Please explain the concept of large scale evolution

Priya sarda Best Answer

Large scale evolution is commonly known as Macro evolution. Macroevolution refers to the concept of large-scale evolution that occurs at the level of species and above. Macroevolution is evolution on the grand scale: the term refers to events above the species level; the origin of a new higher group, such as the mammals, would be an example of a macroevolutionary event. Macroevolution has mainly been studied morphologically, because we have more taxonomic and fossil evidence than for other kinds of characters, such as physiology or chromosomes. According to the neo-Darwinian theory of macroevolution, major evolutionary transitions such as the origin of mammals from reptiles - well documented in the fossil record - occur in gradual adaptive stages. However, macroevolution may proceed by developmental macromutations as well as by gradual adaptation. Macroevolution can be contrasted with microevolution: evolutionary changes on the small scale, such as changes in gene frequencies within a population. A major issue relating to many controversies in evolutionary biology is the extent to which macroevolutionary changes can be explained by microevolutionary processes Macroevolution can be used to describe the differences between two closely related but distinct species, such as the Asian Elephant and the African Elephant, which cannot mate due to the barriers imposed by reproductive isolation. This is the process of speciation, which can be driven by a number of different mechanisms. Additionally, macroevolution can describe differences between that organisms belonging to larger clades of organisms, for example the different taxonomic groups within the primates. The term macroevolution can also be used to explain the shared common ancestry between all living organisms, a concept known as Universal Common Descent. This describes the derivation of all existent and extinct life forms from a single origin, and includes evolutionary milestones such as the origins of plants, mammals, reptiles, birds, fish, non-avian dinosaurs and more.