Tree resin you can get ahold of on accident, light a green piece of wood on fire, you get glue. Animal products can turn to glue with again just leaving it in a fire a long time or a hot enough fire. Humans have been making stone and other tools a lot longer than Homo Sapiens have been around.
Like what? Spit? Poop? Semen?
Like gelatin, casein, starch, horn glues? They are old as dirt.
Tree resin you can get ahold of on accident, light a green piece of wood on fire, you get glue. Animal products can turn to glue with again just leaving it in a fire a long time or a hot enough fire. Humans have been making stone and other tools a lot longer than Homo Sapiens have been around.
Where do you think Gorilla Glue comes from?
Gorilla bukake factory?
Dicks out for Harambe