04, Jun 2019
Prelims level : Mains level :
Why in News?
- About a week ago, the New England Aquarium in the US announced that a “virgin”
anaconda had given birth during the winter.
- This is Immaculate Conception in Catholicism; in scientific terminology, it is
- This is only the second known case of parthenogenesis in green anacondas. It is not
unknown in snakes, but undocumented enough to make it to scientific journals.
- The term parthenogenesis is a amalgam of the Greek words parthenos meaning virgin and
genesis meaning origin.
- About 2,000 species are known to reproduce through parthenogenesis, which is one of the
known means of asexual reproduction.
- It is a reproductive strategy that involves development of a female (rarely a male) gamete
(sex cell) without fertililisation.
- It occurs commonly among lower plants and invertebrate animals (particularly rotifers,
aphids, ants, wasps and bees) and rarely among higher vertebrates”.
- A gamete is the egg in females and the sperm in males. In animals, parthenogenesis means
development of an embryo from an unfertilized egg cell.
- Many species that reproduce through parthenogenesis do not reproduce sexually. Others
switch between the two modes taking cues from the environment.
How are the babies?
- Babies born through parthenogenesis are clones of the mother, as has now been confirmed
by the aquarium through DNA tests.
- Parthenogenetic offspring tend to be clones of the parent because there has been no
exchange and rearrangement of genetic information with another individual as happens in
case of a sexual reproductive process.
- In some species, offspring born by parthenogenesis from a mother can also be male but it
lacks one X chromosome.