Male Great Eggfly

It was end of Jack fruit (Artocarpus heterophyllus) season. Monsoon was about to start. Lot of ripe Jack fruit grown in our garden was getting wasted. So we thought of drying them in sunlight and create a sun-dried Jack fruit which can be preserved and eaten later during rainy season. First day of drying went on very well as on that day sunlight was bright and strong. Second day was cloudy. Jack fruit instead of getting sun dried, started getting soggy. It was attracting flies and butterflies. Smell of the ripe and rotting jack fruit was irresistible for few Male Great Eggflies (Hypolimnas bolina) who started to feast on these ripe Jack Fruit. I was able to photograph few of them as they were feasting on the sweet jack fruit and later resting on our garden plants.

Here I used Canon EOS 5D Mark III with Canon EF 70-200mm f/2.8L IS II USM. As I could not approach them very close (they would fly off) I could not use 100mm macro lens was not used. My trusty 300mm f/2.8+ 1.4x would have been ideal but I wanted to try the sharpest of my zoom 70-200mm f/2.8L IS II. Even though it is not a macro lens it provided me enough distance to capture them quite sharply. All were photographed at 200mm focal length. I used available sunlight to help me lighting these photos.

The Great Eggfly (Hypolimnas bolina), belongs to Genus Hypolimnas butterflies which are known as Eggflies. It also called Blue Moon Butterfly or Common Eggfly. The Great Eggfly is a black-bodied butterfly with a wingspan of about 7–8 cm. The species has a high degree of sexual dimorphism (male and female look totally different). The female mimics multiple poisonous butterflies. In the male the upper side of the wings are jet black, offset with three pairs of white spots – two on the fore-wing and one on the hind. These white spots are surrounded by purple blue iridescence. In addition, the upper side of the hind wing bears a series of small white dots. The upper side of the wings of the female is a brownish black and does not have any spots like those of the male. The edges bear white markings which are similar to those of the Common Indian Crow (Euploea core).

This is a fairly common butterfly found in lightly wooded country, deciduous forests, thick and moist scrub and the greener parts of human habitation. They are found in Madagascar in the west, through to South and Southeast Asia, South Pacific islands and occurs in parts of Australia, Japan and New Zealand. Great Eggflies are known for maternal care, with the females guarding leaves where eggs have been laid. Males are also very territorial and site fidelity increases with age. Territories that enhance the detection of females are preferred. The female hovers over a plant to check for ants which will eat her eggs. After selecting a plant which has no ants on it, she lays at least one but often two to five eggs on the undersides of the leaves. The eggs are a pale, glassy green with longitudinal ridges except on the top. You can check the Lifecycle of Great Eggfly on Dr.K.Saji’s Flickr page

Recently Great eggfly was in the news as it showed how scientists can literally watch evolution in action. The male-to-female ratio of Great eggfly has shifted rapidly over time and space, driven by a parasite that specifically killed males of the species, and rapid evolutionary change in the butterfly was witnessed as described in a report published online in Current Biology.

On the Samoan Islands of Upolu and Savai’i, a parasite (probably Wolbachia) had been killing the male members of Hypolimnas bolina. The problem was so severe that by the year 2001, males made up only 1% of the population. However, in 2007, it was reported that within a span of just 10 generations (less than a year), the males had evolved to develop immunity to the parasite, and the male population increased to nearly 40%. These findings give new insight into the reproductive ecology, more importantly, they show how scientists can literally watch evolution in action.

By the way if you are wondering the fate sun dried jack fruit, it did not dry but got rotten. Flies especially Blue Bottle Flies had laid eggs in them and we had to use it as a nice manure for our garden 😉