Marine biologists investigated the effect of microplastic exposure on the metabolic activity of juvenile shore crabs (Carcinus maenas).
The oxygen consumption rates of 151515 juvenile crabs incubated in pristine, filtered seawater were measured (n1=15n_1 = 15n1=15). A second group of 151515 juvenile crabs was incubated in seawater contaminated with polystyrene microplastics (n2=15n_2 = 15n2=15).
The mean oxygen consumption rates (in μmol O2 g−1h−1\mu\text{mol O}_2\text{ g}^{-1}\text{h}^{-1}μmol O2 g−1h−1) and standard deviations for the two groups were recorded:
Identify the appropriate statistical test to compare the means of these two independent groups, and calculate the degrees of freedom (df\text{df}df) for this test.
The statistical test was performed, yielding a ppp-value of p<0.001p < 0.001p<0.001. Using the words probability, chance, and significant, draw a scientific conclusion from this result.
