How do species interactions result in a co-evolutionary arms race? Provide examples that aren’t from the book.
As organisms interact, it often occurs that populations will not coexist peacefully. In competitive, consumptive and parasitic relationships especially, an individual’s wellbeing is often decided by these interactions. Because of this, populations evolve overtime to become more efficient and competitive in these interactions. In competition, the population with the greatest ability to harvest the necessary resource will thrive, while other less able organisms will not receive the resource. In consumptive and parasitic relationships, the organisms with defenses against the predator or parasite are more likely to survive while some consumers may have traits that make them better at catching, finding or digesting their prey over others.
A co-evolutionary arms race occurs when populations on opposing sides of these relationships adapt over time and alter the balance of their interactions. One species may become more competitive at harvesting a resource over another over time, or a population may develop defenses against a parasite that has been devastating in the past. The development of these adaptations, whether they are physical or behavioral, creates an arms race between the two populations opposing each other in these relationships.
An example of this would be the ways in which different tree species compete for sunlight. In most cases, the tallest tree will receive the most sunlight, a necessary resource for photosynthesis. Because of this, populations will evolve over time to grow taller and stronger than the surrounding tree species. Growth and strength would be considered the desirable trait that is continually developed over time to make the species more competitive for the resource of sunlight.