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It's like dog years — but not

Avengers: Infinity War type Movie

Even though "Adolescent Groot" doesn't have the same adorable ring to it as "Baby Groot," Guardians of the Galaxy writer-director James Gunn says the character is just that — "not a ‘teen'" — in the new Avengers: Infinity War footage that screened last weekend at D23 and again Saturday at Marvel's Comic-Con panel.

In a Facebook post Sunday, Gunn attempted to explain Groot's growth and the alien biology of it all.

"People are asking me a lot about how fast Groot grows, because in his appearance in the Infinity War trailer he was an ADOLESCENT (not a "teen" as has been reported in many places)," Gunn wrote, after providing a ***SPOILER ALERT*** — as are we. "This is exactly the same state of growth you see in the post credits scene of Vol. 2: Adolescent Groot."

Baby Groot of Guardians 2 is two months older than what we saw at the end of the first movie, Gunn said; the Vol. 2 post-credits scene with Adolescent Groot and Peter Quill (Chris Pratt) is "YEARS after" the ending of that movie. "I won't say exactly how many years at this time, but be clear that it took him a fair amount of time just to go from Baby Groot to Adolescent Groot," the filmmaker said. As a side note, he added, "I'll point out that Peter Quill can obviously understand what ‘I am Groot' means in the post-credits scene, so somehow he's learned to understand him in the same way Rocket has."

Gunn continued: "Like dogs, who grow at a different rate than humans, and spend a different percentage of their lives in adolescence than humans do, Groot and Humans do not grow at some exact exchange rate. So, although two months seems to be about two years (as Baby Groot seems to behave roughly like a two year old), it is not fair to assume that every month is a year to Groot. He has an alien biology and ages in a completely different way than a human being. Different aspects of his growth may take longer or shorter than a human's."

See Gunn's full Facebook post below. <iframe src="https://www.facebook.com/plugins/post.php?href=https%3A%2F%2Fwww.facebook.com%2Fjgunn%2Fposts%2F10154433825566157&width=500" width="500" height="306" frameborder="0" scrolling="no" class="" allowfullscreen="" resize="0" replace_attributes="1" name=""></iframe>

For more on what happens in that Avengers: Infinity War footage, which has not yet been publicly released, click here. The movie — starring Robert Downey Jr. (Tony Stark/Iron Man), Chris Evans (Steve Rogers/Captain America), Chris Hemsworth (Thor), Scarlett Johansson (Black Widow), Mark Ruffalo (Bruce Banner/The Hulk), Tom Holland (Peter Parker/Spider-Man), Jeremy Renner (Clint Barton/Hawkeye), Chris Pratt (Peter Quill/Star-Lord), Paul Rudd (Scott Lang/Ant-Man), Benedict Cumberbatch (Dr. Stephen Strange), Brie Larson (Carol Danvers/Captain Marvel) and so many more from the Marvel Cinematic Universe — opens May 4, 2018.

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