According to some accounts, early settlers when building new villages sometimes accidentally dug up grave sites of “indians” who were extremely tall - 7-8 feet.
When he heard about these finds, James Smithson who was married to and Indian, began gathering these finds up and taking them back to D.C. There, he stored them in the basement of the museum which is now called the Smithsonian ... where thay remain unseen and uncatalogued.
Smithson had a reason for this action which I do not remember, but I believe had something to do with politics and Indian lore.
Very tall indians today are not that uncommon, I was told by an Indian I knew.
From Buffalo Bill Cody’s autobiography:
“While we were in the sandhills, scouting the Niobrara country, the
Pawnee Indians brought into camp some very large bones, one of which
the surgeon of the expedition pronounced to be the thigh bone of a
human being. The Indians said the bones were those of a race of people
who long ago had lived in that country. They said these people were
three times the size of a man of the present day, that they were so
swift and strong that they could run by the side of a buffalo, and,
taking the animal in one arm, could tear off a leg and eat it as they
ran.
These giants, said the Indians, denied the existence of a Great Spirit.
When they heard the thunder or saw the lightning, they laughed and
declared that they were greater than either. This so displeased the
Great Spirit that he caused a deluge. The water rose higher and higher
till it drove these proud giants from the low grounds to the hills and
thence to the mountains. At last even the mountaintops were submerged
and the mammoth men were drowned.
After the flood subsided, the Great Spirit came to the conclusion that
he had made men too large and powerful. He therefore corrected his
mistake by creating a race of the size and strength of the men of the
present day. This is the reason, the Indians told us, that the man of
modern times is small and not like the giants of old. The story has
been handed down among the Pawnees for generations, but what is its
origin no man can say.”
http://www.fullbooks.com/An-Autobiography-of-Buffalo-Bill-Colonel-W-F3.html