Zoologist: Horseflies are attracted to horizontally polarized light, which reflects off large, dark animals that they bite. This
may explain why zebras evolved vertical stripes—the stripes cancel the horizontal polarization of light and thus make zebras less attractive to horseflies. In order to assess the plausibility of the zoologist's hypothesis, it would be most helpful to know whether
A. any insects other than horseflies are attracted to horizontally polarized light.
B. the vertical stripes on zebras make it easier for any insects other than horseflies to see them.
C. animals that horseflies commonly bite have evolved other means of reducing the impact an frequency of those bites.
D. any biting insects other than horseflies are strongly attracted to zebras.
E. zebras' vertical stripes provide camouflage protection against certain large predators potentially very dangerous to zebras.
D. any biting insects other than horseflies are strongly attracted to zebras.
Explanation:
In order to assess the plausibility of the zoologist's hypothesis, it would be most helpful to know whether if any other insects other than the horseflies are strongly attracted to the Zebra. If other insects are attracted to the zebra, we can then try to research and see if these other insects also show tendencies to be attracted to horizontally polarized light before we can conclude on this hypothesis. The hypotheses will hold more strongly if the same phenomenon applies to other biting insects attracted to the Zebra.
The correct answer is absence of jaws. Lampreys and hagfish are in the class Agnatha, they are jaw-less fish. The members of the agantha class are probably the earliest vertebrates. Scientists have found fossils of agnathan species from the late Cambrian period that occurred 500 million years ago.