Forsythia mermaids have a range of tails from 2-4 meters in length as a result of
genetic variation. Most mermaid tails are around 3 meters. On the reef they live on,
a new predator of the mermaid arrived and its quick speed meant only mermaids
who could maneuver quickly, those with longer tails, were able to survive. Over the
next few generations, what do you predict happened to the tail length of the
Forsythia mermaids?

Which of the following occurs most often in a population when genetic variation and overproduction are present? some organisms have a lower reproductive success than others. some organisms have a higher reproductive success than others. some organisms have no reproductive success. some organisms do not have genetic variation.

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?

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.