Speciation is the formation of a new species from an existing one. A species is a group of organisms with similar characteristics that can interbreed to produce fertile offspring.All the alleles of all the genes in an interbreeding population make up its gene pool. While individuals can breed freely, alleles are shared throughout the gene pool and the population stays as one species.Speciation happens when part of a population becomes reproductively isolated, so that gene flow between the groups stops. The process is:1. A population is split into two or more groups that no longer interbreed. The barrier may be geographical, or it may be a difference in behaviour, timing of breeding or habitat.2. Each group now has its own separate gene pool.3. Different mutations arise in each group.4. The groups may experience different selection pressures, so natural selection favours different alleles in each. Chance changes in allele frequency (genetic drift) also have a bigger effect in small groups.5. Over many generations, the allele frequencies of the groups become so different that they change in phenotype, behaviour or physiology.6. Eventually, even if the groups meet again, they can no longer interbreed to produce fertile offspring. They are now separate species.
Speciation is the link between natural selection and the huge diversity of life. It is usually slow, taking thousands of generations, but it can be faster in organisms with short generation times or when isolation happens suddenly.
Speciation is the link between natural selection and the huge diversity of life. It is usually slow, taking thousands of generations, but it can be faster in organisms with short generation times or when isolation happens suddenly.