The general consensus has been that the plane had run out of fuel and crashed in the Pacific Ocean, somewhere near Howland Island.
But according to Gillespie, the "volume of evidence" TIGHAR has gathered suggests an alternative scenario.
"Propagation analysis of nearly 200 radio signals heard for several days after the disappearance make it virtually indisputable that the airplane was on land," Gillespie said.
Eventually, Earhart's twin-engine plane, the Electra, was ripped apart by Nikumaroro's strong waves and swept out into deep water, leaving no visible trace.
"The evidence is plentiful -- but not conclusive yet -- to support the hypothesis that Amelia landed and died on the island of Nikumaroro," forensic anthropologist Karen Ramey Burns told Discovery News.
The author of a book on Earhart, Burns believes that the strongest of the amassed evidence comes from the report related to the partial skeleton found by Gallagher.
"The skeleton was found to be consistent in appearance with females of European descent in the United States today, and the stature was consistent with that of Amelia Earhart," said Burns.
According to Burns, another piece of documentary evidence comes from the accounts of Lt. John O. Lambrecht, a U.S. Naval aviator participating in the search for Earhart's plane. Lambrecht reported "signs of recent habitation" on what was an officially uninhabited atoll.
Lambrechet's report begs the question: Why did no one follow up?
"I have stood in plain sight on Nikumaroro in a white shirt waving wildly as a helicopter flew over me and was not noticed until the video tape of the flight was examined," Burns said.
"I find it very easy to believe that Amelia and Fred would not have been seen by the pilot. If the Electra was not visible at the time, their last chance of rescue was lost in Lambrecht's notes," she added.
Abandoned on a desert island where temperatures often exceed 100 degrees, even in the shade, Earhart and Noonan likely eventually succumbed to any number of causes, including injury and infection, food poisoning from toxic fish, or simply dehydration.
The coconut crabs' great pincers would have done the rest, likely removing some of the last physical traces of this pioneering aviatrix.