Imagine this: asexual reproduction. What if you could replicate on your own, without a partner? That would be fantastic, wouldn’t it? Life, as they say, finds a way; for example, parthenogenesis may be one of life’s wacky tricks.
Why waste more time when you have the ability to make “half-clones” of yourself if no suitable male partner is available? That’s the logic behind this phenomenon.
Parthenogenesis is a form of asexual reproduction that produces offspring in the absence of fertilization or union of gametes. It is also known as virgin birth, which is a colloquial term.
The offspring produced in this process is known as the “parthenogen,” which results in all male offspring being produced by animals with two comparable chromosomes for “maleness” (ZW sex determination) and all female offspring being produced by animals with two comparable chromosomes for “femaleness” (XY sex determination).
The ability to maintain their species even without their mate is one of the major benefits why organisms choose this form of reproduction. The eventual loss of genetic variety due to the limited (to no) gene shuffling is, however, a significant shortcoming of it.
You’re still curious about it, aren’t you? So, here are the top ten most amazing creatures with asexual reproduction (i.e., virgin births), as promised:
Asexual Reproduction In Organisms or Virgin Birth Creatures
1. Zebra Shark
The zebra shark Stegostoma fasciatum is the first species to be included on this asexual reproduction species list. A study of a female zebra shark giving birth following three years of separation from her mate shocked the scientific community in January 2017, and there have already been prior studies on virgin births in sharks.
- The first ever documented female zebra shark to alter its reproductive strategy from sexual to asexual was the zebra shark Leonie, which lives in an aquarium in Australia.
- In order to survive and perpetuate during long periods of isolation, sharks are known to practice parthenogenesis.
2. Water Flea
The water flea, or Daphnia sp., is named after it. A flea’s hopping motion is the only one that can be seen underwater. Interestingly, the population of water fleas is entirely female during the majority of the rainy phase of the vernal pond.
- Since these asexual creatures can reproduce via parthenogenesis, the explanation is self-evident. As a result, their daughters are practically identical to their mother.
- Female water fleas produce eggs during reproduction and carry them in a dorsal brood (egg) pouch until they are ready to be hatched.
3. Walnut Gulch Scorpion
The Walnut Gulch Scorpion, which is only found in southern Arizona and reproduces asexually, comes next on this list. The head and abdomen of this species are reddish to brown in color.
- According to a research published in the journal Euscorpius, all 187 scorpion specimens belonged to the Vaejovidae family are identified as biological females. This is the first documented instance of parthenogenesis in North America.
- Parthenogenesis in scorpions is also thought to be induced by a particular bacteria called Wolbachia, which causes feminizations of arthropods, according to scientists.
4. Parasitic Flatworms
One of the few flatworms that can reproduce parthenogenetically is the parasitic flatworm Schmidtea polychroa. These flatworms can produce polyploid and parthenogenetic eggs, as well as haploid sperms, and are hermaphroditic.
- Despite this, scientific studies have shown that these parasitic worms engage in occasional sexual behaviors. It appears that such behavior is practiced by around 12% of the population.
In vertebrates, parthenogenesis is extremely unusual and complex. These organisms aren’t clones, despite the fact that they’re produced via parthenogenesis and have only a mother. In most cases, the child receives both halves of its mother’s genes and the other half from its father. The maternal chromosomes, on the other hand, double during parthenogenesis in order to form what is thought to be a complement. The turkey Meleagris is perhaps the most well-known parthenogenetic vertebrate.
- According to studies, unfertilized turkey eggs may occur in up to 30% of all cases (and up to 40% in selected cases). The Z and W chromosomes (males have ZZ while females have ZW) are seen in turkeys, as they are in all other birds.
- The US government documented around 50 adult “fatherless” turkeys in 1975.
- As compared to their fertilized counterparts, eggs developed through parthenogenesis tend to take longer to incubate. Nonetheless, since little shell is required, their stay inside the uterus is brief.
6. Komodo Dragon
The sex chromosomes of Komodo dragons are Z and W, just like birds; however, because there is no WW genotype, the embryo will simply be aborted and die. The offspring are all males (ZZ) as a consequence of this.
- Seven Komodo dragons in European zoos were reported to have had virgin births in a research published in the journal Nature.
7. Whiptail Lizards
The whip-tail lizard, which is native to Mexico and the United States Southwest, is another species capable of virgin birth (or asexual reproduction). Lizards in this species are exclusively reproducing via parthenogenesis.
- Surprisingly, despite the lack of males in their population, this species of lizards continues to exhibit mating behaviors.
- Since it further stimulates their reproductive success, such behavior of mounting other females, which is thought to be hormoneally driven, is very advantageous.
8. Boa Constrictor
Several snake species have been reported to engage in parthenogenesis. This species of snake was first seen reproducing asexually in 2010.
- Despite being placed inside a cage with multiple males, this Boa constrictor had two virgin births.
- Surprisingly, until this one, no vertebrate with the WW genotype has ever been documented to create a live WW kid.
9. Cape Honeybees
Virgin birth is more prevalent in honeybees than in other insects, particularly Cape honeybees. Only the queen bee in a bee colony is usually fertile and capable of mating with male drones, although this may vary. Female working bees are the offspring of the queen and male drone.
- Interestingly, these male drones are produced by female working bees via parthenogenesis.
- Moreover, certain types of parasitic bacteria may cause lady worker bees to become parthenogenetic.
Bdelloids, also known as members of the class Bdelloidea, are rotifers that resemble leech creeping movements and are named after the Greek word “bdella,” which means “leech.” This creature has also made it into the list of immortal animals, according to the immortal creatures article.
- Because they are regarded as the “most ancient asexuals,” this class of rotifers is possibly one of the most significant organisms in evolutionary biology.
- This class includes all female animals that create their own (female) progeny from unfertilized eggs asexually.
Virgin births are the last resort for most of the aforementioned species to continue their species. The majority of scientists believe that early vertebrates devised this technique as a way to conserve energy and save time when finding a mate is more trouble than it’s worth.
Much about the origins of virgin births, as well as how many species are capable of reproducing in this manner, remains unknown even with current technology.
AFTER ALL, SCIENTISTS STILL HAVE A LOT MORE TO LEARN ABOUT THIS PHENOMENON; AND PROBABLY THE NEXT ULTIMATE QUESTION THAT COMES INTO THEIR MINDS IS: “COULD A HUMAN NATURALLY BE PRODUCED BY VIRGIN BIRTH TOO“?