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When Mark Engstrom arrived in Newfoundland to salvage a blue whale carcass, he was bracing himself for the epic stink characteristic of a decomposing whale. In fact, since this beast is the most massive animal that ever lived, “the smell was twice as big as usual”, he says.

Coming across a blue whale carcass is rare because the animals usually sink when they die. But in April 2014, two washed ashore on the east coast of Canada. This allowed Engstrom and his team from the Royal Ontario Museum in Toronto to dismember one animal and study it. They carefully removed the bones to reconstruct the skeleton, and kept various parts like fat, baleen and an earwax plug – whose tree-like rings can be counted to determine age. “It took six days,” says Engstrom.

Now a multisensory exhibition at the museum brings the animal back to life. It contains the world’s most complete blue whale skeleton, as well as some of its supersized body parts, and a recreation of some of its unique traits. Visitors can even walk into a cast of the whale’s jaws.

The show also delves into the mysteries the team is trying to solve. “We’re interested in finding out how it has been changed by evolution,” says team member Oliver Haddrath. Examining the whale’s genes should provide clues. Haddrath has been working on sequencing its genome from DNA extracted from a fin, the best-preserved body part since it remained immersed in cold seawater.

The team hopes to answer questions, such as how the blue whale lost its teeth and colour vision. Whales see in black and white and are sensitive to blue light, which gives them better vision in the dim depths where they hunt the krill that make up almost all their diet. Visitors can experience what a krill swarm looks like to a whale via a new simulation, says Haddrath.

The genome should also help estimate the size of past populations. Blue whale numbers fell dramatically in the early 1900s because of factory ship whaling – producing oil and other products from blubber – but there are no solid figures. The genetic diversity of just a few individuals could shed light on those numbers, which in turn would help to reveal the fate of current populations. For example, “People are now saying [blue whales off the California coast] are back to pre-hunting numbers but if we don’t know what those were, we can’t make that claim,” says Haddrath.

“Coming across a blue whale carcass is rare as the massive animals usually sink when they die”

The blue whale’s heart, which is the largest of any animal, is also enigmatic because few have been recovered before. Visitors can see the heart, immortalised using plastination techniques. After the show, its anatomy and function will be studied.

The team was surprised to find that the heart didn’t live up to rumours of being as big as a car. “It might fit inside a small car, but it’s not the massive structure that we thought it was,” says Jacqueline Miller, who worked to preserve it.

The hearts of most land mammals account for 1.5 per cent of their body mass. But from the team’s initial calculations, the heart from their whale makes up about 0.25 per cent of the creature’s body mass. If it is indeed the case, they are curious to find out why, as well as how it manages to function.

The team has also recreated the blue whale’s sound, the loudest of any animal. In one room, a projection gives visitors the impression that a blue whale is swimming next to them while they feel vibrations from its calls, which are partly outside the range of human hearing.

And the experience wouldn’t be complete without a whiff of dead whale. Engstrom thinks he has cracked it, but he’s keeping the process secret.

This article will appear in print under the headline “Thar she blows”