How does meiosis contribute to genetic variation in a speciation?

1 Answer
May 19, 2017

Meiosis is recognized as a process that contributes to genetic variation.

Here's a brief overview: There are two divisions that occur during the entire process of meiosis, ending in haploid cells. You start with a diploid (2n) cell, and end with 4 (n) haploids. There are two phases, Meiosis I and Meiosis II.

The genetic variation part: During Prophase I of Meiosis I, a unique event occurs, called "crossing over".

The replicated homologous pairs of chromosomes join together during "synapsis". Here, sections of chromosomes are exchanged. The end result includes chromosomes with genes from both parents, which increases genetic variation.

The process of synapsis and crossing over only occurs in sexual reproduction (meiosis).

You can see here that the resulting chromosomes have mixed up genes, compared to the completely paternal and completely maternal chromosomes before the process occured.