Ultraviolet rays penetrating through the protective ozone layer over Antarctica are damaging the DNA of higher animals. Scientists from the Northeastern University of Texas, US, found extensive DNA lesions in the eggs and larvae of ice fish - an Antarctic fish that lacks hacmoglobin - during the period when the ozone hole was the widest. In recent years, investigators have found that reproduction rates of algae-plant micro-organisms living in the underside of Antarctic sea ice have decreased due to the ozone hole. Algae come at the bottom of the food chain and are essential for the survival of marine animals.