What describes the mechanisms of evolutionary change?

The mechanisms of evolutionary change are primarily described by the processes of vertical descent with modification and horizontal transfer. Vertical descent with modification refers to the way traits are passed down from one generation to the next with changes occurring over time, leading to adaptations and speciation. This process is fundamental to the theory of evolution, illustrating how species evolve and diverge from common ancestors.

Horizontal transfer, on the other hand, occurs when genetic material is exchanged between organisms in ways other than through traditional reproduction, such as through transformation, transduction, or conjugation. This mechanism is especially important in microbial populations and can introduce new genetic traits rapidly within a generation, influencing adaptability and evolution.

While the other choices include relevant concepts related to evolution, they do not fully encapsulate the main mechanisms of evolutionary change as effectively. Adaptation and speciation are outcomes of evolutionary mechanisms rather than mechanisms themselves, and while competitive exclusion can result from evolutionary processes, it is not a mechanism of change in the way that vertical descent and horizontal transfer are defined. Thus, the combination of vertical descent with modification and horizontal transfer provides a comprehensive description of the processes that drive evolutionary change.