One Direction recently discussed the more mature sound of their latest album, "Midnight Memories," in an interview with Telenoche while bandmate Niall Horan ironically couldn't resist showing off his armpit hair, as Unreality TV reports.

After being asked to describe the "evolution of the band," Liam Payne responded, "Well, I think it's a lot more live sounding. There's a lot more maturity in it, and I think the main difference is that we wrote this one, really. We wrote a few tracks on each of the albums but on this one, we spent a lot of time on it."

Added Harry Styles, "If you listen to the first album, then listen straight to the third album, it's completely different. Even though it's only been three years [since 1D were formed] I think when you're our age, three years is a long time and quite a lot has happened in terms of growing up in those three years."

Meanwhile, Horan jokingly showed off the armpit hair he's been growing over the past three years, while Payne pointed out the small but noticeable beard he's managed to grow, as proof of the boys' "maturity," of course.

The bandmates did indeed contribute a great deal of the writing on "Midnight Memories," making it perhaps their most personal album yet, a departure from their far more pop-sounding first two efforts, "Up All Night" and "Take Me Home." Louis Tomlinson wrote on most of the tracks, including the album's title track and the band's latest single.

"Midnight Memories" has received mostly positive responses from critics, though some have lamented the loss of the band's signature catchy sound that made their first two albums so memorable.