Why still humans have hair on body ?

Hair is important for maintaining skin health, as each hair follicle has blood vessels, nerves, and fat around it. Hair follicles are rich in stem cells that promote healing of the skin — helpful if you have a cut or wound. Hair also keeps a person warm and protects the skin from sun damage.

Explanation:

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Explanation:

Humans have hair on their bodies to prevent infections from entering the body. Lets take nose hair for example, while you breathe in and out threw your nose, any airborne virus may be caught and tangles in your nose hair, thus making it near impossible to enter your body, it is still possible though to enter the body.

Hair is important for maintaining skin health, as each hair follicle has blood vessels, nerves, and fat around it. Hair follicles are rich in stem cells that promote healing of the skin — helpful if you have a cut or wound. Hair also keeps a person warm and protects the skin from sun damage

While humans have developed clothing and other means of keeping warm, the hair found on the head serves primarily as a source of heat insulation and cooling (when sweat evaporates from soaked hair) as well as protection from ultra-violet radiation exposure. The function of hair in other locations is debated.

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affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.