When a scientist examined museum specimens of a particular moth species, she noticed that the variation in color was distributed as shown in the first graph. She was surprised because her data from current collections indicated the distribution of colors shown in the second graph. Which hypothesis about the cause of this shift in the range of genetic variation is the most likely to be supported by examination of the distribution of colors in a collection assembled at a time between that of the collection of the museum specimens and her current specimens?
◦ The bark of the tree on which moths landed became darker over time.
◦ Darker moths were more likely to survive and have offspring over time.
◦ Darker moths tend to lay more eggs than light moths.
◦ Birds prefer to eat lighter moths rather than darker moths.
A number of tree species can be interconnected by mycorrhizal fungi in the forests of British Columb
Foliage height diversity and bird species diversity (data from MacArthur and MacArthur 1961).
Some threatened and endangered species