The world is full of biological diversity. Here lives a variety of animals, plants ranging from very small to large. Each animal is adorned with its own characteristics and is different from other animals. Their size, shape, color, habit and habitat have made the world diverse. The number of animals discovered on the earth so far is more than 1.2 million.
Besides, new animals are also being discovered. Each animal has some definite characteristics. One species differs from another in terms of their characteristics. Many times males and females of same species differ in shape, color and characteristics. But an extremely rare and variegated animal has found in Bangladesh whose are called Gynandromorphism and possesses both male and female characteristics.
The term Gynandromorphism derived from Greek words. (Gr., Gyne, woman + aner, man + morphe and form). Gynandromorphs are genetically and phenotypically chimeric specimens bearing separate male and female somatic characteristics in the same individual.
Gynandromorphism is very rare phenomenon. But the phenomenon is observed in Crustacea, Scorpions, butterflies, ticks, spiders, silkworms, fruit flies. It has been also reported in Birds, Mammals and Amphibians. The term was first described by Morgan and Bridges in Drosophila. Gynandromorphs are also known as gynanders.
Depending upon the position of sex tissue, Gynandromorphism may be of three types- Bilateral Gynanders, Anterior Posterior Gynanders and Sex Piebalds. In Bilateral Gynanders, One half of the body of the organism shows male characteristics while other half shows male characteristics.
In Anterior- Posterior Gynanders, anterior region of the organism shows the characteristics of one sex while posterior half region shows the characteristics of the other sex. In the Sex Piebalds, the body of an organism consists of female tissue having spots of male tissue scattered irregularly.
Gynandromorphism is extremely rare phenomenon. Scientists also don’t have any accurate information in this regards .It is thought that the phenomenon occurs due to chromosomal aberration.
A Gynandromorph may occur when sperm cells fertilize both the egg and the polar body, as a result two zygotes produce and they may interact and swap cell combinations. According to some articles, Hybridization, bacterial and viral infections, temperature variation, and mutations also have been implicated in the development of Gynandromorpshs.
Neurothemis tullia, commonly known as Pied Paddy Skimmer, is a very familiar dragonfly species in China, India, Malaysia, Hong Kong, Thailand and Vietnam. The dragonfly is also frequently seen in Bangladesh. They are commonly found near Ponds, Crop fields and in shrubs.
During a regular field trip to Faridpur on 29 August 2016, A dragonfly named Neurothemis tullia was found for the first time which bears Gynandromorphism. Ashikur Rahman Shome, then a 2nd year student of Department of Zoology, University of Dhaka, first observed the Gynandromorphism on the dragonfly Neurothemis tullia in that trip and later researched about it. The field trip was supervised by respectable teachers, Md. Mokhlesur Rahman and Md. Mahabub Alam, of Department of Zoology, University of Dhaka.
The head and wings of the dragonfly found in Faridpur reveal Bilateral Gynandromorphism. The abdomen looks like a male but the last part of the abdomen bears the characteristics of female. Recently a research paper under the title “An unusual case of gynandromorphism in Neurothemis tullia (Odonata: Libellulidae)” was published from Germany in the journal “Notulae odonatologicae” (A semi-annual companion publication to Odonatologica, published for the International Odonatological Foundation, Societas Internationalis Odonatologica (S.I.O.)) by Ashikur Rahman Shome, Md. Mokhlesur Rahman and Md. Mahabub Alam.
However, This feature called Gynandromorphism has not been found in any species of animal from Bangladesh before. It is the first dragonfly bearing Gynandromorphism in the Indian Subcontinent and South Asia. Earlier in 2009, a similar species of dragonfly from Kerala, India was claimed to have Gynandromorphism. But later it was proved to be Anromorphic female. In biology, Andromorph is a female that resembles a male and totally different from Gynandromorphs.
Gynandromorphs are a variety of unusual sexual form and we still don’t know the reason behind Gynandromorphism accurately. It’s still a mystery and there are a lot of questions about it. So extensive research is needed on this issue. It can provide different solution in genetics.
Ashikur Rahman Shome is now continue his Master’s degree on Wildlife Biology in Dhaka University and doing research on this. He wants to do research broadly on dragonfly.
Author: Student, Wildlife Biology Department, University of Dhaka, Bangladesh.