Tne mysterious Neanderthal-like skulls in Minnesota
In the internet there are several sites that are “copy-pasted clones” of each other, dealing with an alleged cover-up by the Smithsonian Institution: the deliberate “loss” of some unusual skulls sent to them from an archaeological dig in Minnesota in 1968). To see them, just Google the keywords “great Smithsonian cover up”. Lets look at what facts can be found beyond the cloned posts and sites:
Original text source
The online posts quote a book written by Vincent Gaddis and published in 1977,  which states the following (yes, I am copying and pasting):
In 1968 two Neanderthal-like skulls with low foreheads and large brows were found in Minnesota. As for dating, University of Minnesota scientists said they were reluctant to destroy any of the material, although carbon-14 testing only requires the burning of one gram of bone. They were sent to the Smithsonian. Later Dr. Lawrence Angel, curator of physical anthropology at the institution, said he had no record of the skulls there, although he was sure they were not lost. 
The text mentions a “Dr. Lawrence Angel” and “University of Minnesota scientists” gives a date (1968) and not mouch more. Lets see what can be found.
An entry in a publication of the “Instituto Interamericano” of Denton, Texas, US, which is shown in the image below , and whose text is copied further down (I have highlighted the interesting parts in bold):
RARE BONES: Human skulls, bones and artifacts were found near Ely, Minnesota, in 1968 but have just now been publicly reported. The exact site of the find is being kept secret for fear of looters. Dr. Eldon Johnson, Minnesota state archaeologist, said that the extremely low foreheads and heavy brow ridges suggest that the skulls are examples of what must have been either an early type of man or an inbred population. “the skulls may well represent a pre-Indian type of man that is more closely related to Neanderthal man than any previously found in America” said Dr. Richard Adams and leader of the University of Minnesota team which first examined the find. Dr. T. Dale Stewart of the Smithsonian has the bones and will determine if they are sufficiently unique to warrant a C-14 test... 
This snippet has given us the names of three people involved in the finding, Eldon Johnson, Richard Adams and Dale Stewart, besides Lawrence Angel mentioned in the original article. Details on these men below:
1. Elden Johnson (1923-1992). Actually the name is wrong, the state archaeologist is really Elden and not Eldon. And he was also part of the University of Minnesota (210 Ford Hall, University of Minnesota, Minneapolis, Minnesota 55455). However, the “Minnesota Archaeological Newsletter” (click to read it online) mentions Mr. E. Johnson several times, but, during the 1967-1972 period has not one entry regarding skulls of Neanderthal men found in Minnesota.
Furthermore, the online biography (Minnesota Univ.) does not mention the skulls or anything related to them. 
2. Lawrence Angel. He was a very busy man during the period of the “Minnesota findings” as we can see in his papers: 
1962-1986. Curator, Division of Physical Anthropology, Department of
Anthropology, United States National Museum (later the National Museum of Natural History), Smithsonian Institution, Washington, D.C.
1967. Field work in the Near East: Turkey, studied skeletal remains from
Catal Huyuk at the University of Ankara, and skeletons from Antalya, Elmali, and Karatas; Greece, studied skeletal remains from Franchthi cave, Athens, Kea, Nauplion, Corinth, and Asine; supported by the Hrdlicka Fund. Organized a symposium on paleodemography, diseases and human evolution at the 66th meeting of the American Anthropological Association in Washington, D.C. 1969. Field work in the Near East: studied material from Kephala, Karatas, and Franchthi cave; supported by the Hrdlička Fund and the Wenner-Gren Foundation.
1970. Visiting Professor, Harvard University (Spring). Organized the 39th
meeting of the American Association of Physical Anthropologists held
in Washington, D.C.
1971 The People of Lerna: Analysis of a Prehistoric Aegean Population.
1972. Field work in the Near East: studied skeletons from Asine and Agora
in Greece; supported by the Hrdlička Fund.
1962-1986. Professorial Lecturer in Anthropology at George Washington
University, Washington, D.C.
1963-1986. Lecturer in forensic pathology, The Johns Hopkins University School of Public Health.
1965-1970. Visiting Professor of Anatomy, Howard University Medical School, Washington, D.C.
This means that he may have not been aware of a package with “Neander” bones sent to the Smithsonian in 1968.
3. Richard Adams (1931-?). His online biography states that his field is Latin American archaeology and especially the Mayas. “Adams has been to the Rio Bec region in the central Yucatan peninsula several times from 1969 to 1973. In an excavation from 1969 to 1971 .  So he probably did see the bones in 1968 and then moved on to other things.
His bio does not mention them. He has not written about them.
4. Dr. T. Dale Stewart (1901-1997). He began working at the Smithsonian Institution in 1924, becoming curator in 1931, and working under Ales Hrdlicka. In 1961, he became the head curator of the Department of Anthropology, and in 1962, director of the Smithsonian Institution National Museum of Natural History. During the period mentioned (1968-1972), he was the senior scientist in the department of anthropology. He retired in 1971. 
Though he upheld Hrdlicka’s view on an Asian origin for Americans, he thought that the arrival of humans to America happened at an older date than the one proposed by Hrdlicka (who was strongly in favor of a recent arrival). He studied Neanderthal remains in Asia. 
He does not seem to be the kind of scientist who would deliberately destroy or conceal “old” bones, which in fact upheld is beliefs.
www.cryptomundo.com also mentions the skulls, and gives two references which are copied below for those interested in reading the original sources: 
- Gordon Slovut, “Old Skulls Have State Expert Scratching Head”. Minneapolis Star, 12 July 1972.
- Associated Press dispatch from Ely, Minn., 12 July 1972.
It also places the site where the bones were found at: the Boundary Waters Canoe Area, Minnesota.
So, not one of those mentioned in sources  or  seem to have written any papers on this amazing finding. One of those involved supported the notion of an "ancient" peopling of America. Why would any of them have contrived to make the bones disappear? Maybe the remains just got lost or misplaced.
Anyway, if true, it points towards "thick browed" native Americans date unknown that, may actually have been "American Homo erectus" who evolved from Asian stock in America and thus resembled Neanderthals.
 Vincent H. Gaddis, (1977). American Indian myths & mysteries, Chilton Book Co.
 Carl B. Compton, The Interamerican. “Rare Bones”. Vols 14 to 23.
 Robert Lynn Montgomery, (1994). Register to the Papers of John Lawrence Angel. Revised by Jennifer Chen, Jill Fri and Gayle Yiotis, 2006. National Anthropological Archives, Smithsonian Institution.
 Sources www.cryptomundo.com.
 Smithsonian Institution. Thomas Dale Stewart Papers 1954.
 Minnesota State University, Mankato. R. Adams’ bio.
 Same site, E. Johnson’s bio.
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