Sexual reproduction occurs when living organisms combine genetic information from two different types. These types are referred to as “sexes.” For most high-level organism, this occurs between two genders. The male gender produces a mobile gamete which travels to fuse with a stationary gamete that is produced by the female gender.
Gametes are germ cells that are able to unit with germ cells from the opposite gender. Some may refer to them as “sex cells” or “reproductive cells.” For humans, the male gamete would be sperm cells and the female gamete would be egg cells.
The primary advantage of sexual reproduction is that it encourages the survival of a species. Whether discussing people, plants, or animals, mates are attracted to one another based on a hormonal perception of superiority. There is a natural desire to mate with someone from the opposite gender with heterosexual attraction so that the best possible traits can be passed along to the future offspring.
The disadvantage of sexual reproduction is that outside influences can determine the viability of the offspring. In humans, for example, a failure for a mother to consume an adequate amount of folic acid is directly linked to neural tube birth defects. This defect occurs at the earliest stages of development, often when a woman doesn’t know she is pregnant, which means the folic acid must be consumed when attempting to conceive. About 3,000 children in the US are born with neural tube defects in the United States every year.
Here are some additional advantages and disadvantages of sexual reproduction to consider as well.
List of the Advantages of Sexual Reproduction
1. It creates genetic diversity within a species.
In asexual reproduction, a direct copy, a clone, is produced. This allows for reproduction to occur without a mate, but it also increases the chances of a mutation developing within the species. Should the wrong mutation occur, the entire species could eventually be wiped out.
Sexual reproduction prevents this issue from occurring because the genetic materials from two parents, not one, are used to produce an offspring. That prevents genetic bottlenecks from occurring.
2. There is a natural level of disease resistance throughout the species.
A greater level of genetic diversity allows for higher levels of natural disease resistance within a species. That is because the bacteria, parasites, and viruses which may affect the health of a species are unable to adapt to one specific genetic profile. There will always be disease, but genome diversity allows for the immune systems of people, plants, and animals to fight off the intrusions so a healthy life can be maintained.
3. Genetic variation can lead to evolutionary advancements.
Genetic variation incorporates a process that is similar to the “survival of the fittest” principles that Charles Darwin first introduced. Darwin suggested that the animals of a species that are best suited to their environment are the most likely to survive. Through sexual reproduction, those survivors pass on their traits to their offspring, which allows the species to begin to evolve on micro-levels, and potentially on macro-levels as well.
Even if evolution does not occur, sexual reproduction does offer the chance to screen out undesirable traits or genetics from a species. Many tests are available to determine the genetic status of people, plants, and animals. By identifying high-risk individuals and restricting their access to breeding, it is possible to eliminate certain poor genetic profiles.
These restrictions are not generally imposed on humans, but can be seen in other species, such as horses.
4. It is a rewarding experience.
Sexual reproduction makes those experiencing it feel good. It stimulates the pleasure centers of the brain so that more is wanted. This happens because sexual reproduction, especially in humans, releases dopamine. It can even be addictive, much like cocaine, because of how it affects the brain. It can act like a drug in more than one way.
Sexual reproduction can act as an antidepressant. The process of sexual reproduction can help to relieve pain. Vigorous sexual reproduction can even lead to temporary amnesia, but it can also improve personal memory.
In many ways, sexual reproduction is designed to be a rewarding experience. That encourages reproduction to occur so that the cycle of life can continue.
5. It can encourage the growth of brain cells.
In asexual reproduction, a parent essentially clones itself to create an offspring. Both are individuals, but copies of one another. In sexual reproduction, a 2010 finding by Princeton scientists discovered that sexually active creatures experience brain growth compared to creatures that are not sexually active.
Sexual activity increases the production of brain cells within the hippocampus. This is the area of the brain that manages memory. Larger cells and more connections form with a greater frequency of mating.
6. It improves health.
In humans, practicing sexual reproduction is directly linked to better health. Men who have sex 1-2 times per week, for example, have a lower risk of developing heart disease compared to men who have sex 1-2 times per month or less. At the same time, sexual activity can lower blood pressure and reduce the influence of cortisol, a stress hormone, on the body.
Sexual activity can also promote a stronger immune system, stronger muscles, and may even lower certain cancer risks.
One unique benefit of sexual reproduction is that it increases levels of oxytocin, which is often called the “love hormone.” Sexual activity increases the generosity people have when they are emotionally engaged with a mate.
List of the Disadvantages of Sexual Reproduction.
1. It takes time and energy to find a mate and reproduce.
In sexual reproduction, the two genders must find each other to be able to reproduce. It takes time and energy to locate a suitable mate with the preferred traits that are desired so that the offspring produced by the union can thrive. For some species, the process of mating is an all-encompassing task that requires a sole focus on the reproductive cycle until it is completed.
2. Reproduction through sexual means is uncertain.
Sexual reproduction is not a 100% successful method of creating offspring. Some chosen mates may be infertile. Others may not have the gametes come together, despite numerous attempts at creating offspring. Although there are diversity advantages that come through this method of reproduction, it is an uncertain method.
If population numbers are low for a species, it is possible for it to become extinct despite efforts at sexual reproduction because a zygote is unable to form.
3. Favorable genetics might not be passed to the offspring.
The offspring of two parents receives a combination of their genetics. Inheritance patterns are common with sexual reproduction. Patterns include autosomal dominant and recessive, x-linked dominant and recessive, and mitochondrial.
Autosomal dominant patterns occur in every generation and each affected offspring usually has an affected parent. Autosomal recessive patterns require both parents of an offspring to be affected. Huntington’s disease is an autosomal dominant disease and sickle cell anemia is an autosomal recessive disease.
In x-lined dominant diseases, female offspring are more likely to be affected than male offspring. The opposite is true for x-linked recessive diseases.
For mitochondrial inheritance, both males and females are effected, but mothers pass the traits onto their children.
4. Fewer offspring are typically produced.
Sexual reproduction can produce numerous offspring at one time. Humans may typically have one child through reproduction, but twins, triplets, and larger multiples are possible. Horses may typically have one foal, but cats and dogs may have more than a dozen in a litter. Compared to asexual reproduction, however, there are usually fewer offspring produced over time. With asexual reproduction, whenever an offspring is required, it can be produced. The same is not always true by using sexual reproduction.
5. It can be deadly.
Achieving an orgasm is the goal of sexual reproduction, but success sometimes comes with a price. Up to 5% of the human population has a brain aneurysm and the process of sexual reproduction can cause the aneurysm to rupture. There are 8 common triggers that cause a rupture and mating is one of them. That is because the process of sexual reproduction creates an increase in blood pressure.
About half of the people who experience a ruptured aneurysm will die from the bleeding that occurs within their brain. 1 in 4 people who survive will be left with a permanent disability.
Similar traits can be found in various animal species as well.
Sexual reproduction has many advantages and disadvantages to consider from a scientific standpoint. Genetic diversity can be created, but the process is uncertain and somewhat unpredictable. When practiced regularly, it can improve brain power, help to fight off disease, and make those practicing it feel good. There may be health risks involved, but for most species, the reward of sex outweighs its potential disadvantages.