Which organisms reproduce asexually

Studies found no evidence of a paternal genetic contribution. In , a zebra shark named Leonie in Australia gave birth to three baby sharks after being separated from her mate for five years. Genetic testing of tissue samples from the mother shark, the suspected father shark, and the offspring showed that the babies only carried DNA from their mother. Typically, Komodo dragon males engage in aggressive combat with each other during mating season. A Komodo dragon who had never had contact with a male in her life laid 11 eggs that tested for her DNA only.

Sea stars have the ability to reproduce both sexually and asexually, but with an interesting twist. Asexual reproduction in some starfish is achieved through fission, meaning the animal actually splits in two and produces two complete organisms. In some cases, starfish will voluntarily break off one of their arms and then regenerate the missing piece while the broken part grows into a whole other starfish.

Of the approximate 1, extant species of starfish, just 24 species are known to reproduce asexually through fission.

Some lizards, like the New Mexico whiptail, are unique in that they can reproduce asexually but still maintain DNA changes from generation to generation. A foot, year-old python named Thelma who lived full time with another female snake appropriately named Louise produced a clutch of 61 eggs despite having had no exposure to a male in two years.

The eggs contained a mixture of healthy and unhealthy embryos, eventually resulting in the birth of six healthy female babies. The marbled crayfish made headlines in when a German aquarium owner found a previously undiscovered species of crayfish that appeared to have cloned itself. The offspring were all females, suggesting that this new crayfish could be the only decapod crustacean which includes crabs, lobsters, and shrimp with the ability to reproduce asexually.

Since then, the unique species of marbled crayfish has formed wild populations throughout freshwater habitats in Europe and Africa, wreaking havoc as an invasive species. They were able to confirm that all of the crayfish were indeed clones descended from a single organism through the parthenogenesis form of asexual reproduction. The species had very little genetic diversity and was evolutionarily young, a rarity among asexual reproducing animals, and the timing was congruent with the original discovery in Germany.

They also estimated that the wild range of the invasive marbled crayfish increased fold between and A species of freshwater fish native to Mexico and Texas, Amazon molly fish are all female. In the case of this particular fish, however, asexual reproduction has worked out greatly in their favor. A study compared the genome of the Amazon molly to that of two similar species only to find that the mollies were not only surviving, but thriving.

They concluded that the molly genome had high levels of diversity and showed no widespread signs of genomic decay, despite being entirely female.

Wasps reproduce both sexually and asexually. In those that reproduce sexually, females are born from a fertilized egg while males come from unfertilized eggs. There are some populations of wasp that produce only females from unfertilized eggs, essentially laying eggs fertilized by their own personal DNA. Scientists have found that whether or not a wasp reproduces sexually or asexually is determined by a single gene.

Using crossing experiments in aphid wasps, researchers at the University of Zurich were able to demonstrate that the trait is inherited recessively, and that exactly Some ants have the ability to reproduce both sexually and asexually. In the case of common black carpenter ants, fertilized eggs will become female workers, while unfertilized eggs become males. Animals may reproduce asexually through fission, budding, fragmentation, or parthenogenesis.

Fission, also called binary fission, occurs in prokaryotic microorganisms and in some invertebrate, multi-celled organisms. After a period of growth, an organism splits into two separate organisms. Some unicellular eukaryotic organisms undergo binary fission by mitosis.

In other organisms, part of the individual separates, forming a second individual. This process occurs, for example, in many asteroid echinoderms through splitting of the central disk. Some sea anemones and some coral polyps also reproduce through fission. Fission : Coral polyps reproduce asexually by fission, where an organism splits into two separate organisms.

Budding is a form of asexual reproduction that results from the outgrowth of a part of a cell or body region leading to a separation from the original organism into two individuals. Budding occurs commonly in some invertebrate animals such as corals and hydras. In hydras, a bud forms that develops into an adult, which breaks away from the main body; whereas in coral budding, the bud does not detach and multiplies as part of a new colony.

Budding : Hydra reproduce asexually through budding, where a bud forms that develops into an adult and breaks away from the main body. Fragmentation is the breaking of the body into two parts with subsequent regeneration.

If the animal is capable of fragmentation, and the part is big enough, a separate individual will regrow. Many sea stars reproduce asexually by fragmentation. For example, if the arm of an individual sea star is broken off it will regenerate a new sea star. Fishery workers have been known to try to kill the sea stars that eat their clam or oyster beds by cutting them in half and throwing them back into the ocean.

Unfortunately for the workers, the two parts can each regenerate a new half, resulting in twice as many sea stars to prey upon the oysters and clams.

Fragmentation also occurs in annelid worms, turbellarians, and poriferans. Fragmentation : Sea stars can reproduce through fragmentation. The large arm, a fragment from another sea star, is developing into a new individual. Note that in fragmentation, there is generally a noticeable difference in the size of the individuals, whereas in fission, two individuals of approximately the same size are formed.

Parthenogenesis is a form of asexual reproduction where an egg develops into a complete individual without being fertilized. The resulting offspring can be either haploid or diploid, depending on the process and the species.

Parthenogenesis occurs in invertebrates such as water fleas, rotifers, aphids, stick insects, some ants, wasps, and bees. Bees use parthenogenesis to produce haploid males drones and diploid females workers. If an egg is fertilized, a queen is produced. The queen bee controls the reproduction of the hive bees to regulate the type of bee produced.

Some vertebrate animals, such as certain reptiles, amphibians, and fish, also reproduce through parthenogenesis. Although more common in plants, parthenogenesis has been observed in animal species that were segregated by sex in terrestrial or marine zoos. Two Komodo dragons, a bonnethead shark, and a blacktip shark have produced parthenogenic young when the females have been isolated from males.

Sexual reproduction is the combination of usually haploid, or having a single set of unpaired chromosomes reproductive cells from two individuals to form a third usually diploid, or having a pair of each type of chromosome unique offspring. Sexual reproduction produces offspring with novel combinations of genes. This can be an adaptive advantage in unstable or unpredictable environments. As humans, we are used to thinking of animals as having two separate sexes, male and female, determined at conception.

Asexual reproduction in plants can take a number of forms. Many plants develop underground food storage organs that later develop into the following year's plants. Potatos and daffodils are both examples of plants which do this. A daffodil bulb at the beginning and end of the growing season, with a lateral bud where the new plant will grow.

Some plants such as the spider plant, Chlorophytum, produce side branches with plantlets on them. Other plants like strawberries, produce runners with plantlets on them.