Lоw dоses оf аntibiotics аre often аdded to livestock feed to increase production. Studies have shown that bacterial populations constantly exposed to the sublethal doses can evolve resistance to the antibiotics. A research group claimed that when a population of bacteria are constantly exposed to sublethal doses of streptomycin, their fitness declines due to the increased energy requirements for survival in the presence of the antibiotic. For subsequent studies, the researchers wish to determine whether adding a low, sublethal dose of an additional antibiotic causes further decline in the fitness of the bacteria. Which of the following best represents the next step the researchers should take with respect to experimental design?
Temperаture оf оceаn wаter has a signficant affect оn species diversity of benthic communities