Researchers wanted to determine if pesticide X was effective…

Researchers wanted to determine if pesticide X was effective at killing grasshoppers that typically invade cornfields. Two ten-acre cornfields located 1 mile apart were chosen. The cornfield to the west was sprayed only with water. The cornfield on the east received the same amount of water with a 10% solution of pesticide X. Grasshopper abundance was measured in the fields every week for 10 weeks.  The results were: West field – the number of grasshoppers doubled East field – the number of grasshoppers declined by 50% What was the independent variable in the above experiment?

Deep in the ocean are communities nestled around hydrotherma…

Deep in the ocean are communities nestled around hydrothermal vents where super-heated water springs from the bottom of the ocean.  No sunlight ever penetrates to these deep regions. The water from the vents is rich in dissolved minerals such as hydrogen sulfide which supports a large population of chemoautotrophic bacteria that use sulfur compounds to form organic matter by chemosynthesis.  These communities frequently have worms, clams, shrimp, and many other organisms clustered together. In hydrothermal vent communities, we would not expect to find ___.