Principal Component Analysis (PCA) biplot based on fatty acid profiles (in % of NL-FA or PL-FA). Each dot represents an individual, positioned according to its coordinates on the first two principal components. Colors display the lipid fractions (NL = neutral lipids in yellow, PL = polar lipid in blue), shapes display the species (circle = Sardinella aurita; square = Sardinella maderensis), and size display the tissue type (smaller points = Gonad; larger points = Muscle). Arrows represent the most contributive variable fatty acids to the PCA axes (cos² > 0.35), with their orientation and length indicating their direction and strength of contribution to each dimension.