Penguins, a species of bird in the Spheniscidae family, are evolving too slowly and could soon suffer the disastrous consequences of climate change, a new study suggests.
The penguin is arguably one of the most fascinating seabird species in the world. Mainly evolving in the waters of Antarctica, Australia or New Zealand, this little cousin of the penguin seems to be adapting to its environment and to the disastrous consequences of climate change. But, this may soon no longer be the case.
A new study, shared by the journal NatureCommunications and relayed by ScienceAlert on July 22, 2022, affirms that the evolution of these seabirds would currently be much too “slow”, and that this evolution could harm the species – it will soon no longer be able to adapt to current climate change. , considered too fast for its ability to evolve.
The “slow” evolution of penguins would make them vulnerable to climate change
This review study NatureCommunications reveals to us the beginnings of the history of the first penguins. These small seabirds, close cousins of the penguin, would have adapted astonishingly and quickly to the climate and temperatures in the southern hemisphere (where temperatures are very high during the austral summer), after the extinction of their ancestor, they several hundred thousand years ago: the Palaeeudyptes klekowskii.
The study cites that after the disappearance of the dinosaurs, some birds, especially penguins, had more room to spread and reproduce. Small seabirds have settled in places with different climates, all over the world. These also eventually evolved into large marine predators.” Over 60 million years, these iconic birds have evolved into highly specialized marine predators, and are now well adapted to some of Earth’s most extreme environments. », Specifies the authors of the study.
However, scientists’ research reveals that penguins now have an extremely slow rate of evolution (possibly the slowest of all bird species in the world). The study claims that the mass extinction is the main cause of the slowdown in their rates of genetic mutations, and this, since their transition to marine life ” the current rate of global warming, combined with the limited number of refuges in the Southern Ocean, will likely far exceed the penguins’ ability to adapt. »
The researchers compared 17 different species of birds in total. They noticed that waterfowl generally had slower rates of evolution than landbirds. The researchers believe that an aquatic lifestyle could be the main cause of a low rate of evolution. They also believe that rates of evolution in birds are lower in cooler climates, such as Antarctica: Bird evolution rates are lower in cooler climates. »
The consequences of physical isolation for penguins
Penguins have had to adapt to repeated climatic changes and diverse marine environments over several thousand years — scientists have found that several species of penguins experienced a period of physical isolation during the last Ice Age.
Penguins have dispersed several times in South America and Antarctica. This isolation prevented them from being in contact with other penguins and forced them to live in more fragmented habitat areas, and in which they could find food or shelter less and less. As a result, the DNA of each penguin species has become different and more specific.