Asexual Animals

Animals that Only Reproduce Asexually

1. Amazon Molly Fish

Amazon mollies reproduce entirely via a form of parthenogenesis called gynogenesis. A freshwater fish living in parts of North America, the Amazon molly possesses diploid eggs, which are fertilized by males of closely related species like the Atlantic molly.

However, no genetic material is passed on from the males, leading to almost identical clones of the mother being born. Despite this, there is enough genetic diversity in the genome of this fish to prevent extinction.

2. Bdelloids

A family of rotifers consisting exclusively of females, species belonging to the Bdelloidea family undergo parthenogenesis to propagate their life cycles.

3. Marbled Crayfish

The only decapod crustacean known to reproduce asexually, the marbled crayfish consists of an entirely female population. It is a triploid organism possessing 276 chromosomes that give birth to offspring utterly identical to the parent.

4. New Mexico Whiptail

The New Mexico whiptail is a parthenogenic lizard consisting of an all-female population. They lay about four unfertilized eggs that hatch about eight weeks later. Interestingly, these whiptails engage in mating behavior with other lizards, with only participating females going on to lay eggs.

5. Walnut Gulch Scorpion

These rare scorpions are generally reliant on Wolbachia to reproduce. Wolbachia are bacteria known for aiding in the reproduction of arthropods by altering their biological sex or inducing parthenogenesis in them.

6. Water Fleas

While sexual reproduction is occasionally observed, these tiny crustaceans generally reproduce by parthenogenesis, with offspring ending up identical clones of their parents for generations.

Animals that can Reproduce Asexually and Sexually

1. Ants

Queen ants of several species will produce worker ants via parthenogenesis.

2. Aphids

Aphids alternate between asexual and sexual reproduction, with young being born from both parthenogenesis and fertilized eggs.

3. Bees

Similar to ants, the queens give birth to males via asexual reproduction and females through sexual reproduction.

4. Boa Constrictor

In 2010, a female boa constrictor gave live birth to 22 offspring, each half clones of their mother. She did not interact with any males during this time.

5. Hydra

One of the longest living animals, Hydra refers to a collective genus of freshwater microorganisms that constantly regenerates itself via parthenogenesis. In harsh conditions, they may exhibit a form of sexual reproduction, but this only occurs in a few species.

6. Komodo Dragon

While Komodo dragons engage in sexual reproduction, in the absence of males, females lay unfertilized eggs that hatch to become male dragons.

7. Python

A 62-year-old ball python in the St Louis Zoo laid eggs despite not being close to any males in over a decade. She was also the oldest snake in recorded history ever to give birth.

8. Sponges

While capable of sexual reproduction, sponges are known for asexual reproduction via several means. This includes budding, fragmentation, and gemmule production.

9. Starfish

Starfish, or sea stars, have displayed the capability for both sexual and asexual reproduction. While sexual reproduction involves the male and female releasing sperm and eggs, respectively, into the environment, asexual reproduction takes place through binary fission and regeneration.

10. Stick Insects

If left alone, female stick insects give birth by laying unfertilized eggs, which become females if not fertilized by males.

11. Wasps

Wasps give birth to only female offspring when they reproduce asexually.

12. Zebra Shark

A zebra shark named Leonie gave birth to a litter of pups in an Australian museum asexually. Interestingly, she had given birth with the help of a mate before this but had been separated from him for three years.

One of her daughters, Lolly, would also go on to give live birth asexually later on.