How do we select species for conservation?

Abstract

THE LIVING ORGANISMS ON EARTH CAN ONLY BE SAVED (TO SOME DEGREE) WITH RATIONAL AND COST-EFFICIENT METHODS. ONE APPROACH IS TO CONSIDER GENETIC DIVERSITY WHEN SELECTING SPECIES FOR CONSERVATION MEASURES. THE ACTUAL GENETIC DIVERSITY IS DIFFICULT TO ESTIMATE IN MOST CASES, BUT CAN BE ASSUMED TO CORRESOND WITH THE MORPHOLOGICAL, ANATOMICAL OR MOLECULAR DIVERSITY OF THE ORGANISMS. THEREFORE, CLADISTIC ANALYSES BASED ON SUCH DATA FORM A GOOD BASIS FOR MARKING PRIORITY LISTS AMONG SPECIES IN MONOPHYLETIC GROUPS. SPECIES SHOULD BE SELECTED IN AN ORDER THAT ALWAYS MAXIMISES THE NUMBER OF CHARACTER STATE TRANSFORMATIONS OR STEPS COVERED ON A CLADOGRAM, FOR A GIVEN NUMBER OF SPECIES SELECTED. AFTER A FIRST PRIORITY LIST WITH ALL SPECIES HAS BEEN ESTABLISHED IN THIS WAY, SPECIES THAT CAN BE ASSUMED TO SURVIVE WITHOUT FURTHER MEASURES SHOULD AT PRESENT BE EXCLUDED FROM FURTHER CONSERVATION ACTIONS. WHEN THE FINAL SELECTION AND PRIORITY ORDER OF SPECIES HAS BEEN THUS ACHIEVED, THE AREAS NECESSARY TO PROTECT AS MANY OF THESE SPECIES AS IS POLITICALLY POSSIBLE SHOULD BE SELECTED IN AN OPTIMAL WAY. NEITHER SELECTION OF SPECIES NOR CONSERVATION ACTIONS CAN BE PERFORMED ON A NATIONAL BASIS BECAUSE THE DISTRIBUTIONS OF SPECIES AND HIGHER TAXA RARELY COINCIDE WITH NATIONAL BOUNDARIES. IN LARGE GROUPS (E.G., LARGER FAMILIES), APPROXIMATIONS CAN BE MADE AT HIGHER TAXONOMIC LEVELS WITH THE SAME METHODS AS AT THE SPECIES LEVEL TO ESTABLISH PRIORITY ORDERS FOR GENERA OR OTHER TAXONOMIC UNITS. IF LARGE OVERVIEW ANALYSES BASED ON SELECTED SPECIES ARE MADE IN LESS WELL KNOWN GROUPS OF ORGANISMS, IT IS SUGGESTED THAT THE CLADE (S) WHERE THE GREATEST VARIATION IN THE GROUP IS FOUND IS LIKELY TO INCLUDE A RELATIVELY LARGE PROPORTION OF THE TOTAL GENETIC VARIATION WITHIN THE ORGANISM GROUP. THIS CLADE SHOULD THUS BE GIVEN A RELATIVELY HIGH PRIORITY IN THE CONSERVATION WORK.