Which of the following is an example of adaptive radiation? a. one population of squirrels becomes two separate species over a long time. b. one population of lizards leads to 15 separate species over a short time. c. one species of birds becomes better suited to its environment over time. d. two species of fish begin to breed with each other.

In what layer of the sun is energy transfers between atoms

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?

If you want to double a batch of brownies you must have double the ingredients before you start cooking similarity a cell must double its contents including its dna prior to dividing