  Diffusiophoresis, which refers to the movement of entities driven by
gradients in the concentration of attractants, is observable in colloids and
chemotactic bacteria. We suggest that humans also exhibit diffusiophoresis when
they perceive concentration gradients in economic opportunities, social
connections, safety factors, and more. Consequently, we build upon the
Fisher-KPP reaction-diffusion model, which is foundational to human population
dynamics, to incorporate diffusiophoretic advection. Through simulations, we
demonstrate that diffusiophoresis can predict the emergence of population
hotspots from initially dispersed populations and can enable precise control
over inter- and intra-population segregation, a capability not achievable
through Fisher-KPP alone. This framework is particularly pertinent given the
anticipated impacts of climate change, which may result in significant human
displacement influenced by the diffusiophoretic movement of individuals in
response to concentration gradients in safety conditions.
