An extract on #taptwice
Metal detectors were first used for demining, after their invention by the Polish officer Jzef Kosacki. His invention, known as the Polish mine detector, was used by the Allies alongside mechanical methods, to clear the German mine fields during the Second Battle of El Alamein when 500 units were shipped to Field Marshal Montgomery's Eighth Army.
The Nazis used captured civilians who were chased across minefields to detonate the explosives. According to Laurence Rees, "Curt von Gottberg, the SS-Obergruppenfuhrer who, during 1943, conducted another huge anti-partisan action called Operation Kottbus on the eastern border of Belorussia, reported that 'approximately two to three thousand local people were blown up in the clearing of the minefields'."
Whereas the placing and arming of mines is relatively inexpensive and simple, the process of detecting and removing them is typically expensive, slow, and dangerous. This is especially true of irregular warfare where mines were used on an ad hoc basis in unmarked areas. Anti-personnel mines are most difficult to find, due to their small size and the fact that many are made almost entirely of non-metallic materials specifically to escape detection.
Manual clearing remains the most effective technique for clearing mine fields, although hybrid techniques involving the use of animals and robots are being developed. Animals are desirable due to their strong sense of smell, which is more than capable of detecting a land mine. Animals like rats and dogs can also differentiate between other metal objects and land mines because they can be trained to detect the explosive agent itself.
Other techniques involve the use of geo-location technologies. A joint team of researchers at the University of New South Wales and Ohio State University is working to develop a system based on multi-sensor integration.
The laying of land mines has inadvertently led to a positive development in the Falkland Islands. Mine fields laid near the sea during the Falklands War have become favorite places for penguins, which do not weigh enough to detonate the mines. Therefore, they can breed safely, free of human intrusion. These odd sanctuaries have proven so popular and lucrative for ecotourism that efforts exist to prevent removal of the mines.
Most lizards are quadrupedal, running with a strong side-to-side motion. Others are legless, and have long snake-like bodies. Some such as the forest-dwelling Draco lizards are able to glide. They are often territorial, the males fighting off other males and signalling, often with brightly colours, to attract mates and to intimidate rivals. Lizards are mainly carnivorous, often being sit-and-wait predators; many smaller species eat insects, while the Komodo eats mammals as big as water buffalo.
Lizards make use of a variety of antipredator adaptations, including venom, camouflage, reflex bleeding, and the ability to sacrifice and regrow their tails.