John Barron Moore says that Nature is not a passive landscape that will let humans continue to overpopulate unchecked.
The one thing Nature hates is overpopulation of a monoculture. Mankind is now a global species. We are spread all over the Earth, turning the planet into an island in space. Almost every spot on the globe can be reached within 24 hours via aircraft from any other point. We are cutting down the rain forests for lumber for building our civilization and rain forests have the greatest biodiversity of any ecosystems on the planet. They also have some of the worst tropical diseases on record. CDC’s worst nightmare is an Ebola-like virus being spread by airline across the globe, but now I understand. If we destroy the rain forests, likely some virus or combination of viruses will emerge and will kill us. Just one good plague and the human race is in check again. If it’s a fast plague, something that kills in 72 hours or less and is highly contagious, then our public health systems would be unable to cope. So, the lack of Siglecs to moderate our immune systems is our Achille’s Heel or "Off Switch" — Nature’s last chance to bring everything back into balance again if we are too stupid to do it ourselves.