Melanie and the Pot of Jam is a colourful picture book adventure for young children but it also has a message about healthy eating. In the story, Melanie is an ordinary fruit fly that feeds on fruit until one day she is attracted to an open pot of strawberry jam, that also happens to be her favourite fruit. So engrossed in eating the jam, she fails to notice someone putting the lid on and returning the pot to the fridge. It is cold and dark in the fridge, so what is a fruit fly supposed to do to keep warm when she is surrounded by her favourite fruit, although it is in the form of sugary jam. While trapped in the pot she continues to eat jam not realising that she is putting weight on. Finally, the pot of jam is removed from the fridge and she sees that she has gained considerable weight. It is really hard but she manages to fly out of the pot once the lid is removed and escape two girls who try to swat her. Luckily for her there is an open window in the kitchen. Once outside she decides to return to her svelte former self by going to the insect gym. At the end of the story, she vows to eat mainly fruit in the future with just the occasional bite of jam. With obesity increasing to worrying levels through the consumption of processed foods, especially in children, the story is about eating a healthy diet with certain foods in moderation.

Melanie is a fruit fly from the species called by its scientific name, Drosophila melanogaster. Few are going to remember that name so the main character in the story prefers to be called Melanie. So, in real life fruit flies feed on fruit and other sugary substances. Fruit flies are found almost everywhere apart from Antarctica and it is us humans that have helped to spread them. While they may bother the average household hanging around fruit bowls, especially those that have bananas in them, they have become an incredibly important species for medical and scientific research, with five Nobel prizes having been awarded with work that involved Drosophila melanogaster. It was in 1901 that the American entomologist, Charles William Woodworth, bred the flies in captivity and suggested that they could be used for early genetic research at Harvard University. Perhaps the best-known early work based on using the fruit fly was that carried out by Thomas Hunt Morgan who won a Nobel prize in Physiology or Medicine in 1933. An urban myth perhaps, links Morgan's use of the fruit fly to one of his team leaving a rotten banana in a lab rather than a human chain connection back to Woodworth. Whatever is the truth, the humble fruit fly has been and continues to be a very important creature to study in terms of medicine and science.