Animal reproduction

Author: Peter Berry
Date Of Creation: 11 February 2021
Update Date: 21 December 2024
Anonim
Animal reproduction Lions reproduction of2013
Video: Animal reproduction Lions reproduction of2013

Content

All living beings on the planet must reproduce to perpetuate the species. Despite this, not all succeed or not necessarily all individuals of a species reproduce. For example, animals that live in eusocieties are given a role within the group and only one or a few individuals reproduce. Lone animals, in turn, will seek and fight for their right to reproduce and perpetuate their own genes.

Another large group of animals performs another reproductive strategy, in which the presence of the opposite sex is not necessary to reproduce. We'll talk about them all in this PeritoAnimal article. Want to know more about animal breeding? Keep reading!


What is animal reproduction?

Reproduction in animals is a complex process of hormonal changes that cause physical and behavioral changes in individuals to achieve a single purpose: to produce offspring.

For this, the first change that must occur is sexual maturation of the animals. This fact occurs at a certain point in the life of each individual, depending on their species. It all starts with the establishment of the sexual organs and the formation of gametes, which is called spermatogenesis in males and oogenesis in females. After this episode, part of the animals' lives is focused on search for a partner to establish a bond that leads them to reproduce.

However, there are animals that, despite having these organs, at certain times and under specific conditions, do not use them. This is known as asexual reproduction in animals.


Types of animal reproduction

In nature there are several types of reproduction in animals. Each of them has definite characteristics that make them very different from each other. In general terms, we can say that the types of animal reproduction are:

  • Sexual reproduction in animals
  • Asexual reproduction in animals
  • Alternating reproduction in animals

Next, we'll talk and give examples of each of them.

Sexual reproduction in animals

Sexual reproduction in animals is characterized by having two individuals involved, one female and one male. The female will produce eggs formed by oogenesis in her ovaries. The male, in turn, will create sperm in his testicles, which are usually characterized by being small and having high mobility. These sperm have the function of fertilizing the egg and form a zygote that will gradually evolve to form a complete individual.


Fertilization can occur inside or outside the female's body, being known as internal or external fertilization, depending on the species.

Internal fertilization in animals

During internal fertilization, sperm pass through the female reproductive system in search of the egg. The female will then be able to develop the offspring within it, as with live-bearing animals, or on the outside. If embryonic development takes place outside the female body, we are talking about oviparous animals, which lay eggs.

External fertilization in animals

On the contrary, animals with external fertilization release their gametes into the environment (usually aquatic), both eggs and sperm, and fertilization takes place outside the body.

The most important feature of this type of reproduction is that the resulting individuals carry in their genome genetic material from both parents. Therefore, sexual reproduction increases the probability of survival of a species in the long term, thanks to the genetic variability it produces.

Asexual reproduction in animals

Asexual reproduction in animals is characterized by absence of another individual of the opposite sex. Therefore, the offspring is identical to the breeding individual.

Furthermore, asexual reproduction does not necessarily involve germ cells, that is, eggs and sperm; in most cases, they are somatic cells capable of dividing. Somatic cells are the normal cells in the body.

Types of Asexual Reproduction in Animals

Next, we will see that there are several types of asexual reproduction in animals:

  • gemmulation or gemmation: is the typical asexual reproduction of sea sponges. A specific type of cell accumulates food particles and, in the end, separates and creates a gene that gives rise to a new individual...
  • budding: In hydras, a specific type of cnidarian, asexual reproduction occurs by budding. On the surface of the animal, a certain group of cells begins to grow, forming a new individual that can separate or remain close to the original.
  • fragmentation: is one of the types of reproduction performed by animals such as starfish or planarians. Your body can be segmented into several parts, each of which gives rise to a new individual.
  • Parthenogenesis: in this type of asexual reproduction, a germ cell is involved, which is the egg. This, even if not fertilized, can develop and create a female individual identical to the mother.
  • Gynogenesis: this is a rare case of asexual reproduction, which only occurs in certain amphibians and bony fish. The male donates his sperm, but this is only used as a stimulus for egg development; he doesn't actually contribute his genetic material.

Animals with asexual reproduction

Some of the animals with asexual reproduction that we can find are the following:

  • Hydra
  • Wasps
  • Starfish
  • sea ​​anemones
  • sea ​​urchins
  • sea ​​cucumbers
  • sea ​​sponges
  • amoebas
  • salamanders

Alternate breeding in animals

Among animals, although not very common, we can also find alternate reproduction. During this reproductive strategy, the sexual and asexual reproduction are interspersed, though not necessarily.

This type of reproduction is very common in the plant world. In animals it is rare, but it can be seen in certain eusocieties, such as ants and bees, ie, in invertebrate animals. The alternative breeding strategy in animals will depend on each species.

If you want to read more articles similar to Animal reproduction, we recommend that you enter our Curiosities section of the animal world.