Speciation can occur by polyploidy. My understanding of the process is as follows:
'polyploidy is when the number of chromosomes in an organism's cell doubles. This means that the organism has more chromosomes than other individuals of the same species, meaning it cannot mate with other individuals. The polyploidy organism then evolves, eventually leading to it becoming a separate species'.
I realise this may not be exactly correct. Is someone able to provide a better description of speciation by polyploidy?