China News Service, Chengdu, October 27 (Wang Liwen) Researchers from the Chengdu Institute of Biology, Chinese Academy of Sciences, systematically analyzed the evolutionary history of unique terrestrial animals on the Tibetan Plateau and surrounding areas, revealing a new mechanism for the formation of animal diversity in the Earth's "Third Pole". The relevant results were published in the international academic journal Proceedings of the National Academy of Sciences on October 27.
The Qinghai-Tibet Plateau covers an area of approximately 3.07 million square kilometers and is one of the global biodiversity hotspots. For a long time, the connection between plateau uplift, climate change and biological evolution has attracted much attention. However, previous relevant studies have mostly focused on flora or single animal groups, and there is a lack of systematic understanding of the overall formation process of plateau terrestrial fauna.
The research team focused on 527 species of endemic terrestrial animals on the Qinghai-Tibet Plateau, covering multiple groups such as invertebrates, amphibians, reptiles, birds and mammals, and combined the phylogenetic information of more than 20,000 species of animals to reconstruct the historical process of the formation and spread of endemic animals.
Research statistics show that a total of 367 in-situ differentiation events, 103 immigration events, and 56 emigration events occurred during the formation of endemic animals on the Qinghai-Tibet Plateau. Among them, the Hengduan Mountains contributed 201 in situ speciation events, significantly higher than those in the Himalayas and the interior of the plateau. It is an important "engine" for the formation of endemic animals.
"In the past, people paid more attention to how the uplift of the Tibetan Plateau promoted the evolution of life, but new research shows that different regions play different roles in the formation of life." The researchers said that the complex terrain and diverse climate environment of the Hengduan Mountains provide important conditions for species isolation, adaptation and differentiation, while the plateau table is more characterized by the migration and accumulation of species.
The study also found that the formation of animal diversity on the Tibetan Plateau was not simply driven by plateau uplift. The Eocene-Oligocene climate transition about 34 million years ago may have initiated a sustained process of animal diversification and exchange, and its impact preceded some late Neogene tectonic uplift events. The uplift history and monsoon environment differences in different regions jointly shape the different evolutionary trajectories of each region.
In addition, research has revealed an important connection between the evolution of plants and animals. The establishment of plant groups may provide an ecological basis for the subsequent immigration and diversification of animals, showing an evolutionary model of "plants first, animals later".
The Tibetan Plateau is an important natural laboratory for studying the adaptation of life to extreme environments. This study reveals the spatiotemporal process of the formation of plateau animal diversity, provides new scientific basis for understanding how changes in the earth's environment affect the evolution of life, and also provides important theoretical support for the conservation of biodiversity on the Qinghai-Tibet Plateau.
