Making his debut in Marvel Comics in 1974, the superhero known as Wolverine has become one of the most popular and beloved superheroes of all time. His popularity grew even more when 20th Century Fox released the first X-Men (2000) and Australian actor Hugh Jackman brought the character to life and continued to do so for 17 years. However, just as with any other book-to-film adaptation, there are always things from the source material that do not make it to the screen.

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With so much source material to go over, fans of the X-Men film franchise may not know things about the mutant's life that comic-book fans do. Some of the things about him are only known to comic book fans.

He's Short In Stature

Wolverine looking fierce and angry in Marvel comics

Wolverine, aka James "Logan" Howlett, stands at 6ft 3inches tall in the movies. With Hugh Jackman's tenure as the popular Marvel superhero, that is the image most fans of the film series known him as. When in the comics, Logan does not have that same height at all, where he only stands at 5ft 3inches tall.

His height is often the punch line of jokes in the series; in Savage Wolverine #2 (2013), they even have another character named Shanna who jokes that she thought he'd be taller like that actor Hugh Jackman.

He Fought In World War II With Captain America

Wolverine and Captain America attacking at the same time in Marvel Comics

Movie fans know that Wolverine, over his long life, has fought in several wars during the centuries, which was gone over in X-Men Origins: Wolverine (2009).

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However, only comic-book fans may know that during WWII, Wolverine served as part of the Canadian Air Force and fought alongside another widely popular Marvel superhero, Captain America. The two teamed together on several occasions during the war.

He Has A Son

Wolverine-fighting-his-son-Daken in Marvel Comics

In 2017's Logan, fans of the film franchise were introduced to Laura Kinney, aka X23, a superhero clone. They see Logan grow from a man who just took the job for the money into a father figure for the girl during the film. In the comics, however, fans have known Wolverine as a father for years both as a mentor to many mutants at Xavier's school and as a father in his own right, to Daken.

Daken, also known as Akihiro, was the son of Wolverine and his wife Itsu in 1946. Sadly, Itsu was murdered by the Winter Soldier while pregnant with Akihiro to attempt to draw out Wolverine to return him to Madripoor. Another character by the name of Romulus cuts Daken out of his mother, and due to his healing powers, he survived. Logan's relationship with Daken has always been rocky at best, and sadly, Logan ended up having to kill his own son.

He Has A Fear Of Water

Wolverine drowning in water.

As long as Logan has lived during the years, one would not expect him to have too many phobias; however, Wolverine actually does have one fear, and that is water. Wolverine actually has an excellent reason not to want to be heading out to the lake on the weekends, and that's because drowning is one of the few things that can actually kill the superhero.

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The reason it can drown him comes down to his adamantium-lined skeleton will make him drop like a rock in any body of water. Not only does he sink but his healing powers also do not work when submerged, leaving him just as vulnerable as any human under the water.

Not Just An X-Men

X-Force with Warpath, Wolverine and X-23

In the films, the audience has only ever seen Wolverine as a member of the X-Men team in the comics; however, Logan has served on over ten different superhero teams, including the Avengers, the Fantastic Four, and X-Force. Those three only touch the surface of the teams that Wolverine has worked on.

It makes sense that he'd have such an impressive resume, considering how long he has been around. Wolverine, however, always comes back to the X-Men, so it makes sense that the film franchise would focus on the home team.

Logan's Sexuality

Wolverine and Hercules kiss in Marvel Comics.

While Logan's sexuality has never been confirmed within the main timeline, there's enough to make comic-book fans speculate that Logan may actually be bisexual. There was an issue with a Wolverine from a different reality that had a relationship with Hercules, sharing a kiss in an iconic pannel.

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While they've never confirmed his sexual identity, recently, there was a panel where he was sharing a rather intimate embrace with Cyclops and Jean Grey, making fans speculate further that he's bisexual.

Wolverine Trained The Black Widow

Black Widow talking with Wolverine about training in Marvel comics

During the 1940s, Wolverine trained Natasha Romanoff, who fans know as Black Widow. In the comics, Black Widow receives the Red Room equivalent to the Super Soldier serum, giving her the same longevity that Steve Rogers had.

The two heroes met, and both of them with similar pasts cared greatly for one another. Wolverine trained the young Russian spy until Baron Strucker kidnaped her. They have maintained a deep friendship, Natasha even frequently calling Logan  her "little uncle."

Xavier Brainwashed Logan

Professor Charles Xavier in his chair in Marvel Comics

The storyline used in the movies is that the Weapon X program wiped Logan's memory and turned him into a weapon. In the comics, there is another alarming storyline that may alarm movie fans, that Professor Xavier once was the one who actually wiped Logan's mind. In X-Men Origins #29, the Weapon X program had sent Wolverine to assassinate the professor. Xavier read his mind and saw what he was there to do.

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Xavier took certain memories from Logan using his powers and implanted others to manipulate the Wolverine into becoming an X-Men member. Movie fans may not know this about the professor who has a history of making some questionable decisions regarding his team.

Wolverine Cannot Get Drunk

Wolverine roaring in rage in Marvel Comics

In both the comics and the films, it's a well-known fact that Wolverine is a fan of alcohol. What film fans may not know is that alcohol doesn't affect Logan like it does others due to his healing factor.

Film fans may recognize this as a similar issue that Captain America has in Captain America: The First Avenger. So while Logan is known for drinking his beer and whiskey, he could drink all day and not be phased by its negative effects.

Wolverine Debuted As A Villain

Wolverine fighting The Hulk in his first appearence in Marvel Comics

It may surprise some film fans, but the Wolverine wasn't always a superhero. In fact, in the comics, Wolverine made his debut in The Incredible Hulk #181 in 1974. The Hulk is fighting in the forest against the Wendigo, and Wolverine comes out of nowhere and starts to attack the Hulk.

When Wolverine discovers his claws won't pierce his skin, he turns to the Wendigo and starts to attack him. Both the Hulk and Wolverine end up teaming up together to take down the beast. But comic-book fans know that his status as a villain was short-lived.

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