The scientific study of bird nests and nesting behavior; a specialized branch of ornithology.
From Greek 'kalos' meaning nest and 'logia' meaning study or science. The term was used in 19th and early 20th-century natural history literature but has been largely superseded by more general ornithological terminology.
Caliology is the perfect example of Victorian scientific obsession—naturalists got so specialized they created separate words for studying just nests, while modern scientists think that's hilariously narrow.
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