Frogs in Siberia have evolutionarily adapted to climate change

This allowed amphibians to withstand the extremely low temperatures during the winter season caused by climate change.

Photo by: Wikimedia Commons

Scientists from the Novosibirsk Institute of Cytology and Genetics (ICG), together with their colleagues from the Institute of Biological Problems (IBPS) in Magadan, have discovered how Siberian frogs manage to survive during the harshest frosts. The amphibians were found to produce ethyl alcohol and glycerine, which help them survive the harsh climate. The finding was revealed in a scientific paper published in the Siberian Branch of the Russian Academy of Sciences, Science in Siberia.

The researchers found that the Siberian frog Rana amurensis can live for up to six months in water with almost no oxygen. And the sharp-mouthed frog Rana arvalis and the salamander Salamandrella keyserlingii, known as the Siberian eelgrass, tolerate freezing, which stops their blood circulation, in the topsoil.

The sharp-legged frog can survive as cold as −16°C, while the Siberian salamander can withstand freezing temperatures as low as −55°C.

Scientists stressed that the sharp-mouthed frog and angelfish have adapted well to life in the Siberian winter and come back to life in spring without any harm to their bodies. Only the Siberian frog dies when frozen, so it overwinters in non-freezing water bodies.

Biologists in the laboratory studied the organisms of all three amphibians and found that they accumulate glycogen in the liver in autumn. This is a polysaccharide that breaks down into glucose and glycerol in winter. The elements supply energy to amphibian cells before freezing and then protect them from freezing when tissues switch to oxygen-free metabolism.

They also found ethanol in frogs and salamanders, which has never before been found in such quantities in terrestrial vertebrates. The researchers did not specify exactly how ethanol helps amphibians survive the harsh cold.

Scientists have not yet figured out why the Siberian frog supplies itself with glycerine. This substance helps protect tissues from freezing, but this amphibian species cannot tolerate freezing.

Recently, scientists have increasingly found evidence of species adaptation to a changing climate.

For example, US researchers from Florida Atlantic University have discovered that the Pacific cat sharks have learned to get out of the water and walk on land using their fins, travelling up to 30 metres “on foot” and doing without dissolved oxygen in the water for up to two hours.

Biologists say the fish have adapted to walking on land because of the sudden tides and rising sea temperatures. Thus, sharks are able to move from body of water to body of water in search of food, which helps them survive better than other species.

Cover photo: Wikimedia Commons