aquatic animals like squid Turtle sea horse

>For the open-source web proxy cache, see Squid cache; also see Squid (disambiguation) SQUIDs, or Superconducting Quantum Interference Devices, are used to measure extremely tiny magnetic fields; they are currently the most sensitive such devices (magnetometers) known, with noise levels as low as 3 fT·Hz−½. Some processes in animals produce very small magnetic fields (typically sized between a nanotesla and a microtesla (1000 nT) — a typical fridge magnet is one hundred microtesla), and SQUIDs are well suited to studying these. Magnetoencephalography (MEG), for example, uses measurements from an array of SQUIDs to make inferences about neural activity inside brains. Because SQUIDs can operate at acquisition rates much higher than the highest temporal frequency of interest in the signals emitted by the brain (kHz), MEG achieves good temporal resolution. Another application is the scanning SQUID microscope, which uses a SQUID immersed in liquid helium as the probe. The use of SQUIDs in oil prospecting, earthquake prediction and geothermal energy surveying is becoming more widespread as superconductor technology develops; they are also used as precision movement sensors in a variety of scientific applications, such as the detection of gravity waves. Four SQUIDs are currently employed on Gravity Probe B in order to test the limits of the theory of general relativity. See more at Wikipedia.org...

[ext Turtles are reptiles of the order Chelonia, most of whose body is shielded by a special bony or cartilagenous shell developed from their ribs. The term turtle is usually used for the aquatic species, though aquatic fresh-water turtles are also called terrapins. The term is sometimes used (esp. in North America) to refer to all members of the order, including tortoises, which are predominantly land-based. The order of Testudines includes both extant (living) and extinct species. About 300 species are alive today. Turtles are now highly endangered, largely due to beach development and over-hunting. See more at Wikipedia.org...]