Question: Interested in exploring the genetic pathways that lead to neurological issues, you want to see if recessive mutations which generate too many neurons (tm) in flies - which many causes autistic like symptoms are in the same gene as mutations that generate too few neurons (tf) - intellectual diabilities. You cross a true-breeding homozygous tm/tm fly to a homozygous too few neuron fly tf/tf. What resulting phenotype in all progeny would tell these mutations are in different genes?