URGENT: A fungus kills 75% of the plant life in tropical areas such as Florida, Mexico, Central America, and the Bahamas. These areas include plants that do not go into a dormancy, like in New England, and a significant percentage of global rain forests. Would might be the global result as it relates to: photosynthesis rate, amount of atmospheric carbon dioxide, and ecosystem balance.

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?