During the nineteenth century, biologists knew that South America and Africa contained similar fossils. These fossils led them to believe that a temporary land
bridge between South America and Africa allowed ancient species to move
between both continents. In the twentieth century, evidence showed that South
America and Africa were once part of the same larger continent and that there
were no land bridges between them. How should biologists respond to the new
geological finding?

Buuy which of the following did you include in your response? organs perform specific functions in the body to keep it alive. organelles perform specific functions in cells to keep them alive. done

The “ecological footprint” left by a citizen of a developed nation is about four times larger than that left by a citizen of a developing nation. why is this the case?

Female luna moths (actias luna) attract males by emitting chemical signals that spread through the air. a male hundreds of meters away can detect these molecules and fly toward their source. the sensory organs responsible for this behavior are the comblike antennae visible in the photograph shown here. each filament of an antenna is equipped with thousands of receptor cells that detect the sex attractant. based on what you learned in this chapter, propose a hypothesis to account for the ability of the male moth to detect a specific molecule in the presence of many other molecules in the air. what predictions does your hypothesis make? design an experiment to test one of these predictions.