Our site's main concern and reason why we started ysmad.com. To put species extinction into relation to other concerns (like global warming, pollution etc.): species extinction is considered the environmental issue exceeding sustainability by the highest percentage (at least it was 2010, when I found that in "Scientific American", article "Boundaries for a healthy planet").
"A conservative estimate of the current extinction rate indicates that about 27,000 species a year are being lost."
"Every day, an estimated 100 plant and animal species are lost to deforestation"
"Every year, 13 million hectares of tropical forest - an area the size of Illinois - disappear in smoke and as lumber. (...) Thousands of species disappear forever."
See sources of these claims and more like this on a separate page. Or visit well.com to find an article compilation "Mass extinction underway" : "Human beings are currently causing the greatest mass extinction of species since the extinction of the dinosaurs (...), as a result of habitat destruction, pollution, invasive species, and climate change."