Is -2-(-7) a positive value

yes

Step-by-step explanation:

-2*(-7) = 14

yeah it is coz -2+7=+5 you see it's positive

the answer is; biodiversity resulting from few ancestors

adaptive radiation occurs when a population is subjected to a large natural environment with spatial ecological variations. the parts of the population in the different ecologies begin to adapt to their local environments. due to non-random mating across the large populations, this causes the different populations from the large population to speciate within their local environments. they, therefore, diverge to different species sharing a common ancestor.  

a reflection across the x axis and a 90 degree rotation left and right.