Orthogenesis, also known as orthogenetic evolution, progressive evolution, evolutionary progress, or progressionism, is the biological hypothesis that organisms have an innate tendency to evolve in a definite direction towards some goal (teleology) due to some internal mechanism or "driving force".

What is orthogenesis example?

157) stated that: “The most widely cited example of orthogenesis, in any sense of the word, is the evolution of the horse.” The problem with depicting fossil horses as orthogenetic is that, by the early twentieth century, paleontologists understood that, rather than a simple, straight-line sequence (Fig.

How does macroevolution occur?

Macroevolution refers to evolution of groups larger than an individual species. The history of life, on a grand scale. ... The basic evolutionary mechanisms — mutation, migration, genetic drift, and natural selection — can produce major evolutionary change if given enough time.