What are the energy saving
techniques used by the
Class Chondrichthyes?

Chondrichthyes characteristics include a cartilaginous skeleton, lack of a swim bladder, lipid storage restricted to the liver, unique hematopoietic organs, and bacteremia in clinically normal individuals. Variable reproductive strategies are employed throughout this vertebrate class.

Explanation:

✿   this landform has a high elevation and a high relief

✿   this landform is a mountain

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).