People who are living in a tundra type of ecosystem eat fishes and berries, use thick-walled shelter houses, and wear clothing that is made up of wool. Individuals living in deserts eat plant roots and low-protein food, lived in houses made of mud, and wear loose cotton clothing. In tropical rainforests, people eat a variety of plant and animal food, live in houses made of trees ,and most of them wear clothing made from natural fibers. A product that can be invented is a clothing that have built in heat pads which can be used for people living in a tundra ecosystem.