CANNIBALISTIC and willing to fight to the bitter end under the cover of darkness: Lysmata amboinensis shrimp have a brutally romantic side. They are so hell-bent on living in pairs that when placed in groups of three or four, they attack their peers until just one couple remains alive.
Each 6-centimetre-long cleaner shrimp is both male and female, but cannot self-fertilise, so needs a mate. Coupling up means they waste no energy on finding partners. Intense competition for food makes them aggressive to the point of killing off other shrimp that threaten their livelihood, with the exception of their mating…
