DR MORLEY READ / SCIENCE PHOTO LIBRARY DR MORLEY READ / SCIENCE PHOTO LIBRARY
Frog eggs on bark. These are the eggs of the Hyla sarayacuensis tree frog. The aquatic origin of amphibians (such as frogs) is reflected in the external fertilisation required to reproduce. The female produces this gelatinous material (known as frog spawn) that comprises a cluster of eggs. The male will fertilise the eggs as they are produced. Most tree frogs then deposit this spawn in or over water, leaving the tadpoles (some seen inside the spawn) to develop and be released into the water when the sacs burst. Others may brood their eggs, guarding them and bringing the tadpoles to water when they are mature. Photographed in Ecuador.
Model release not required. Property release not required.