I'm going to try to not be adversarial but no. We did it all on our own. There are some things lost to antiquity like Greek fire. But by and large we have equaled or surpassed the efforts of our ancestors. Just because we forgot doesn't mean we didn't do it.

Most of these things have been recreated by modern humans using stone/bronze age technology, and that is without even the years of experience, that the original people would have had.
I love this one, it has no real academic merit, but it is great fun.

There is a Podcast with two people who have done a lot of research on both of these places, interesting. There are also some places in Southern Brazil that have just been seen for the first time due to the burning done for crops. The Podcast was with Joe Rogan, unfortunately I think the books are packed for moving. If I find them or the people I can tell you who they are if there is interest. Actually if there is interest I will look up the people.

Yup

The argument from incredulity fallacy is strong here. It's really arrogant to think that because you cannot explain something it can't be explained. This has been thoroughly debunked, and aliens, seriously?

Sounds like someone has been watching too much Ancient Aliens. Just because we can't explain it, that doesn't cut the muster for making the leap to a conclusion about ancient aliens or advanced ancient tech. Humans have been doing amazing things for hundreds of thousands of years. To think that we are now so much more advanced 'technologically' is directly related to our understanding of what technology is. I tend to see it somewhat like what happens when one of your senses is diminished and it leads to the heightening of other senses. In ancient times, sans what we think of as technology, I suspect human imagination and creativity still managed to solve a lot of their period's problems. We just aren't quite able to see the forest for the trees because we all here have lived in a time when our every act of daily living relies on such technological advances. Spend some time with people who still live very primitively, and you quickly see that simple lack of formal education and technology isn't much of a barrier to overcoming life's obstacles as it is known to be outside of 'civilization'.

People were just as smart and resourceful as they are today, probably more so. No I don't believe in spacemen visiting the Earth. No I don't think there has been technology that was as advanced as it is today. Maybe as advanced as 200 years ago but not where we are today. I'm a skeptic and they is no evidence for that and I "STILL deny" that little green men visited the Earth.

The latest theory about Nazca lines is that they were part of religious rituals, much like the coils and spirals which some Buddhists walk as they pray. It's not all that complex to imagine them being scraped from the very arid soil. Ropes of standard lengths could be used to guarantee the lines within the figures were equidistant.

A couple of them do have errors but mostly, they're very precise. At least one large temple complex is being excavated and it's thought the line-builders were part of that society.

We never give earlier people enough credit for having brains, technical minds, math skills, astronomical knowledge and the ability to plan and use tools. Remember that the lines were created about 500 years BCE...the pyramids in Egypt were already old. People in Aztec, Olmec and Maya cultures built amazing things both before and during the Nazca civilization.

Edited to add that I hope you'll have the chance to fly over the figures at least once! They're amazing.
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