Marine Animals Chaetognatha as Bio-Indicators of Geophysical Activity

A study was done on the morphology of marine planktonic animals, Chaetognatha (arrow worms), taken during sea expeditions from the regions without the influence of geophysical activity, from shallow-water volcanic bays and deep-water geophysically active regions. It was discovered that among the chaetognaths from geophysically active regions there was a large number of animals (up to 95%) with morphological anomalies, while the animals from regions unaffected by geophysical activity had no structural abnormalities. Morphological deviations were investigated at the anatomical level using a hand magnifying glass and under a microscope, histological changes were also studied. There have been identified specific tissue anomalies which are not encountered under any other damaging effects of the environment. It is assumed that the observed anomalies of structure occur as a result of lysis of the muscle tissue under the influence of geophysical factors. Chaetognatha are characterized by high viability: anomalous specimens do not die and continue their livelihoods, so they can serve as biological indicators of increased geophysical activity in the region.