Adrian Perica is a very busy man. Over the past 18 months, the mergers and acquisitions chief at Apple has been scouring the globe looking for deals, snatching up everything from search engines and data analytics to mapping software and motion tracking chips. Such a buying spree has ignited fierce speculation in tech circles and on Wall Street about Apple’s future ambitions, especially as smartphone and tablet sales start to slow. Most of that speculation has centered on wearable technology or perhaps a souped-up upgrade of Apple TV. But Apple is thinking bigger. Much bigger. A source tells The Chronicle that Perica met with Tesla CEO Elon Musk in Cupertino last spring around the same time analysts suggested Apple acquire the electric car giant. A spokeswoman for Tesla declined to comment. Apple did not respond to a request for comment.