When an owl hears a sound, the sound will hit each of its ears at a different time because the separation between the ears results in a time delay. The neuronal stimuli triggered need to reach the audio processing centres of the brain simultaneously; *TBC

*continued;how would you design the neurones leading from the ears to the audio processing centre to ensure that the stimuli will reach it at the same time?We need to start by establishing that the signal from the ear that the sound reaches first needs to be delayed in some way relative to the other.There are three key ways that we can alter speed of neuronal transmission:axon diameter - a larger axon confers less resistance and therefore a greater speed of transmissionpresence of a myelin sheath - this allows for saltatory conduction and therefore faster transmissionlength of the neurone - a longer neurone will delay the speed of transmissionBased on this we can establish that for the neurone where we want the transmission time to be longer we need:no myelin sheath - this means that saltatory conduction cannot occura much narrower axon - this increases the overall resistance to the transmission of the action potentiala much longer neurone - if the audio centre is central in the brain, then in order to increase the length of the neurone we will have to loop it back and forth repeatedly on its journey.And for the neurone whose transmission time needs to be shorter:a myelin sheatha broader axonand a neurone that travels directly to the audio centre of the brain.