Unusual Methods of Reproduction in Organisms

Quck answer

Organisms have developed various ways of reproducing, some of which are quite unusual. Here are 10 weird ways organisms reproduce:

1. Parthenogenesis – some female animals can reproduce without a male using a process called parthenogenesis.

2. Hermaphroditism – some animals are both male and female, allowing them to self-fertilize or mate with other hermaphrodites.

3. Cannibalistic reproduction – some species of insects and spiders engage in cannibalistic reproduction where the male is eaten by the female after mating.

4. Fragmentation – some animals, such as starfish, can reproduce by breaking off a piece of their body and regenerating into a new individual.

5. Cloning – certain species can reproduce by cloning themselves, such as the komodo dragon.

6. Sperm storage – female animals can store sperm for extended periods of time, allowing for fertilization at a later date.

7. Translocation – some insects reproduce by transferring sperm from their genitalia to their mouth and then transferring it to the female during mating.

8. Polyploidy – certain plants can reproduce by doubling their chromosomes, resulting in offspring with twice the number of chromosomes as the parent.

9. Budding – some animals, such as hydra, can reproduce by budding off a smaller version of themselves.

10. Self-fertilization – some hermaphroditic animals can self-fertilize, producing offspring with genetic material from both parents.

These are just a few examples of the weird and wonderful ways organisms have adapted to reproduce.

Animal Facts

Seahorses seem to have a loving look in their eyes, but regardless of how organisms reproduce, it can be weird, scary, and fascinating. A Wired magazine article written by Bill Joy in 2000 warned of a catastrophic future where self-replicating robots would render human life irrelevant. However, there are several examples of strange reproductive possibilities in the present. In ancient Greece, Zeus swallowed his pregnant lover whole to avoid having more powerful children than himself. Here are ten bizarre ways organisms reproduce.

10: Virgin Dragons

Komodo dragons are capable of self-seduction.

Parthenogenesis, or virgin birth, is a common phenomenon among various creatures in nature, including mole salamanders, hammerhead sharks, and komodo dragons. A germ cell divides into four reproductive cells, of which only one has half the chromosomes needed to create a new individual. In parthenogenesis, the female gamete or egg contains a complete set of chromosomes and can stimulate itself to grow. Some species of insects alternate between parthenogenesis and sexual reproduction depending on the environment. Although parthenogenesis has not been observed in mammals, it has been induced in rabbits using temperature control and chemicals.

9: Revamping Nemo’s Story

The disappearance of the lone female clownfish from their cozy sea-anemone abode leads to Nemo becoming Nema.
LeventKonuk/iStock/Thinkstock

Parthenogenesis and hermaphroditic reproduction are two distinct concepts. In parthenogenesis, the female gamete single-handedly carries out the process. Hermaphrodites, on the other hand, are unique in that they can produce both male and female gametes owing to the presence of male and female reproductive organs.

Hermaphroditism is common in some species such as fish, snails, and flowers. In some cases, an organism may begin as male and become female later while in others, they may start as female and turn male. There are also organisms that remain as both sexes throughout their lifespan.

The reproductive lives of clownfish, as shown in “Finding Nemo”, are quite dramatic. A sequel to the movie seems warranted as clownfish prefer to reside in sea anemones, where a male and a female are in charge of a group of smaller male clownfish who cannot reproduce.

However, if the female breeder dies, the dominant male changes its gender to become the female breeder while the largest of the smaller males quickly grows to take on the role of sexually mature male breeder [source: UCB]. Pixar, it’s time for “Becoming Nema” to hit the screens!

8: Stealing Clutches

Two frogs share a romantic moment surrounded by eggs.
wulna/iStock/Thinkstock

Clutch piracy is a breeding strategy that involves naked frogs living in the Pyrenees and not Barbados, sporting neither eye patches nor cutlasses nor swigging rum.

The cold nights in the Pyrenees force frogs, who usually mate in the shadows, to copulate during sunny afternoons. This peculiarity allows researchers to keep a close eye on the process, leading to the observation of a strange deviation from the typical external fertilization.

External fertilization is the preferred reproductive strategy of several amphibians and fish. The process involves the female laying a clutch of eggs in the water, and a male depositing sperm on them. To ensure that the process is completed on time, a female frog permits a male to climb on her back, give her a big bear hug, and fertilize her egg clutch immediately. However, the male’s sperm may only fertilize a portion of the eggs in the clutch.

High in the Pyrenean ponds, male frogs outnumber the females significantly. As a result, gangs of piratical males roam the area hunting for freshly laid egg clutches. As soon as they find them, they try to fertilize any unfertilized eggs left. Researchers have discovered clutches with up to four different fathers! [source: Sanders]

7: Tricking Pollinators with Floral Deception

Most flowers have a mutualistic relationship with pollinators, such as bees, butterflies, and hummingbirds. In exchange for carrying grains of pollen from one flower to another, these pollinators receive a sweet sip of nectar. However, certain species of orchids find this strategy boring and are concerned about inbreeding. Ophrys apifera, also known as the bee orchid, has developed a unique and bizarre method of self-replication. This Mediterranean species has evolved to look exactly like a female bee with its head buried in a blue-petalled flower, mimicking the scent and even the texture of a bee. The male bees, deceived by the flower’s appearance and scent, attempt to mate with the flower and dislodge pollen packs pre-loaded with a special adhesive that sticks to their backs. The bee’s frustration plays into the orchid’s reproductive strategy, as the distance traveled while the bee was cooling his temper prevents inbreeding. This deception is so perfect that even its imperfections turn out to be advantageous. Orchids are not the only ones that are seduced by this floral wizardry, as orchid plants can be found flowering on windowsills around the world.

6: Multi-gendered Reproduction

Tetrahymena, a single-celled microbe found in freshwater environments, mostly reproduces through parthenogenesis. However, when it needs to adapt to changing surroundings, it can activate a dormant sex drive to maintain genetic diversity. What makes Tetrahymena’s reproductive behavior even more peculiar is the fact that it has seven genders, referred to as Types I through VII. Type I cannot mate with another Type I, but it can choose from the remaining six genders to reproduce and maintain genetic variation.

The new baby Tetrahymena contain all the genetic information necessary to develop into any of the seven potential types. However, their DNA undergoes a random process that ultimately results in one gender. This process is quite complex for such a small microbe!

Male pregnancy is not a new concept in the seahorse world. During reproduction, the male and female seahorses engage in an intricate and beautiful courtship dance before the female transfers her eggs to the male’s pouch. The male fertilizes the eggs and carries them until they hatch. He then cares for the young seahorses until they’re ready to leave his pouch. Meanwhile, the female prepares for another round of reproduction. A male seahorse can give birth in the morning and become pregnant again in the evening.

The rhizocephalans barnacle is a parasite that injects its cells into a crab’s system. The cells grow a root system that spreads throughout the host’s body and eventually emerges in the spot where female crabs carry their eggs. The parasite then lays its own eggs in the sac. If the host happens to be male, it changes shape to resemble a female. The parasite directs its host to deeper waters where it can avoid predators and competition for food.

The story of Hymenoepimecis argyraphaga, a parasitic wasp found in Costa Rica, is disturbing. The female wasp paralyzes a spider, lays an egg on its belly and leaves. The spider recovers, but the egg hatches, and the wasp larva feeds off the spider. The larva then injects a psychoactive substance into the spider, causing it to spin an unusual web, after which the wasp kills the spider, eats it, and uses the web to create a cocoon. Two weeks later, a fully grown Hymenoepimecis argyraphaga emerges, ready to repeat the cycle.

The crown-of-thorns starfish, a venomous invertebrate, eats coral reefs, and due to human activities, such as overfishing, their population can explode, leading to the destruction of the reef and habitat loss for the creatures that live there. Efforts have been made to kill off the excess crown-of-thorns, but their remarkable ability to regenerate has made this difficult. Their cells are “indeterminate,” meaning they can form new body parts, and in some circumstances, they can grow a whole new body from a severed limb. If humans could master this regeneration ability, they could regrow lost limbs and generate new ones, but it would be strange if these limbs grew into a new person.

1: Gendering in Communities

In order to maintain genetic diversity, older ferns control the sex lives of younger ferns.
pum_eva/iStock/Thinkstock

Teenagers have the ability to reproduce, which often causes their parents to try and control their sex lives. However, compared to the Japanese climbing fern, teenagers have it easy. The fully grown ferns, or gametophytes, can be males, females, or hermaphrodites, but self-fertilization leads to inbreeding, which is to be avoided. To maintain healthy genetic diversity, older females in the community secrete gibberellin, a chemical that causes the surrounding young ferns to become males [source: Zastrow].

Recently, the term “community” has become popular as a positive and necessary aspect of modern life. However, the gendering of climbing ferns shows that there may be limits to community involvement.

More Information Available

Author’s Note: 10 Unusual Reproductive Strategies in Organisms

Parasitologists argue that their research subjects should be respected for their survival strategies. After researching some of these organisms, I have come to agree that there is a certain psychopathic brilliance on display. However, some strategies, such as the exploitation of spiders by Costa Rican wasps, can be difficult to stomach. Despite the cruelty of evolution, there are also examples of elegant and unique reproductive strategies, such as the bee orchid.

Sources

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Davis, Haley. “Crown of Thorn Sea Stars.” University of North Carolina at Chapel Hill. 2007. (Sept. 11, 2015) http://www.unc.edu/courses/2007fall/masc/490/001/Coral Reef Decline/Crown of Thorns.html
Encyclopedia Britannica. “Gamete” May 5, 2015. (Sept. 7, 2015) http://www.britannica.com/science/gamete
Gambino, Megan. “Top 10 Real-Life Body-Snatchers.” Smithsonian. Oct. 23, 2011. (Sept. 11, 2015) http://www.smithsonianmag.com/science-nature/top-10-real-life-body-snatchers-116692496/?no-ist
Joy, Bill. “Why the Future Doesn’t Need Us.” Wired. April 2000. (Sept. 7, 2015) http://archive.wired.com/wired/archive/8.04/joy.html
Moyer, Melinda Wenner. “Can a Virgin Give Birth?” Slate. Dec. 21, 2007. (Sept. 7, 2015) http://www.slate.com/articles/news_and_politics/explainer/2007/12/can_a_virgin_give_birth.html
Pollan, Michael. “The Weird Sex Life of Orchids.” The Guardian. Oct. 8, 2011. (Sept. 9, 2015) http://www.theguardian.com/science/2011/oct/09/orchid-sex-botany-ziegler-pollan
Quirk, Trevor. “How a Microbe Chooses Among Seven Sexes.” Nature. March 27, 2013. (Sept. 8, 2015) http://www.nature.com/news/how-a-microbe-chooses-among-seven-sexes-1.12684
Sanders, Robert. “Clutch Piracy Revealed as Novel Mating Strategy in European Common Frog.” UC Berkeley News. Sept. 15, 2004. (Sept. 8, 2015) http://www.berkeley.edu/news/media/releases/2004/09/15_piracy.shtml
Simon, Matt. “Absurd Creature of the Week: The Barnacle That Invades Crabs in a Not OK Way.” Wired. July 24, 2015. (Sept. 9, 2015) http://www.wired.com/2015/07/absurd-creature-of-the-week-rhizocephalan/
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University of California Museum of Paleontology. “The Haploid Life Cycle.” (Sept. 8, 2015) http://www.ucmp.berkeley.edu/glossary/gloss6/haploid.html
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FAQ

1. How do male seahorses give birth?

Unlike most other animals, it is the male seahorse that carries and gives birth to the babies. The female seahorse deposits her eggs into a special pouch on the male seahorse’s abdomen, where they are fertilized and grow. The male seahorse then carries the developing embryos for up to several weeks, until they are fully formed and ready to be born. When it’s time for birth, the male seahorse undergoes muscular contractions to expel the babies from his pouch.

2. What is parthenogenesis?

Parthenogenesis is a form of asexual reproduction where females can produce offspring without the need for fertilization by a male. This can occur naturally in some species of insects, fish, reptiles, and amphibians, or it can be induced artificially in some laboratory settings. In parthenogenesis, the offspring are genetic clones of the mother, meaning they have identical DNA.

3. How do anglerfish mate?

Anglerfish have one of the most bizarre mating strategies in the animal kingdom. Male anglerfish are much smaller than females and lack their own digestive system. When a male finds a female, he bites onto her skin and releases an enzyme that fuses their skin and circulatory systems together. The male then slowly degenerates, providing sperm to the female as needed. In some cases, a female anglerfish may have multiple males attached to her at once.

4. What is hermaphroditism?

Hermaphroditism is a reproductive strategy where an organism has both male and female reproductive organs. This allows them to produce both eggs and sperm, and in some cases, fertilize themselves. Hermaphroditism is common in many invertebrates, such as snails and earthworms, as well as some fish, amphibians, and reptiles.

5. How do spiny orb weaver spiders mate?

Male spiny orb weaver spiders have a unique way of approaching females without getting eaten. They create a fake spider made out of their own silk and attach it to the female’s web. When the female approaches the fake spider, the male jumps out and mates with her. This allows the male to avoid being mistaken for prey and increases his chances of successful mating.

6. What is siblicide?

Siblicide is a phenomenon where offspring of a single clutch or litter compete with each other for resources, often resulting in the death of one or more siblings. This can be seen in many bird species, where the older and larger chick will often kill the younger and weaker siblings. In some species of sharks, the largest embryo will eat the smaller ones in the womb. Siblicide is a harsh but effective way for some organisms to ensure their own survival and increase their chances of passing on their genes.