Content
- What is asexual reproduction
- Types of Asexual Reproduction with Examples
- 1. Vegetative multiplication:
- 2. Parthenogenesis:
- 3. Gynogenesis:
- Asexual reproduction as a strategy for survival
- Animals with asexual reproduction
THE reproduction it is an essential practice for all living organisms, and it is one of the three vital functions that living beings possess. Without reproduction, all species would be doomed to extinction, although the presence of females and males is not always necessary for reproduction to occur. There is a reproductive strategy called asexual reproduction that is independent (in almost all cases) of sex.
In this PeritoAnimal article, we'll talk about asexual animals and their examples, starting with the description of the term "asexual reproduction". In addition, we will show some very varied examples of sexually reproducing organism.
What is asexual reproduction
Asexual reproduction is a reproductive strategy performed by certain animals and plants, in which the presence of two adult individuals of different sexes is not necessary. This type of strategy occurs when an individual produces offspring that are genetically identical to themselves. Sometimes we can find the term clonal reproduction, as it gives rise to clones of the parent.
Likewise, in this type of reproduction there are no germ cells (eggs or sperm) involved, with two exceptions, parthenogenesis and gynogenesis, which we will see below. instead they are somatic cells (those that make up all the tissues of the body) or bodily structures.
Types of Asexual Reproduction with Examples
There are many types and subtypes of asexual reproduction in animals, and if we include plants and bacteria, this list gets even longer. Next, we will show you the most studied asexual reproductive strategies of animals in the scientific world and, therefore, best known.
1. Vegetative multiplication:
THE budding is the typical asexual reproduction of marine sponges. It occurs when food particles accumulate in a specific type of cell in sponges. These cells insulate with a protective coating, creating a gemmula which is later expelled, giving rise to a new sponge.
Another type of vegetative reproduction is the budding. A group of cells on the animal's surface begin to grow to form a new individual, which may eventually separate or stick together and form a colony. This kind of reproduction takes place in hydras.
Some animals can reproduce by fragmentation. In this type of reproduction, an animal can split into one or more pieces and from each of these pieces a whole new individual develops.The most typical example can be seen in the life cycle of the starfish, because when they lose an arm, in addition to being able to regenerate it, this arm also forms a new individual, which is a clone of the original star.
2. Parthenogenesis:
As we said at the beginning, parthenogenesis requires an egg but not a sperm. The unfertilized egg can convert into a new organism. This type of asexual reproduction was first described in aphids, a type of insect.
3. Gynogenesis:
Gynogenesis is another type of uniparental reproduction. Eggs need a stimulus (the sperm) to develop an embryo, but it doesn't donate its genome. Therefore, the offspring is a clone of the mother. The sperm used need not be the same species as the mother, just a similar species. occurs in amphibians and teleosts.
Below, we show you an example of fragmentation reproduction in a starfish:
Asexual reproduction as a strategy for survival
Animals do not use this reproductive strategy as a normal method of reproduction, instead they only perform it in adverse times, such as when there are changes in the environment, extreme temperatures, drought, lack of males, high predation, etc.
Asexual reproduction reduces genetic variability, which can result in the disappearance of a colony, group or population of animals if sudden changes in the environment continue.
Animals with asexual reproduction
Many organisms use asexual reproduction to perpetuate species at less than ideal times. Below, we'll show you some examples.
- Spongilla alba: is a kind of fresh water sponge originating from the American continent, which can be reproduced by budding when the temperature reaches -10°C.
- cloudy glide: belongs to the phylum of flatworms or flattened worms. They live in fresh water and are distributed throughout Europe. These worms reproduce by fragmentation. If it is cut into several pieces, each of them becomes a new individual.
- Ambystoma altamirani: a salamander of mountain stream, as well as the other salamanders of the genus Ambystoma, can reproduce by gynogenesis. They are from Mexico.
- Ramphotyphlops braminus: the blind snake is originally from Asia and Africa, although it has been introduced in other continents. Is snake very small, less than 20 cm, and reproduces by parthenogenesis.
- hydra oligactis: hydras are a kind of jellyfish of fresh water that can reproduce by budding. It lives in temperate zones of the northern hemisphere.
In the following video, you can observe the regeneration after amputation of a flat worm, more specifically, of a cloudy glide:
If you want to read more articles similar to Asexual reproduction in animals, we recommend that you enter our Curiosities section of the animal world.