You discover a new species of butterfly that contains 120 different functional olfactory receptors in its genome. As in mammals, each neuron expresses only a single type of receptor. How many different odorants could this butterfly distinguish if each odorant binds three different odorant receptors?
Assume that normal humans have 380 olfactory receptors and that each odorant binds two different odorant receptors. Imagine a person born with a 10-fold reduction in active receptors due to mutations in 90% of the receptors. In this person, how many different active receptors would each odorant have to bind for the person to be capable of distinguishing at least the same number of odorants as a normal individual?
