He's just completely shocked. He, to a certain extent, falls into the same trap as an awful lot of people in seeing penguins as bipedal birds and seeing them as little people. They're not. They are birds and should be interpreted as such."
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