Humans aren't the only animal to hold grudges. I know that from all the years my dog would stare down its arch-enemy through the window, the tension eventually broken by a flurry of barks. Yet even though we aren't the only ones entering into grudge matches, our species have certainly perfected the art of the feud. Like with most other things, the celebrities of Hollywood take things to another level. With the weight of public opinion in play, some of Hollywood's finest feuds not only lasted for years, but got pretty brutal in the process. 1. Vin Diesel and Dwayne Johnson While their characters in the Fast & Furious franchise eventually became allies, the two actors have had a clash of egos on set since 2016. "Any human being who knows what men are like knows to stay out [of those] situations and let them figure it out," co-star Michelle Rodriguez later said. The Rock claimed that some of his male co-stars were unprofessional and "too chicken shit to do anything about it anyway," adding that when “it seems like I'm not acting in some of these scenes and my blood is legit boiling—you're right." Then, it turned out that on the most recent entry in the series, they were never even on set with each other due to their feud. There have been times where the tension seemed to die down, only to flare up again. "It’s not always easy being an alpha," Diesel explained, "and it’s two alphas." It <a href="http://vt.co/entertainment/celebrity/dwayne-the-rock-johnson-and-vin-diesels-feud-has-reached-a-brutal-all-time-low/">didn't exactly end there</a>, however. [[instagramwidget||https://www.instagram.com/p/BZ7myLBHcyL/?hl=en]] 2. Joan Crawford and Bette Davis This legendary feud between the two actresses reportedly began in 1935, when Crawford married actor Franchot Tone. Davis apparently had a thing for Tone, who she acted opposite in the movie Dangerous - and it only escalated over the years. In 1962, only Davis was nominated for an Oscar for 'Whatever Happened to Baby Jane?', in which they both starred. So Crawford called every other nominee, offering to accept the award on their behalf if they won. When Anne Bancroft won and couldn't make the ceremony, Crawford turned up on stage to rub it in. The feud was never resolved. In fact, when Davis heard of Crawford's death, she allegedly remarked, "You should never say bad things about the dead, you should only say good. Joan Crawford is dead. Good!” 3. Tom Cruise and Brooke Shields Back in 2006, the actor called Shields' use of antidepressants for her postpartum depression "irresponsible," after she went public with her struggles. His views weren't altogether surprising given that Scientology, of which Cruise is a member, prohibits the use of any mind-altering medication, and Shields response went straight for the throat. Shields suggested that Cruise “should stick to saving the world from aliens and let women who are experiencing postpartum depression decide what treatment options are best for them". The following year the feud was resolved, Shields revealed to Jay Leno that Cruise visited her and "gave me a heartfelt apology," and she even attended his wedding to Katie Holmes that year. [[youtubewidget||https://youtu.be/tFgF1JPNR5E?t=8m10s]] 4. Rosie O'Donnell and Donald Trump Trump seems to have feuds with *checks notes* one thousand people right now, but one of the longest lasting feuds was with comedian Rosie O'Donnell. It all started in 2006 when O'Donnell criticised the now-president for not firing Miss USA in light of her drug and alcohol abuse. Trump went on to call her "a real loser," a "woman out of control," "fat," and a "pig." Once on Twitter, he came for her on every topic from her engagement to her show ratings. She hit back by mocking his numerous business failures, for which he threatened to sue. During the first presidential debate in 2016, Trump brought it up again after Clinton questioned his past misogynist remarks. “Rosie O’Donnell — I said very tough things to her," he said, "and I think everybody would agree that she deserves it and nobody feels sorry for her.” [[twitterwidget||https://twitter.com/realDonaldTrump/status/146994336670822400]] [[twitterwidget||https://twitter.com/Rosie/status/147003221943132161]] 5. Shia LaBeouf and Frankie Muniz It's unclear what started it all off, but back in 2003, LaBeouf revealed that he felt Muniz was "looking down on him," then in 2010 said, "I don't go to many parties and I don't really hang out in Frankie Muniz-type zones." Frankie then responded to say: "It's getting creepy the fact that you can't stop talking about me. It's been 12 years now. I don't know you. Thanks." [[twitterwidget||https://twitter.com/frankiemuniz/status/25986753835]] 6. Kevin Smith and Ben Affleck Former friends and colleagues in the industry Smith and Affleck apparently haven't spoken in years due to his relationship with the actor's now ex-wife Jennifer Garner: "We're not f*king tight. I have not been close with him in decades. That's old Ben. He's got a wife that don't care for me at all. "And plus, honestly, he probably don't care for me at all anymore. He's a triple-A-list movie star and s*t like that." 7. Jim Carrey and Tommy Lee Jones In an interview in 2014, Carrey revealed that his co-star on Batman Forever wasn't exactly a fan of his, as he found out when he greeted him at a restaurant: “The blood drained from his face in such a way that I realized that I had become the face of his pain or something. And he got up, kind of shaking, and hugged me and said, ‘I hate you. I really don’t like you.’ And I was like, ‘Wow, okay, what’s going on, man?’ And he said, ‘I cannot sanction your buffoonery.’” [[twitterwidget||https://twitter.com/nowthisnews/status/916070510353555456]] 8. George Clooney and David O. Russell Russell has a bit of a reputation for being a difficult director to work with, and his work with Clooney on 1999's Three Kings is no different. At one point, Russell yelled and mistreated the crew so much that the pair got into a physical fight. Producer Charles Roven recounted that George said, "I told you, motherfucker, if you're going to pick on somebody, pick on me," with the director replying, "Why don't you just fucking remember your lines for once?" In 2003, Russell charmingly stated: “George Clooney can suck my d*ck.” It just goes to show folks, even the biggest celebrities in the world can be just as petty as the rest of us - maybe even more so.

8 of the most savage feuds Hollywood has ever seen

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