As different species evolved, it can be seen that those pressures influenced how their cutaneous senses developed through the changes and sensory adaptation. In different climates and situations, one would need to adapt in order to survive. Ex. Someone who works in construction or gardening would develop callouses from the pressure of the tools they use.
They are different because a forensic chemist studies and tests chemicals and drugs and a forensic toxicologist studies poisons with criminal justice cases
