An online campaign has been launched to help stop Dippy the Diplodocus being put out to pasture by the Natural History Museum.
#SaveDippy has become a monster trending hit on Twitter as supporters rally to save him.
The news that the 85-foot-long plaster dinosaur skeleton is to be moved out of the museum's main hall to make way for a blue whale quickly set the social media site alight.
Hundreds of people voiced their surprise and outrage, using the hashtag #SaveDippy, and signed an online petition calling for the decision to be dropped. Words: PA
Dippy, who has been at the London museum for more than a century and greeted wonder-struck children filing into the Hintze Hall since 1979, now has his own Twitter account, @SaveDippy with a rapidly rising number of followers.
His personal description reads: "Natural History Museum dinosaur looking for work. Forced into retirement at the young age of 150 million. Still have life left in me #SaveDippy."
From summer 2017, Dippy will be replaced by the 83 foot long (25.2 metres) real skeleton of a blue whale, suspended and "diving" from the ceiling of the Hintze Hall.
The change is part of a "decade of transformation" planned at the museum by its director, Sir Michael Dixon.
He explained that the museum wanted to focus on the "real and authentic" and tell a story that is relevant to the natural world today.
Dippy is a fake - one of 10 replicas around the world based on the near-complete skeleton of a real Diplodocus unearthed in Wyoming, US, in 1898 and housed at the Carnegie Museum of Natural History in Pittsburgh.
In contrast the female blue whale is the genuine article. The huge creature was found beached at the mouth of Wexford Habour, Republic of Ireland, on March 25, 1891, after being injured by a whaler.
Its bones were sold to the Natural History Museum for £250 and eventually put on public display with the opening of the Mammal Hall in 1938.
By 1pm today the SaveDippy petition organised by Metro UK had collected more than 700 signatures.
The petition says: "Despite being a fake, Dippy is loved around the world and is a monument of British heritage.
"Replacing Dippy with a blue whale skeleton would threaten this and lead to many unhappy faces in the UK youth.
"We demand Dippy is saved and remains in the main hall forever."
Future plans for Dippy are uncertain but include the possibility of a national tour and making a copy of him out of more durable material that can stand in the museum grounds.
Eventually the resin skeleton is expected to find a new home in one of the museum's galleries.
Dippy's fans include Huddersfield Labour MP Barry Sheerman, who wrote: "Rather sad about the removal of Dippy the Dinosaur from star billing @NHM_London Can we have it in Yorkshire?"
George Jenkins @gj253 wrote: "Can't believe the natural history museum is retiring Dippy the Diplodocus, he's an icon!"
Stuart Robinson @LeedsClarkKent said:"Absolutely gutted! First thing I saw on my very first visit as a nipper, one of my happiest childhood memories."
And Ruaridh Arrow @ArrowontheHill declared: "Removing Dippy from the @NHM_London is like removing the Eiffel Tower from Paris."
Speaking after the news of Dippy's departure was announced, Sir Michael said: "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.
"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."
Dippy was unveiled in the Natural History Museum's Reptile Gallery on May 12 1905.
He was donated to the Museum by Scottish-born American millionaire and philanthropist Andrew Carnegie after King Edward VII saw an illustration of the original skeleton and asked for a copy.
The skeleton, which contains 356 plaster cast bones, was constructed over a period of 18 months and shipped to England in 36 crates.
To avoid damage during the Blitz, Dippy was taken apart and stored in the Natural History Museum's basement. In 1979 he was rebuilt and given pride of place in the central hall.
The #SaveDippy campaign was started by well known children's author James Mayhew, creator of the Katie and Ella Bella Ballerina series.
He wrote: "Starting a campaign here on twitter. @NHM_London are getting rid of their diplodocus! Please reconsider, we love him! #savedippy".
Commenting on the Twitter reaction, Sir Michael offered sympathy to Dippy fans, but no hint of a change of heart.
He said: "After inspiring millions of visitors over 35 years, it's no surprise to me that some want to keep the Diplodocus centre stage.
"We love Dippy too. Once it leaves Hintze Hall, taking the Diplodocus on tour would inspire many more millions of people and, given the public response, we will now see how we can involve people in making this tour happen. In the longer term, Dippy is destined to find a new home back in South Kensington.
"I believe the whale's story links directly to our species' impact on the natural world and our chance to build a sustainable future. We're looking forward to showing that the blue whale can be equally stunning and it will connect the visitors to the work of scientists in the Museum."