What is self-fertilization and how does it differ from cross-fertilization?

Self-fertilisation is the fusion of male and female gametes from the same individual, unlike cross-fertilisation which involves two different individuals.

Self-fertilisation, also known as selfing, is a type of sexual reproduction where the male and female gametes produced by a single organism fuse to form a zygote. This process is common in many plant species and some animal species, where an individual can produce both types of gametes. The offspring produced through self-fertilisation are genetically identical to the parent, barring any mutations, as they receive the same set of genes from a single parent.

On the other hand, cross-fertilisation, also known as outcrossing, involves the fusion of male and female gametes from two different individuals. This is the most common form of sexual reproduction in animals and also occurs in many plant species. The offspring produced through cross-fertilisation are genetically diverse, as they receive a mix of genes from both parents. This genetic diversity can be beneficial for the survival of the species, as it can lead to individuals with different traits that may be advantageous in different environments or situations.

The main difference between self-fertilisation and cross-fertilisation lies in the source of the gametes and the resulting genetic diversity. Self-fertilisation involves gametes from the same individual and results in genetically identical offspring, while cross-fertilisation involves gametes from two different individuals and results in genetically diverse offspring. This difference can have significant implications for the evolution and survival of species. For example, while self-fertilisation can be a quick and efficient way to reproduce, it can also lead to a lack of genetic diversity and potential vulnerability to environmental changes or diseases. Conversely, while cross-fertilisation can lead to greater genetic diversity and potential adaptability, it can also be more complex and require more energy and resources.