Close_up of two glass frog larvae tadpoles developing in their eggs, seven days after being laid. The glass frog is so named due to its translucent skin, through which internal organs can be seen. The heart is seen beating beneath its skin, and blood cells are seen moving through the prominent vessels. Glass frogs lay their eggs on leaves overhanging water, so that when the tadpoles hatch they fall into it. They inhabit moist tropical forests in Central and northern South America. Filmed in the Ecuadorian Amazon.