One of the members of the 1911 Terra Nova expedition to Antarctica, George Murray Levick, was a zoologist who made an extensive study of the Adélie penguins there. His resulting 1914 book includes several photographs of the birds in various states around their rookery, and he assigned very human characteristics to the penguins as he was studying them and stealing their eggs to eat. This was an interesting sideline book to read since it was mentioned in Cherry-Garrand’s The Worst Journey In The World, which I am finishing up now.
Postscript: apparently Levick was shocked by some of the behavior he witnessed which was excised from the book– belligerent hooligan male penguins that would have sex with each other and with dead female penguins. He encoded these notes in Greek so that only his learned pals could read them, so it wouldn’t shock the normal public supposedly.