It couldn’t get more bizarre than this – insects that perform photosynthesis! And no, it’s not science fiction but one of the hard truths of nature. It has always been known that photosynthesis is the exclusive preserve of trees and plants and through this food producing process they sustain themselves. By absorbing carbon dioxide and letting off oxygen in the air, plant life ensures that the world remains an environmentally safe place, one reason why removal of trees in Melbourne or that matter anywhere else is strictly regulated. Now, turning all established theories on their heads, scientists have discovered that photosynthesis like process is also found in insects.
These insects are aphids, and their biological structure is often striking to say the least. Aphids have been known to be pregnant at birth and some of their male species often lack mouths resulting in their death soon after mating. But how photosynthesis? In studies conducted and research findings published, it is shown that aphids have the ability to capture sunlight and like plants, use the energy for metabolic purposes. This is what makes then unique in the insect world.
Certain pigments known as carotenoids exist in different creatures and these are put to a variety of purposes including manufacturing vitamins and ensuring a healthy immune system. But what sets them apart from aphids is that they absorb the pigments from their food. And this is where it differs for aphids. Entomologist Alain Robichon at the Sophia Agrobiotech Institute in Sophia Antipolis, France, and his colleagues have shown that aphids absorb energy from the sun and move it to their cellular machinery that is responsible for production of energy.
Scientists however are hedging their bets. Maria Capovilla, an entomologist at the Sophia Institute says that more work needs to be done on the subject before it can be conclusively proved that aphids truly photosynthesize but hastens to add that findings so far surely point in that direction. One of them is the physical structure of the creatures. The pigments are formed in a layer about 0 to 40 micrometers under the insect’s cuticle and this makes it ideal to capture sunlight.
Maria Capovilla also notes that the photosynthesis function of aphids could help them maintain energy levels and facilitate their movement from one plant to another. This is coupled with the fact that aphids consume and maintain more sugar levels than they actually need. It is also now known that the body colour of aphids depend on the carotenoids and that it changes according to the surroundings. It ranges from orange in optimal conditions to green in cold environments. In places where resources are limited, aphids are born white devoid of the pigment.
Research in this field is at an ongoing stage with entomologists coming up with newer and newer findings in this regard. The coming days are expected to open up fresh empirical data and findings on the subject of Photosynthesis in insects.