Last year, Australia officially recognized the first extinction of a species due to climate change. We are talking about a reef mosaic-tailed rat, which global warming has deprived of its usual habitat. Platypuses, turtles, Pacific killer whales and nearly a million other plant and animal species are on their way, according to members of the Intergovernmental Panel on Biodiversity and Ecosystem Services (IPBES). According to the forecasts of Danish and Swedish researchers, by the end of the century almost all endangered animals will disappear, which means that the planet has entered an era of a new mass extinction.
Even insects disappear
According to IPBES experts, a tenth of all existing plant and animal species will disappear in the coming decades. More than 40 percent of amphibians, 33 percent of reef corals and more than a third of marine mammals are at risk. Also, almost a quarter of all terrestrial species are at risk.
In addition, scientists have recorded a rapid decline in the number of insects. According to the latest data, their total biomass is declining by two and a half percent per year. Among the most affected regions of the planet is the tropics of Puerto Rico, where insects have decreased by 78-98 percent over the past 36 years. The researchers note that the decline in their numbers has already led to the extinction of birds, frogs and lizards that fed on them.
“Given the rate of extinction of species and the rate of decline in the number of other representatives of flora and fauna, we are living in an era of mass extinction of species. But we are, apparently, at the initial stages of this era. Its most destructive and, in many cases, irreversible consequences are yet to come,”said Director of the Center for Wildlife Conservation Alexei Zimenko in a conversation with RIA Novosti.
The charts show the proportions of endangered species of all plants and animals known today. Amphibians are in the greatest danger now - according to scientists, more than 40 percent of the species of these animals may disappear in the coming decades.
Man comes as a killer
Most studies blame humans for the current catastrophic situation. According to IPBES, humans have changed the face of 75 percent of the land and affected 40 percent of the world's oceans in one way or another. Today, more than a third of the surface is used for agricultural purposes, mainly for growing plants and grazing livestock. About one third of commercial fish are caught in excess. In total, people extract up to 60 billion tons of renewable and non-renewable resources annually. This is twice as much as half a century ago.
According to the work of American and Chinese scientists, the populations of many modern endangered vertebrates began to decline sharply at the end of the 19th century, when industrialization began in most countries of the world. Experts have analyzed over ten thousand studies on the genetic diversity of 2,764 species. The conclusion is disappointing: the number of endangered animals decreases by 25 percent every ten years. At the same time, today the average size of populations of endangered species is only five percent of their number at the end of the 19th century.
“I don’t undertake to quantify the rate of extinction, there is data on this score from authoritative research teams, including international ones. But it is definitely very high and more than dangerous. Such values are not characteristic of stable periods in the development of the biosphere and rather correspond to catastrophic epochs in the history of the Earth. In the future, animals and plants living in a narrow range of habitats (say, in one tract), in landscapes most disturbed by humans (steppes) or subject to climatic changes (dry subtropics, the Arctic) will suffer the most (and have already suffered). Also at risk are highly specialized food species and higher order predators. The latter are under threat due to the accumulation of a large amount of pollutants in their food facilities,”said Alexey Zimenko.
According to him, the current situation can play into the hands of animals that are picky about food and easily adapt to life in any conditions.
“It is unlikely that the well-known gray rat, hooded crow and similar species with extremely high adaptability to external conditions will seriously suffer. But there are very, very few such species. They are not able to ensure the normal functioning of natural ecosystems,”the scientist emphasized.
Kingdom of rodents
Danish and Swedish biologists estimate that 99.9 percent of endangered animal species and 67 percent of vulnerable species will disappear during this century. First of all, representatives of the megafauna - elephants and rhinos will die, and populations of small animals like rats will increase. At the same time, it will take our planet from three to five million years to restore biodiversity to at least the current level. It will take another two million years to return to pre-Homo sapiens levels.
The authors of the work suggest that in the future the Earth may become a kingdom of rodents: there are many of them and they easily adapt to new habitat conditions. Therefore, they will be able to survive the next mass extinction. But the loss of representatives of the elephant family - the Indian and African elephants - will actually chop off another branch on the evolutionary tree. Scientists propose, first of all, to save just such animals. Priority species include black rhino, red panda and indri.
“The species that are under threat today will become extinct if the policy and practice of land use do not change significantly, if they do not become less destructive to natural ecosystems. If everything is left as it is, we will face a loss or a sharp decline in ecosystem functions, without which human life is impossible. At best, a mass extinction will lead to a complete renewal of the biosphere: the formation of new natural systems, landscapes, and other flora and fauna. This will take many millions of years. In the end, nature will probably survive. But it will be a completely different nature. I'm not sure that there will be a place for a person in the new biosphere,”concluded Aleksey Zimenko.