The longest neck any animal has ever grown belonged to Mamenchisaurus, and the neck on its own was more than 15 metres, longer than a school bus before you even get to the rest of the dinosaur. Which raises the obvious question: how do you hold something like that up? The answer is that mostly you don’t have to, because sauropod neck bones were never solid. They were full of air.

That is this week’s word. Pneumatic bone is built like a honeycomb, riddled with air spaces a millimetre or two across, which makes it far lighter and, oddly, no weaker at all. Birds have the same trick, which is part of how they get off the ground, and birds are dinosaurs. On Mamenchisaurus roughly half the animal’s total length was neck, carried on as many as 19 neck bones. A giraffe, the record holder among mammals at 2.2 metres, manages with seven. So do you.

Fresh from the Dig has a Diplodocus found underneath a car park at Dinosaur National Monument in Utah, where people had been parking on top of it for years. Only the part in the way of the building work has been dug out, and the rest has been left in the ground for future palaeontologists. Plus Mamenchisaurus and its two seconds of screen time in The Lost World, and Cetiosaurus, the whale lizard, dug up in Oxfordshire and named in 1841 by Richard Owen, who took one look at bones that size and decided they had to belong to a whale. It was the first long-necked dinosaur ever named, and it is stuck with the name.

Lauren and Cassius are joined by Dr Mike Taylor, a computer programmer by day who studies sauropod necks in the evenings. He explains why taking bone out of the middle of something makes it stronger rather than weaker, suggests boiling down a turkey neck at Christmas so you can see the air spaces for yourself, and points out that nobody needs permission to do palaeontology. Two of his colleagues had their first scientific papers published while they were still at school.

Elsie, who is eight and from Bristol, wants to know how many bones are in a sauropod’s neck. Then it is Build a Dino Lab, where one real fact becomes one real piece of the perfect dinosaur. Week two is long neck or short, and Lauren goes short, because 15 metres of neck on a two-legged dinosaur ends with its face in the mud.