D debilitated- lacking strength, weekend deficiency- a lack of something needed or necessary demographers- experts who study the size and other measurements of human population descendants- people who come from or descend from ancestors long line of family members diameter- a straight line passing through the center of a circle dietary- related to a diet of foods to be eaten diminishing- to become smaller divination- an act undertaken to foresee or foretell future events or find hidden, supernatural powers dome-shaped- something with a round roof domesticated- to train a wild animal to live with people durable- able to last a long time