Big changes are happening at the Natural History Museum in London, and not everyone is pleased. For decades, Dippy the dinosaur has greeted visitors in the entrance hall, making him a symbol of the museum. But his reign is coming to an end, according to BBC News.

The museum will replace Dippy with another permanent resident, the skeleton of a massive blue whale that currently hangs in the mammals gallery. Instead of being positioned horizontally, as it is currently, the whale will be mounted in a dramatic diving pose.

Museum staff believe the whale is a much better specimen to have in the entrance hall, scientifically speaking. Dippy isn’t even a real dinosaur. He’s replica of a real Diplodocus carnegii skeleton and is made out of plaster.

Sir Michael Dixon, director of the museum, said of the change, "Everyone loves 'Dippy', but it's just a copy, and what makes this museum special is that we have real objects from the natural world — over 80 million of them — and they enable our scientists and thousands like them from around the world to do real research."

But if dinosaurs have taught is anything, it's that change can be hard. Response to the news sparked a #savedippy campaign on Twitter and an online petition.

For those who don’t believe that Dippy should be dethroned, don’t worry. The dinosaur won’t go far. The museum hopes to include Dippy in a larger exhibit, perhaps even weatherproofing the replica bones and putting Dippy outside. Dippy also might go on tour so that even more people will be able to meet him, and learn about dinosaurs.

The blue whale set to take Dippy’s place is a complete specimen. The 82-foot giant dates back to the 1800s. After being injured by a whaler, the cetacean was found beached on the southeast coast of Ireland. The body was stripped for oil and meat, and then the skeleton was sold to the Natural History Museum in 1891 for £250 (that's about $377 today). Decades later, in 1935, the whale was displayed for the world to see.

The blue whale brings with it an important environmental message, one the museum is eager to share.

Blue whale skeleton at London's Natural History Museum The blue whale skeleton is a more complete specimen. (Photo: Denis Bourez/Natural History Museum/Wikimedia Commons)

“As the largest known animal to have ever lived on Earth, the story of the blue whale reminds us of the scale of our responsibility to the planet," says Dixon. “This makes it the perfect choice of specimen to welcome and capture the imagination of our visitors, as well as marking a major transformation of the museum.

“This is an important and necessary change. As guardians of one of the world’s greatest scientific resources, our purpose is to challenge the way people think about the natural world, and that goal has never been more urgent.”

Blue whales, once abundant, were nearly hunted to extinction in the 20th century and were only saved once they became a protected species in 1972, according to The Independent. Since that time, the species’ number has risen from just 10,000 to now 25,000, coming back the strongest along the California coast. Unfortunately, populations in Antarctica haven’t had the same good fortune.

Dixon said of the skeleton’s significance as an environmental symbol, “Species and ecosystems are being destroyed faster than we can describe them or even understand their significance. The blue whale serves as a poignant reminder that while abundance is no guarantee of survival, through our choices we can make a real difference.”

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