In this model, cell clusters can “feel” farther beyond their surrounding environment in the human body by acting as a collective, shown here “reaching out” with the red indicating the spatial distribution of the collagen deformation over a layer of stiff tissue. WashU researchers share details on this emergent property in the journal PNAS. Credit: Pathak lab The fairy tale of the princess and the pea tells of a young royal so sensitive she could detect a tiny pea hidden beneath many mattresses.