The oak tree pathogen, Phytophthora ramorum, has migrated 650 km in 10 years. West Nile virus spread from New York State to 46 other states in 5 years. The difference in the rate of spread is probably related to
A) the lethality of each pathogen.
B) the mobility of their hosts.
C) the fact that viruses are very small.
D) innate resistance.
E) dormancy viability.

Question

Quizplus · Accepted Answer

The difference in the rate of spread is likely due to the mobility of their hosts. Phytophthora ramorum infects oak and other tree species, which are relatively immobile, while West Nile virus infects birds and mosquitoes, which are much more mobile and able to spread the virus over larger distances in a shorter period of time. The lethality, size, resistance, or dormancy viability of the pathogens are not directly related to their rate of spread.

The Oak Tree Pathogen, Phytophthora Ramorum, Has Migrated 650 Km