Over the past 4 billion years, lifeforms have evolved into the spectacular array of species that now inhabit the planet. While many species radiated into extensive families of closely related species, others are so unique that they alone embody millions of years of evolutionary history — sole representatives of entire lineages of the tree of life. Weird and wonderful species, such as the finger-probing aye-aye (Daubentonia madagascariensis) of Madagascar; the bulbous-snouted gharial (Gavialis gangeticus) of South Asia; and the prehistoric-looking shoebill (Balaeniceps rex) of Africa, fall into this latter category. But an increasing body of evidence indicates these evolutionarily distinctive species are frequently also those most at risk of extinction. Now, a new study estimates that the loss of such unique and threatened species from the jawed vertebrates alone could eliminate between 86 billion and 160 billion years’ worth of evolutionary history over the next 50-500 years. It’s an almost inconceivable amount of history to lose, according to Rikki Gumbs, a research fellow at the Zoological Society of London and lead author of the study. “The universe itself is only around 14 billion years old,” Gumbs said. “But [species are] so varied that it all adds up once you start combining all the evolution that has happened concurrently during our planet’s history.” Gharials diverged from other crocodilians more than 40 million years ago. This one was photographed in Nepal, where numbers have been slowly recovering in recent years. Image courtesy of Rikki Gumbs/ZSL. To arrive at their assessment, Gumbs and…This article was originally published on Mongabay
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