Shear legs to the gin pole, derrick and tripod (lifting device). Shears are an A-frame of any kind of material such as timbers or metal, the feet resting on or in the ground or on a solid surface which will not let them move and the top held in place with guy-wires or guy ropes simply called "guys". Shear legs only need two guys whereas a gin pole needs at least three. The U. S. Army Field Manual FM 5-125 gives detailed instruction on how to rig shears. Fixed shear legs are most commonly found on floating cranes known as floating sheerlegs.
Crown-of-thorns starfish starfish larvae in experimental studies gave support for a mechanism for starfish outbreaks: increased terrestrial runoff → increased nutrients denser phytoplankton↑→ better larval survival → increased starfish populations There have been further conformations of these connections, however research by Olson (1987), Kaufmann (2002), and Byrne (2016) suggests terrestrial runoff has little or no impact on larval survival. The conflicting data describing the negligible role of terrestrial agricultural runoff has been described as "an inconvenient study". There is also a flow-on effect in that where there are large starfish populations producing large numbers of larvae, there is likely to be heavy