Elemental reorganization after exposure to extreme resource pulses: Material implications of a blood meal in ticks

Abstract Animals must maintain elemental homeostasis while assimilating resources whose chemical composition differs from their own. Blood feeding represents an extreme example of this challenge because ticks ingest a large, discrete pulse of host‐derived material during a single meal. Here, we quantified the multielement composition (ionome) of two medically important tick species, Amblyomma americanum and Dermacentor variabilis , before and after blood feeding and compared these states with host blood. To our knowledge, this is the first whole‐ionome analysis of a blood‐feeding arthropod. Elemental data were expressed as log compositional coordinates to preserve relationships among elements within the measured ionome. Blood feeding significantly reorganized overall ionomic composition, and the first two principal components accounted for 67.1% of the total variation. The dominant axis contrasted relatively greater allocation to Ca, Sr, Mg, Ba, Zn and P with greater allocation to Fe and S, whereas secondary variation was associated primarily with K, Na, Cu and Mg. Despite the large influx of host material, fed ticks remained compositionally distinct from blood, and the magnitude of tick–blood imbalance differed substantially among elements. These findings demonstrate that blood feeding produces coordinated, element‐specific reorganization rather than passive convergence toward host composition. More broadly, ionomic analysis provides a framework for examining how consumers maintain elemental organization while assimilating large or chemically mismatched resource pulses.