The missing Malaysia Airlines flight MH370 may have drifted further south than search parties believed, a study of barnacles has shown.
Marine biologists noticed that barnacles were attached to plane debris which washed up on Reunion Island off the African coast, 16 months after the flight went missing over the Indian Ocean in October 2014.
Barnacles and other shelled marine invertebrates grow their shells daily, producing internal layers similar to tree rings.
The chemistry of each layer is determined by the temperature of the surrounding water at the time the layer was formed and can be used to determine where the creature was on any given day.
Experts realised they could use the barnacles as a history of where the debris had been, perhaps even tracing it back to the original crash site.
So far they have only managed to study young barnacles from the debris, which has told them the plane debris was probably south east of Reunion island about five months before it washed up.
Now they are hoping to get hold of larger barnacles from the debris to run the clock back even further.
Dr Gregor Herbert, Associate Professor from the University of South Florida, said: “The [debris] was covered in barnacles and as soon as I saw that, I immediately began sending emails to the search investigators because I knew the geochemistry of their shells could provide clues to the crash location.
“Sadly, the largest and oldest barnacles have not yet been made available for research, but with this study, we’ve proven this method can be applied to a barnacle that colonised on the debris shortly after the crash to reconstruct a complete drift path back to the crash origin.”
The search for MH370 was carried out over several thousands of miles along a north-south corridor deemed “The Seventh Arc”, where investigators believe the plane could have glided after running out of fuel.
But the new results suggest the plane may have drifted further south in the Indian Ocean, into waters that were around 2C warmer.
French scientists who carried out initial tests on the debris reported that some barnacles attached were old enough to have colonised the wreckage very shortly after the crash, but they have so far resisted attempts to hand over the shells for further analysis.
Dr Herbert added: “No one can do any work on the larger barnacles until the French change their minds, but our publication lays a clear pathway for what needs to be done and why it should work.
“Our drift modelling method is first to show how we can find the most likely drift pathway from all the temperatures recorded by a hitchhiking barnacle during its journey on a piece of debris.”
Nassar Al-Qattan, a recent USF geochemistry doctoral graduate who helped analyse the geochemistry of the barnacles, said: “Knowing the tragic story behind the mystery motivated everyone involved in this project to get the data and have this work published.
“The plane disappeared more than nine years ago, and we all worked aiming to introduce a new approach to help resume the search, suspended in January 2017, which might help bring some closure to [the families] of those on the missing plane.”
The research was published in the journal AGU Advances.