Behind the Z

The wonderous evolution of the mysterious Box-Fish

Part 3 : Oddballs

 

 

The family Ostraciidae, to wich the boxfish belongs, is part of the order Tetraodontiformes. The name comes from the latin tetra, meaning four, odous, meaning tooth, and forma, meaning form, because these fish have four tooth-like bones in their "beak". The phylogenetic relations of the Tetraodontiformes (meaning, how are they all related, and who came first, etc.) are still debated to this day. However, it is common to find rather strange forms in this order.

The ocean sunfish (Mola mola) is probably one of the most extreme examples of this. Other members of the order include the pufferfish, the filefish and the triggerfish. Most of these families are found near coral reefs. This could explain their high morphological plasticity, since coral fish are know for bright colors and particular morphology, which may not always be streamlined, since they do not often swim in open water.

In addition to their peculiar appearance, most of the families of this order are incapable of lateral flexion, and so, unlike the majority of fish, can move only with the help of their flippers. This makes their movements slow, but it is very precise.

The wide variety of unconventional features found in Tetraodontiformes can explain why the box-fish could acquire such a strange shape, since it seems its order does have a predisposition for morphological mutations. But what did drive this change ?

Did the corals where the boxfish appeared have square caves ? Was there a reproductive advantage to being square ? Was it attractive to the opposite sex ? Did it make it harder for predators to identify them as prey, giving them extra protection ? Did it make it inconspicuous to its own prey ? I didn't know yet, but was determined to find out the truth.