Frequent use of pesticides
Answer:
d. All of the above exemplify the difference between a population and an individual.
Explanation:
A population is a group of individuals of the same species that live in a particular geographical area and are able to interbreed. A population is described with respect to several features such as death and birth rates, age structure, density, dispersion, change in the population size due to density-dependent and density-independent factors and the survivorship curve.
These features are not exhibited by a particular individual. Natural selection also works at populations. The evolutionary forces act upon populations to change their allele and genotype frequencies. Therefore, populations are the unit of evolution and change genetically over time, not the individuals. Population ecology studies the size of a populations and the trends and causes of changes in the populations over time.
One explanation could be the differences in climate (environmental factors). The climate in northern Mexico could support the reproduction of the mosquito species, which is a vector of the dengue virus. Other environmental conditions that influence its endemicity could include living conditions and sanitation. The other possiblity could be that the people in the US have developed immunity for the disease, therefore, are unaffected even when infected by the virus.
A,C,D are the answers. I took Biology.