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news & views Plate tectonics has revolutionized our understanding of the geological evolution of the Earth. This theory states that the Earth’s surface is a jigsaw puzzle of rigid lithospheric plates, and it is the movement of these plates relative to one another that is responsible for events such as mountain building, earthquakes and volcanism. The tectonic plates are the top boundary layer of the mantle convection system1. This implies that there should be a strong alignment between present-day plate movement at the Earth’s surface and flow direction in the Earth’s outermost mantle. Writing in Nature Geoscience, Martin-Short et al.2 present seismi