The basic unit of macro-evolution is SPECIE. Macro-evolution refers to the theory of evolution in which changes that occur at or above the level of specie recognizes the need to better understand the patterns and processes which operate at the specie and higher levels within a hierarchical framework. Macro evolution is an evolutionary phenomenon, which can include any of the following: origination of new designs, large scale events such as extinction, broad trend and major transitions. <span />
As human has about 350 olfactory receptors and subtypes work in various conditions allowing us to sense about 10,000 doors. All senses of smell and tastes merge at the back of the throat.
As you taste something before smelling it the smell lingers on inside in the nose which makes you smell it. As both the smell and taste are chemoreceptors which means both have chemically same sensing environments.
In addition, the division of taste receptors within the nose coordinate with activities, although humans can distinguish between the tastes from the smells of the objects.
Working together to create a perception of flavor through the nasal passage.