Amelia Earhart
Earhart standing beside a plane, circa 1928Los Angeles Daily News public archives

A new theory put out this week provides one additional link between bones recovered on a Pacific atoll in 1940 and pilot Amelia Earhart. But since the partial skeleton mysteriously disappeared more than 75 years ago, will we ever know if it was indeed the most famous aviatrix in history?

Forbes has reported that sometime in the spring of 1940, a local living on Nikumaroro, an island in the nation of Kiribati in the south Pacific, found a skull and a bottle.

On September 23 of that same year, Gerald "Irish" Gallagher, the officer in charge of the Phoenix Islands Settlement Scheme (a colonial scheme of the British Empire that sought to populate previously unpopulated islands like Nikumaroro), sends a telegram to his administrative office in Tarawa urging them not to talk about a skull which he noted was quite possibly that of Amelia Earhart.

The British doctor, DW Hoodless, of the Central Medical School in Suva, Fiji, who examined the remains declared that they were they were from a short stocky male and could not be Earhart, according to a press release.

The bones eventually went missing, but in 1998, The International Group for Historic Aircraft Recovery (TIGHAR) researchers examining old files on the disappearance came across the doctor's report and took the recorded measurements to forensic anthropologists for reexamination.

Amelia Earhart

These researchers studied the data and compared the measurements to current larger databases of expected bone dimensions based on sex, age and race, concluding that the "measurements taken at the time appear consistent with a female of Earhart's height and ethnic origin."

The Smithsonian reports that when one of the anthropologists was recently updating this evaluation, however, he noticed that the ratio of the length of the skeleton's humerus, or upper arm bone, and radius, one of the bones in the forearm, was 0.756.

Women of Earhart's day typically had a ratio of 0.73, meaning that if the skeleton was from a woman of European ancestry, her forearms were longer than average, according to the press release.

TIGHAR contacted forensic imaging specialist Jeff Glickman, who evaluated a historical image in which Earhart's bare arms are visible. According to his report, the ratio of Earhart's humerus and radius that he could estimate from the photo is 0.76, very close to the ratio from the medical exam.

"The match does not, of course, prove that the castaway was Amelia Earhart, but it is a significant new data point that tips the scales further in that direction," TIGHAR's executive director Richard Gillespie tells Rossella Lorenzi at Discovery News.

However, as Kristina Killgrove writes for Forbes, this new analysis may be questionable.

The amount of error associated with these ratios, known as the brachial index, is unknown. This means that the error associated with the measurement could make this slight difference irrelevant.

"If the errors in this sort of analysis are typically small, they may not change the brachial index. But if the errors tend to be large, that index could change dramatically," Killgrove writes.

The spotty case for Earhart's survival for a few days on the island has grown over the years.

In 1991, during an expedition to the island, the researchers discovered a scrap of aluminium. Later analysis showed that the pattern of rivet holes was similar to the patches used to repair Earhart's Lockheed Electra.

Also in 1991, the researchers found the fragments of an old shoe—likely a mid-1930s woman's size nine blucher oxford with a recently replaced heel and brass eyelets. Photos show Earhart wearing the same type of shoe ten days before she disappeared.

Some also suggest that Earhart made up to 100 radio transmissions between July 2 and July 6, which were picked up by radio operators.

But none of this evidence is airtight, and the mystery behind her final resting spot remains unsolved.

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