How many letters does the top answer for “the sexual reproduction of animals.” have?

The most common answer is zooegamy (8 letters).

Crossword clue: the sexual reproduction of animals.

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

zooegamy 8 letters web-def

The sexual reproduction of animals.

zoogamy 7 letters web-def

The sexual reproduction of animals.

a sexual attraction to animals 50% similar → zoophilia, zoophilism