Speciation is the evolutionary process by which new distinct species arise in evolutionary systems. A species is a reproductively isolated, independent evolutionary unit which occupies a certain niche. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages. In the course of evolution, a lineage of a species can split into two or more. The branching or bifurcation points in the phylogenetic tree mark the speciation events, where a new species emerges. A main reason for speciation in biology is geographical and reproductive isolation.
The major cause of speciation in biological systems is geographical separation or isolation, the four major types of speciation in nature are based on the extent to which speciating populations are geographically isolated from one another: allopatric (very strong), peripatric (strong), parapatric (weak), and sympatric (zero). Allopatric speciation involves barrier formation or complete habitat fragmentation, peripatric speciation a small niche at the periphery of the system, parapatric speciation a new niche connected to the system, and sympatric speciation a new niche inside the population.
The major cause of speciation in economic systems is technological isolation or innovation. A new technology can create whole new markets and new "ecosystems".
- Wikipedia entry for Speciation
- A seminal paper from John Maynard Smith on speciation, touching upon the dogma that speciation requires geographical separation Disruptive selection, polymorphism and sympatric speciation