Metabolic adaptations in a range-expanding arthropod

Area of Science:

• Evolutionary Biology
• Physiology
• Metabolomics

Background:

• Life-history evolution during range expansions lacks mechanistic understanding.
• Physiological processes underlying range shifts require investigation.

Purpose of the Study:

• To explore physiological changes during the range expansion of the two-spotted spider mite (Tetranychus urticae).
• To investigate the metabolomic basis of adaptation in expanding populations.

Main Methods:

• Sampling mite populations along a latitudinal gradient from range core to edge.
• Rearing mites under common garden conditions for two generations.
• Utilizing gas chromatography-mass spectrometry (GC-MS) for metabolic profiling.

Main Results:

• Metabolic profiles showed gradual differentiation along the latitudinal gradient.
• Changes indicated (epi)genetic alterations in the metabolome linked to range expansion.
• No shifts in energetic metabolism were observed; instead, differential amino acid use was prominent.
• Northern, more dispersive populations exhibited lower concentrations of essential and nonessential amino acids.

Conclusions:

• Range expansion in Tetranychus urticae is associated with metabolomic differentiation.
• Adaptation involves altered amino acid metabolism, potentially downregulating protein synthesis pathways in expanding populations.