Caltrops - a Device Built After Nature

[VANDOO]

I AM PRETTY SURE THE CALTROP GOES BACK TO ROMAN TIMES AND IS STILL USED IN THE PRESENT. VIETNAM PUNJI STAKES IN RICE PADDIES AND TALL GRASS.
THERE ARE THE ONE WAY TRAFFIC TREADLES USED IN PARKING LOTS AND GARAGES TO SHREAD TIRES. THE SPIKE STRIPS USED BY THE POLICE AND MILITARY AND A THING REFERRED TO AS THE SQUID DESIGNED TO STOP VEHICLES WITH NON PUNCTURING TIRES AND SUCH. SEARCH SPIKE STRIPS.
THE BARBED AND CONCERTINA WIRE MAY HAVE EVOLVED FROM THE SAME IDEA. WHATEVER THE CASE THE PLANT KINGDOM THOUGHT OF IT FIRST.