Biologists have built a model of phylogenetic relationships between animal species and estimated the extent of decline in global biodiversity associated with human activities. For example, they took representatives of the class of reptiles. The study is published in the journal Nature Communications.
In geological history there were five mass extinctions, when the face of the Earth has gone up to 75 percent of all species. In our days people ruthlessly displaces animals from their usual habitats, creating unbearable conditions for them existence. The process of economic development of the world threatens to become the sixth mass extinction.
Scientists from the UK, USA and Israel, for example, reptiles appreciated the scale of the disaster. It is known that reptiles are one of the most vulnerable classes of terrestrial vertebrates, since they are closely tied to habitat.
"Is one of the most incredible and underrated animals on the planet — presented in a press release quotes first author of the article phylogenetics Ricky Gambs (Rikki Gumbs) from Imperial College London. — From legless lizards and the tiny blind snake and ending with the pink, worm-like amphibians, we know very little about these amazing creatures, many of which can discreetly slide into extinction".
The authors constructed a phylogenetic model for the 25 million living species of reptiles, which traced their evolutionary relationship with extinct predecessors, assessing thus the duration of the evolutionary history for each species.
"We are destroying not only individual species, the scientist said. We cut down whole branches of the evolutionary tree of life".
The evaluation conducted by the authors for all members of the vertebrates, today under threat of extinction are groups representing a total of more than 50 billion years of evolutionary development. For example, could soon be lost to a whole bunch of closely related species of pangolins and tapirs. And there are all unique types, such as Malagasy reconozca — the last on Earth, representatives of a very long evolutionary branches.
Animals from different branches of evolution are usually different special features and unique ecological functions. The disappearance of whole branches, they note, is much more dangerous for the preservation of natural balance, than the extinction of individual species.
"Our analysis shows the incomprehensible scale of the losses — continues Gambs. — Some reptiles can lose at least 13 billion years of unique evolutionary history — about the amount of time passed since the beginning of the existence of the whole universe".
Reptiles are faced with a greater loss of phylogenetic diversity than amphibians, birds or mammals.
"Our analysis shows that the concentration of species diversity of reptiles coincides in places with high human activity," write the authors.
It is primarily on arid and semi-arid regions of the Middle East and some parts of Africa, as well as India and Caribbean Islands. In these regions with high anthropogenic impacts are practically absent environmental control.
