Let me tell you about the Loess Man of Nebraska:

In 1894, a skull was uncovered that could not be identified.  Then 12 years later Robert Fletcher Gilder from the University of Nebraska found a similar skull.  Both were found in mounds about 4 feet deep.  The first skull was sent to Robert Gilder.  After examining both skulls he said they were the remains of  the Neanderthal Man.

In the November 16, 1906 issue of Science Magazine, Robert Gilder said the skulls are of the Neanderthal type.  With protruding brows, low forehead, devoid of frontal eminences, large parietal eminences, narrow temple, thick skull wall and small brain capacity.

Then in 1907, another book was written by an anthropologist Ales Hrdlicka called Skeletal remains suggesting or attributed to Early Man in North America, tried to discredit Robert Gilder's finding on the skulls he found.  He claimed that they had to be modern skulls and not Neanderthal because:  

1. Shallow depth of 4 feet of the mound.
2. Bones had not fossilized
3. Mice had chewed the bones because of the found rodent bites.  He surmised that the mice took the bones and dragged them to their burrow, the burrow collapsed which made the bones appear deeper.
4. Then he said that it was common for the contemporary natives to have sloping foreheads and pronounced brow ridges.
5. He also mentions other mounds that had similar Neanderthal-like skulls.  ?!? 

Now I would like to point out a few things:

1. Within the mounds many of the skulls were fragmented and dispersed.  Which would be unexpected for a controlled burial.  So the assumption it must be mice that made the skulls and bones be deeper seems far fetched if there were no remains of mice since he is assuming the burrow collapsed.
2. Were all the mounds found be contributed to mice and their burrow collapsing?  Does that even make sense?  Is this an actual fact about the mounds?  Were there rodent bites on all the skulls found?
3. It is not common for the contemporary natives to have sloping foreheads and pronounced brow ridges.  It wasn't a common characteristic like he claimed. 
4. The thickness of the skulls point not to human but to something else.
5. Have all the known Neanderthal remains that were found before these skulls in other parts of the world been fossilized remains?  Were any found like these skulls?
6. Could they be something else if not Neanderthal? 

I will state right now that I am not an expert but I do have a brain and can analyze what I have read.  It seems to me that there are some questions that our science community is not sharing with the general public.  Until recently I have never been taught, or had read or watched anything about mounds or remains that look human-like but are not.  Why?

Either the history of when humans came to North America that is perpetuated to us is wrong and they are hiding the truth from us

or

There are other human-type species living here in North America.  That are big, with thick skulls, with sloping foreheads and pronounced brow ridges.

So if those bones were actually not ancient but from a modern species then either we have Neanderthals running around in North America or maybe they could be Sasquatch.