Answer to Question 1
The olfactory sense is very keen. The nose can detect extremely low concentrations of substances. There are only four basic tastes. Therefore the sense of smell is much keener than the sense of taste.
Answer to Question 2
Canada's extreme cold makes it possible only to grow crops in the south. In the southern region, long day light hours in the summer aid in the growth of crops. Farther to the north, the ground stays frozen most of the time and makes agriculture impossible. Canada stretches from the Pacific to the Atlantic Oceans as well as the Arctic Ocean in the north. Fish is abundant here.
Spectral sensitivity of the human cone opsins
Culture and sensitivity
Activation of the Primary Gustatory Cortex by Taste Stimuli
Papillae and Taste Buds
The Pleasure of Taste
Ecological sensitivity to climate change