We are repeatedly warned against newer zoonotic diseases (transferred from non-human animals to humans) in future, resulting from our rapid insurgence into natural ecosystems. How/Why do these zoonotic infections arise? Where will they come next? Such understanding will be far from complete unless we start tracking myriad evolutionary interactions of immunity, ecology and life-history of disease carrying animals in their natural habitat. We certainly need more experiments to bridge the wide gap between ecology and evolution of these species, immune strategies & underlying molecular-cellular and physiological processes.
The new review-Perspective led by @srijan_seal captures this very essence quite nicely. Do give a read 
Welcome to Evolutionary Immunology Lab at Ashoka University 