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HAVE YOUR CAKE & EAT IT TOO
- BEEFSEA
(HORNBILL 1996(1) -A BOMBAY NATURAL HISTORY SOCIETY PUBLICATION)



       The debate between the two goes on which sex is more fortunate? Men curse their luck for having to shave every day, and envy women who have a clean chin and are spared this daily chore. And women blame the injustice of having to undergo the pains of childbirth - something which, they complain, men are spared. Only the wearer knows where the shoe pinches, so the best way to have an unbiased opinion would be to change sex and find out what the other one has to endure. Unfortunately this is not possible for us. There are other creatures, however, who have the advantages - or is it disadvantages? - of changing sex during their lifetime.

       Many sea fishes and other marine animals routinely change sex as they grow. As a lot of energy has to be spent by a female in producing eggs, many fishes start life as males, and turn into females as they grow. But the reverse also happens; for example, groupers (Epinephalus) change from females to males as they grow. Among marine animals other than fish, giant clams (Tridacna gigas) start life as males. At an age of about six years, they change sex and become females.

       Parrot fish seem to be a confused lot; some start life as females and later become males, while others start life as males, but with female body colouration. (The colour pattern in the two sexes is different.) The coloration in wrasses is still more puzzling. Some wrasses have two different types of male and a number of intermediate colour phases as they change their sex. The result is that there are so many forms with different colour patterns, and unless one traces their life history as they grow, the various colour forms can mistakenly be thought to be different species.

       The moon wrasse (Thalassoma lunare) of our seas has a complicated love pattern. They are born as females or as primary males, both being dark green and not aggressive to others of their kind. Some of the females change into secondary males. They change their body coloration to bright blue, with bright pectoral (shoulder) fins and grow long filaments on their tail borders. They also become aggressive. Each secondary male bullies the primary males and controls a harem of females. As high tide comes in, he swims above the reef, performing loops in the water, flaunting his pectoral fins and quivering his body. The females, no longer able to resist him, rush up and mate with him. He may thus mate with eight or more females in a day. On a large reef, a secondary male is not able to control all the primary males, so that these too join the proceedings while he is busy with the females.

       The change of sex in cleaner fish (Fissilabrus dimidiatus) is more complex and is dictated by social order in the population. Within a territory is an adult male, three to six mature females and several sexually immature fish. The male - let us call him king - dominates and bullies all the females, giving a characteristic aggressive display as he tours his kingdom and comes across a female. Females dare not face up to him but have a pecking order. Female No. 1 - let us call her the queen - bullies all females in the territory but does not use the "male' aggressive display. Female No. 2 is subdued by No. 1, but bullies No. 3 and down along the line.

       The fun starts when the king dies. If the queen is not strong, a male from outside the territory may invade it and then becomes the new king. If this does not happen, the queen, now free of the king's nagging, starts changing sex. For about half an hour after the king's death, the queen behaves normally - bullying all other females. Thereafter she starts giving the characteristic male aggressive display to all females. Within a few hours, her maleness increases, and she (now 'he') starts visiting females in his territory. Within two to four days, he starts courting females and mating with them.

       While "he" is beginning to change sex and become a male, a male from outside the kingdom may invade the territory. If the intruder is stronger, he will depose the new "king", who will now start changing sex, again becoming a female. But if it can face the intruder and drive him away, it will remain a male, becoming the new king.

       If we see the sex organs of a female, we shall find that enclosed within the ovary is the rudiment of a testis - spermatogenic crypts filled with spermatids (the forerunners of sperms). As long as the queen was dominated by the king, the latent maleness was suppressed, but the moment the restraint was lifted her maleness increased, and in a fortnight the former queen (now 'king") became a full-fledged potent male.

       Clown fish (Amphiprion) start life as males, and then become females as they grow. They swim in small groups of a dominant female and several males. As in the cleaner fish (but with reversed sex roles), she bullies all the others in her group, so that they remain immature or subadult males. If the dominant female dies, the largest male of the group starts bullying all the other fish in his group and, in a month, turns into a female thereafter dominating alL others.

       One of the most embarrassing incidents in my life was related to sex - not mine but of fishes. In the forties, the freshwater fishes catla, rohu and mrigal - collectively called Bengal carps as they occur in the Ganges river, were introduced into Powai, a lake in the city's suburbs. In those days, the technique of artificially breeding the Bengal carps by giving pituitary gland injections was unknown. Moreover, they normally breed only in running waters. But somehow they settled down in Powai lake and in the sixties, even bred there.

       The mass breeding of these fishes, locally called 'wulgun', is a sight not easily forgotten. Tens of thousands of the fish breed in unison and their frenzied frolicking froths the water surface as if the lake is boiling. After their energy is exhausted in mating, they come to the lake's periphery to rest in water hardly fifteen centimetres deep. And then the massacre starts. Hundreds of nearby, slum-dwellers, joined by hungry dogs descend on the lake with an assortment of sticks and baskets and collect the fish which meekly allow themselves to be picked up.

       To the State Fisheries Department, the 'wulgun' was an easy opportunity to collect the fish's eggs, to be reared at a fish farm at the nearby Aarey milk colony. Preparations were made on a war footing. The drivers of the departments vehicles were given addresses of the technical staff, while junior scientists took turns day and night to watch for signs of breeding and report to headquarters. The breeding of the Bengal carps takes place when there is incessant heavy rain for many hours, and is preceded by that of smaller fish like barbs, and this is an indication that 'wulgun' would soon follow.

       I was an Assistant Director in charge of a fleet of 45' and 36' trawlers, but as manpower was short, I was one of the team of scientists assigned to participate in the egg collection.

       As the eggs were in waist-deep water, one of my colleagues and I found it more convenient to work in swimsuits. Our shirts and trousers were neatly folded and placed in one of the vehicles. But, as the lake bed was strewn with the stalks of palmyra palm leaves, with their horrible thorny spikes, I kept my slippers on, as also my raincoat and waterproof hat,in case there was a shower.

       The fish eggs from the lake were transported to the fish farm, where I was busy placing them in nylon enclosures to hatch. As the tanks at the fish farm were full, later batches of eggs were sent to our fish nursery, at Bandra (a western suburb of Mumbai).

       The two of us suddenly realised that the flow of our vehicles to Aarey had stopped. And our clothes were in one of these! So I telephoned the Bandra nursery to ask the vehicle to come back to Aarey. I was told that the jeep had left Bandra for the Aquariwn. On telephoning the Aquariwn, I learnt that the jeep had reached the Aquarium, and that the driver had locked it in the garage and left for home after a tiring day, little realising that our clothes were in it. To make matters worse, our purses and identity cards were with our clothes, and we were stranded without any money.

       We borrowed some money from our fieldmen and hailed a taxi. The way around Powai in those days was risky at night, as it was deserted and vehicles were often robbed. Added to that was our state, clad only in bathing costume, hat & shoes. Taxi after Taxi refused to take us, so we finally decided to wear our raincoats, fully buttoned up, even though it was no longer raining, and persuaded a taxi driver to take us home. Our ordeal was finally finished.

       Or was it, really? In those days, there was an octroi and police check-post at Sion, and the police used to have an occasional 'naka-bundhi' when all cars were stopped and searched. To our bad luck, our taxi was asked to stop. When the policeman peered inside, he saw the two of us with fully buttoned raincoats. As the rain had stopped he was very suspicious and asked us to get out of the taxi and unbutton our raincoats. He was not amused at our state of semi-undress and marched us off to the nearby police station. The inspector there was more polite and patiently heard our tale of woe. We had asked him that he could telephone our director who would prove our bonafides. He burst out laughing and offered us a cup of tea and some hot snacks. We had been shivering at the prospect of having to pass the night in a lock-up. He was magnanimous and arranged a police wireless jeep to reach us home.

       Our day-long drama of sex, suspense and a brush with the law-and-order machinery had ended on a bright note, though you should have seen the look of horror and disbelief on my mother's face when I finally reached home, well past midnight, escorted by a policeman and dressed as I was!


 
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