Question

people who lost all or most of your sense of smell have a shorter life expectancy than people with normal sense of smell. How might your sense of smell help keep you alive? Why do you think animals evolved to be able to smell things?

( Short answer) and typed would be helpful

Answer 1

The sense of smell relies on the regeneration capacity of the stem cells. Stem cells are the cells from which the other cells develop showing that there is other existing problem with health. Sense of smell is also linked to the key parts of the central nervous system. Loss of smell may also be indicator of early symptom of neurodegenerative diseases such as dementia,alzheimer's and parkinson's disease.

University of Chicago researchers conducted a research where in 3,005 participants were given the three minute smell test . They had to sniff and identify five odours ranging from fish, orange,leather,rose and peppermint . They were classified as below-

Normosmic - people who could identify all five odours or missed just one.

Hyposmic - people who missed three or four odours.

Anosmic - people who missed to identify all five odours.

After five years of study , the results were --

40% of anosmic people were dead.

19% of hyposmic people were dead and

10% of normosic people were dead which explains the strong relation between sense of smell and life expectancy of people showing people who lost all or most of sense of smell have shorter life expectancy than people with normal sense of smell.

Sense of smell is essential for survival in most vertebrates . According to the habitat of animals ,the sense of smell varies. For example, in dolpins adapted to aquatic habitat has smaller subset of genes when compared to the other mammals. Differences in sensitivity of the smell in animals widely depend on the anatomy of the olfactory appartus.

Sense of smell plays an important part in animals. Many animals use phrenomes ( chemical communication) to attract mates ,to find prey,to mark territory,to protect themselves from predators etc..Dogs have extraordinary sense of smell making it use in police departments. Therefore, animals have evolved to be able to smell things as sense of smell is crucial in animal kingdom.