London, Sep 5 (IANS): By 2100, the number of mammal species going extinct globally is likely to reach 558 if conservation efforts are not stepped up, researchers have predicted.

For all the mammal species that have gone extinct so far, humans are almost entirely to be blamed, said the study published in the journal Science Advances.

"On the basis of the IUCN (International Union for Conservation of Nature)-based scenario, we predict 558 mammal species' extinctions globally by the year 2100," the study authors wrote.

"We are losing biodiversity every year, and with every extinct species and population, we lose unique evolutionary history," they wrote.

The current diversity of mammals consists of approximately 5,700 extant species. At least 351 mammal species have gone extinct over the past 126,000 years.

Out of them, 80 are known from historical reports since the year 1500, while all others are only known from fossil or zooarcheological records.

For the study, Tobias Andermann from University of Gothenburg in Sweden and his colleagues applied mathematical procedures that apply probabilities to statistical problems to the fossil records to estimate how mammalian extinction rates have changed over the past 126,000 years, inferring specific times of rate increases.

Based on current trends, the researchers predicted for the near future a rate escalation of "unprecedented magnitude."

According to these models, the extinctions that have occurred in the past centuries only represent the "tip of the iceberg", compared to the looming extinctions of the next decades.

However, the study authors noted that despite the high level of current threat, there is still a window of opportunity to prevent many species' extinctions by improving conservation efforts.