Phoresy Animals often have to move from place to place to obtain resources. Most animals do so using their own physical effort, but animals of certain species may not be able to transport themselves efficiently in order to access the resources they need. These animals may make use of another animal species to transport them, without causing any injury to the other species. This relationship is known as phoresy. Phoresy, which is a temporary relationship, benefits the passenger species and causes little or no harm to the species doing the transporting.