There seems to be no crime too low for these penguins.

Hidden for nearly 100 years for being too "graphic," a report of "hooligan" behaviors, including sexual coercion, by Adelie penguins observed during Captain Scott's 1910 polar expedition have been uncovered and interpreted.

...

Levick noted the penguins' autoerotic tendencies, and the seemingly aberrant behavior of young unpaired males and females, including necrophilia, sexual coercion, sexual and physical abuse of chicks, non-procreative sex and homosexual behaviors.

Considered too explicit for society at the time, the pamphlet wasn't published with the other Terra Nova expedition reports. As such, it remained hidden in the bird collections at the museum to be uncovered recently by Russell.

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At the time, Levick was so shocked by what he saw he recorded the events in Greek to disguise the information, at one point writing, "There seems to be no crime too low for these penguins."