Complex sentence: Buffon was instrumental in transforming the Jardin du Roi into a major research center and museum; he also enlarged it, arranging the purchase of adjoining plots of land and acquiring new botanical and zoological specimens from all over the world.
Split into simpler sentences: Buffon was instrumental in transforming the Jardin du Roi into a major research center and museum. He also enlarged it, arranging the purchase of adjoining plots of land and acquiring new botanical and zoological specimens from all over the world.