during 70000 the first thing even like glue, was oiled down, and used what was demeaned they added pigment, it could be blood or berries. This was the paint  they used on cave walls. So it wasn’t glue. The first real glue was 2000bc approx 4000 years ago.

How do we know? Becaus we found relics or antiques that needed glue.

Then 300 years ago their was a stage called horse glue. Once your horse was like really old and useless you would sell your horse and bring it back to a factory.

then roughly  102 years ago… about 1918 they discovered and developed rubber glue, but wasn’t used that much. Then in world war 2 theY found out 5he thin* milk glue. You use the scraps I guess of the milk after it’s been separated.