David Duchovny refuses to go commando when he wears a kilt

He told The Guardian: "My mother was Scottish. I've worn a tartan that I'm supposedly allowed to wear through her background.

"I'm not just throwing on a kilt willy-nilly. I'm respecting the tradition. I do enjoy wearing them.

"They're a comfortable article of clothing. No underpants? When that tradition was founded, there was no Internet.

"I prefer to wear underpants and not have a stupid viral moment."

David was born in New York City to father Amram 'Ami' Ducovny, a writer and publicist who worked for the American Jewish Committee, and Margaret 'Meg' Miller, who worked as a school administrator and teacher.

Along with his Scottish ancestry, David said animals and deep thoughts about the planet are the main thing that pique his curiosity.

He said when asked to detail his interests: "Not food. I'm just not that guy. Animals always spark my curiosity.

"I have one dog right now. The water, the ocean, humanity, what we're doing on the planet, these kinds of things.

"Big questions and small."

David - who shot to global fame playing Special Agent Fox Mulder on sci-fi series 'The X-Files' - dismissed the rumour he was struggling before he landed the job.

He said when asked if he was "completely broke and willing to give up acting" when the offer for the part turned up: "No. I was pretty broke all along. I wasn't raised with money. I was doing odd jobs, catering, bartending.

"I did a few commercials. I'd acted in four or five movies and also 'Twin Peaks'. I wasn't rolling in dough, but I wasn't broke."