What theory did Charles Darwin introduce that relates to animal behavior?

Charles Darwin introduced the theory of evolution, which fundamentally explains how species change over time through the process of descent with modification. This concept is pivotal in understanding animal behavior because it provides a framework for examining how certain traits, including behaviors, can enhance survival and reproduction in different environments.

The theory of evolution posits that favorable variations are more likely to be preserved and passed on to future generations. This directly relates to behaviors that may improve an individual's fitness in its environment, leading to the gradual adaptation and development of certain behavioral traits within populations. Consequently, the study of evolution allows researchers and practitioners in veterinary fields to better understand not just physical traits, but also the behavioral adaptations of animals influenced by their environments and social structures.

Other theories mentioned do not pertain to animal behavior in a biological context. The theory of gravity and the theory of relativity are central to physics, dealing with forces and the nature of space-time, respectively, and do not encompass biological concepts or the behaviors of animals as influenced by evolutionary processes. The connection between the theory of natural selection, which is often considered a mechanism of evolution, is also integral. However, the broader label of "theory of evolution" is more encompassing and captures the overall idea that includes various aspects of