Title sub-sections for a \documentclass{article} [duplicate]

How can I specify a specify a "sub-title" in my title (\maketitle) page? By sub-title I mean something like a hierarchical child of a title, think "relationship between \section and \subsection", obviously smaller in font size but still looking as part of the title (e.g. "Bananas in the Savanna" "Cropping crap changes the genome of the biome"). Crap = natural fertiliser.

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