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These shrimp goby live in a symbiotic relationship with shrimps(they sharing same burrow). The shrimps are almost blind and need the goby to keep an eye out for predators. Shrimp goby needs a hiding place and benefits from living in the burrow excavated by the shrimp.
Goby in this video: Spotted shrimp goby (Amblyeleotris guttata).
https://youtu.be/jUL4d7YeVNE
3 minute long original footage compressed(fast forward) in 35sec.
Filmed at Ambon, Indonesia / Canon 7D, 100mm
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I’m sure many people already know about relationship this shrimp and goby.
But I’m still very curious to know how they actually decide to pair up in the first place?