Genetic variation can<span> be </span>caused<span> by </span>mutation<span> (which </span>can<span> 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).</span>
Answer:
Energy is gained by consuming food
Energy is lost due to: The whole organism not being eaten (skeleton and fur left behind). Not all the food being digested – some passes out of the animal in excretion or egestion . Energy being lost as heat in respiration and therefore not being passed onto the next level.