From early buddhist sutras like the dhammapada to later, more elaborated phiolosophical texts like nagarjuna's Mūla-madhyamaka-kārikā verse is very often used in buddhist text. Whats the reason for this?Have any authors written explaining why they write in verse instead of prose? I can immagine oral transmission and ritual recitation as the reason for certain sutras being in verse, but what about more analytical works?
You are correct in your assumption that the verse, and in some cases, prose, were composed with memorisation in mind.
At the time of the Buddha, the only local example of a preserved religious teaching was the Vedic literature as kept by the Brahmin, but this required extensive education that did not exist for early Buddhists, who initially were converts, rather than Buddhists from birth. (Brahmin, like the other castes, were ascribed to their caste at birth and raised accordingly) The Sangha (Buddhist monastic order-monks, nuns, novices) were established to help people attain nirvana as well as to preserve the teachings of Buddha, and initially, at least, the way to do this was to use versification, mnemonics, lists and other memorisation techniques. Later, when the sangha had spread and education structures were established, the material was left largely unchanged, so as to preserve the essential wisdom that may otherwise have been compromised.
Reference - Buddhism: Critical Concepts in Religious Studies (vol 1). Paul Williams (ed.), 2005