Difference Between Parthenogenesis and Hermaphroditism

The main difference between parthenogenesis and hermaphroditism is that the parthenogenesis is a method of reproduction by which insects develop from an unfertilized egg whereas the hermaphroditism is a reproduction method in which an individual organism bears both male and female gonads. Furthermore, parthenogenesis generally produces haploid offspring while hermaphroditism produces diploid offspring.

Parthenogenesis and hermaphroditism are two types of sexual reproduction methods involved in the production of gametes.

Key Areas Covered

1. What is Parthenogenesis
     – Definition, Facts, Examples
2. What is Hermaphroditism
     – Definition, Facts, Types
3. What are the Similarities Between Parthenogenesis and Hermaphroditism
     – Outline of Common Features
4. What is the Difference Between Parthenogenesis and Hermaphroditism
     – Comparison of Key Differences

Key Terms

Apomixis, Hermaphroditism, Mating Partner, Parthenogenesis, Ploidy, Sexual Reproduction, Sequential Hermaphrodites, Simultaneous Hermaphrodites

What is Parthenogenesis

Parthenogenesis is a reproductive mechanism in which an offspring develops from unfertilized eggs. It commonly occurs in invertebrates such as bees, wasps, ants, aphids, rotifers, etc. and lower plants. It is rare in higher animals. Parthenogenesis in plants is also called apomixis.

Figure 1: Parthenogenesis in Water Flea

The embryo produced in parthenogenesis is mostly haploid since it develops from an unfertilized egg. Sometimes, a diploid embryo is produced due to the pairing of two chromosome sets. On the other hand, the offspring can be obligate; that is, it is incapable of sexual reproduction. Or else, it can be facultative and switch between sexual reproduction and parthenogenesis.

What is Hermaphroditism

Hermaphroditism is the condition of having both male and female reproductive organs within the same individual. It is more common in plants. In higher plants, the flower is the reproductive structure. Some flowers are hermaphroditic, bearing both pistil (female reproductive structure) and the stamens (male reproductive structure). In addition, invertebrates such as snails and earthworms are also hermaphrodites.

Figure 2: Hermaphroditic Flower

There are two types of hermaphrodites: sequential hermaphrodites and simultaneous hermaphrodites.

• Sequential hermaphrodites –  Either male or female reproductive organ is active at a particular time. Hence, the parent organism becomes respectively either the father or mother of the offspring. That means this type of hermaphrodites requires a mating partner in order to undergo reproduction. Birds, fish, and many plants are considered as sequential hermaphrodites.
• Simultaneous hermaphrodites – They use both sex organs at the same time, producing both male and female gametes. But, they prevent self-fertilization and require a mating partner for reproduction. Earthworms are simultaneous hermaphrodites.

Similarities Between Parthenogenesis and Hermaphroditism

• Parthenogenesis and hermaphroditism are two methods of sexual reproduction.
• Both methods involve the production of gametes.
• They can develop diploid offspring.

Difference Between Parthenogenesis and Hermaphroditism

Definition

Parthenogenesis refers to the reproduction from an ovum without fertilization, especially as a normal process in some invertebrates and lower plants while hermaphroditism refers to the condition of having both male and female reproductive organs.

Fertilization

The parthenogenesis does not undergo fertilization while hermaphroditism undergoes self-fertilization.

Offspring

Haploid offspring are produced in parthenogenesis while Diploid offspring are produced in hermaphroditism.

Occur in

Parthenogenesis occurs in insects and lower plants while hermaphroditism occurs in snails, earthworms, and many plants.

Mating Partners

Mating partners are not necessary for parthenogenesis while mating partners are essential in hermaphroditism.

Conclusion

Parthenogenesis is a reproductive method in which the unfertilized egg develops into a daughter organism. On the other hand, hermaphroditism is another reproductive method in which each organism bears both male and female reproductive organs. The main difference between parthenogenesis and hermaphroditism is the mechanism of reproduction.

Reference:

1. “Parthenogenesis.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 10 June 2016, Available Here
2. “Hermaphroditic Plant Info: Why Are Some Plants Hermaphrodites.” Gardening Know How, Available Here
3. “Hermaphroditism.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 18 Dec. 2017, Available Here

Image Courtesy:

1. “DaphniaMagna LifeCycle DVizoso” By Author=Dita Vizoso – Own work (CC BY-SA 3.0) via Commons Wikimedia  
2. “Hylocereus undatus 1” By Brocken Inaglory (CC BY-SA 3.0) via Commons Wikimedia