From ScienceDaily:
In nature, plants engage in a never-ending battle to avoid being eaten. Unable to run away, plant species have evolved defenses to deter herbivores; they have spines, produce nasty chemicals, or grow tough leaves that are difficult to chew. For years, scientists have assumed that herbivores and plants are locked into evolutionary competition in which a plant evolves a defense, the herbivore evolves a workaround, and so on.
New research led by the University of Utah challenges this paradigm of an evolutionary arms race.
The study analyzed multiple species of Inga, a genus of tropical trees that produces defensive chemicals, and their various insect herbivores. The researchers found that closely-related plants evolved very different defensive traits. Additionally, their analysis revealed that herbivores may drive evolution of plant defenses, but may not show coevolutionary adaptations. Instead, they may ‘chase’ plants based on the herbivore’s own traits at the time they encounter a new host. Paper. (paywall) – María-José Endara, Phyllis D. Coley, Gabrielle Ghabash, James A. Nicholls, Kyle G. Dexter, David A. Donoso, Graham N. Stone, R. Toby Pennington, Thomas A. Kursar. Coevolutionary arms race versus host defense chase in a tropical herbivore–plant system. Proceedings of the National Academy of Sciences, 2017; 201707727 DOI: 10.1073/pnas.1707727114 More.
In short, life forms often do different things, even if they are closely related. And where does the information for that level of complex adaptation come from?
Evolution is a history of life, not an illustration of textbook Darwinism. That’s possibly why we are hearing so much from the Fix doubters people these days.
See also: What the fossils told us in their own words