How many letters does the top answer for “the natural history of mammalia.” have?

The most common answer is mastology (9 letters).

Crossword clue: the natural history of mammalia.

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

mastology 9 letters web-def

The natural history of Mammalia.

author of natural history 50% similar → elder

natural history philosopher 50% similar → lomonosov

wrote natural history 50% similar → elder