Evolution As Fact and Theory - Related Concepts and Terminology

Related Concepts and Terminology

To explain means to identify a mechanism that causes evolution, and to demonstrate the consequences of its operation. These consequences are then the general laws of evolution, of which any given system or organism is a particular outcome.

• "Proof" of a theory has different meanings in science. Proof exists in formal sciences, such as a mathematical proof where symbolic expressions can represent infinite sets and scientific laws having precise definitions and outcomes of the terms. Proof has other meanings as it descends from its Latin roots (provable, probable, probare L.) meaning to test. In this sense a proof is an inference to the best or most parsimonious explanation through a publicly verifiable demonstration (a test) of the factual (i.e., observed) and causal evidence from carefully controlled experiments. Gould argued that Charles Darwin's research, for example, pointed to the coordination of so many pieces of evidence that no other configuration other than his theory could offer a conceivable causal explanation of the facts. In this way natural selection and common ancestry has been proven. "The classical proof is the improvement of crops and livestock through artificial selection." Natural selection and other evolutionary theories are also represented in various mathematical proofs, such as the Price equation. To remain consistent with the philosophy of science, however, advancement of theory is only achieved through disproofs of hypotheses.
• "Models" are part of the scientific or inferential "tool-kit" that are constructed out of preexistent theory. Model-based science uses idealized structures or mathematical expressions to strategically create simpler representations of complex worldly systems. Models are designed to resemble the relevant aspects of hypothetical relations in the target systems under investigation.
• "Validation is a demonstration that a model within its domain of applicability possesses a satisfactory range of accuracy consistent with the intended application of the model." Models are used in simulation research. For example, evolutionary phylogeneticists run simulations to model the tree like branching process of lineages over time. In turn, this is used to understand the theory of phylogenetics and the methods used to test for relations among genes, species, or other evolutionary units.