Highly Versatile Treefrog Facing Effects of Climate Change

Climate change has qualified to be the biggest threat of this century. And, the damage caused by the human activity is seen now in frogs.

The dendropsophus ebraccatus, commonly known as the pantless treefrog or hourglass treefrog is known for its reproduction pattern which is different from most other frogs. Belonging to the Hylidae family this frog can lay its eggs on land or in water depending on its surrounding environment. It is the only vertebrate animal known to be capable of laying eggs both in water and on land.

This behavior protects the eggs from the aquatic predator such as fish and tadpoles, but simultaneously increases their risk of drying out.

According to Justin Touchon, post-doctoral fellow at the Smithsonian Tropical Research Institute discovered that climate change in Panama may be altering frogs' course of evolution.

For the study the researchers discovered that the long term rainfall data collected by the Panama Canal Authority showed changing rainfall pattern just as climate change models predict.

"Over the past four decades, rainfall has become more sporadic during the wet season," said Touchon. "The number of rainy days decreased, and the number of gaps between storms increased."

Due to this alteration in weather patterns the advantage of laying eggs out of water has drastically reduced. This is not just with pantless frog but with many other species.

The embryos of the pantless frog die within a day when there is no rain. Heavy rains increase breeding so as storms become irregular, the chance of rain within a day of being laid decrease and so does egg survival.

However, all is not lost. "Pantless treefrogs can switch between laying eggs in water or on leaves, so they may sustain the changes we are seeing in rainfall better than other species that have lost the ability to lay eggs in water," said Touchon. "Being flexible in where they put their eggs gives them more options and allows them to make decisions in a given habitat that will increase the survival of their offspring."