Group Of Scientists Prioritize Which Endangered Species To Save Using Evolutionary Relatedness

Feb 5, 2018

It’s easy to care about the wellbeing of the threatened giant panda because they’re cute.  But it’s hard to care about the critically endangered Chinese giant salamander, because they look like an enormous booger. 

Often conservation efforts focus on the cutest of the endangered species, but certain science groups are trying to find a way to choose which species to save without turning it into a beauty contest.

The Zoological Society of London uses a method called EDGE.

“There are lots of ways that conservation planners choose which species to save. The way the EDGE program uses is to prioritize the weird and wonderful species that represent the most evolutionary history on the tree of life. Things like platypuses that are weird and wacky and also represent millions of years of unique evolutionary history,” said Will Pearse, an evolutionary ecologist at Utah State University.

To rank animals using EDGE, researchers like Pearse use DNA sequences to figure out how related species are. An animal unrelated to others, like the platypus, gets a high score for evolutionary distinctness. The animals are ranked by how endangered they are. The result is a list of species from unusual and endangered – like the kakapo parrot – to common – like the pigeon.

Genetic data isn’t available for all species. When researchers tried to rank sharks, they only had access to DNA sequences for half of the species they were interested in.

Pearse’s research assistant Bodie Weedop explained:

“It’s very difficult for researchers to obtain a complete phylogeny," he said. "It’s very expensive and in some ways it might not be possible.  We might not be able to reach each individual species and sample them genetically. What we can do is build statistical models in order to address the missing species and assess them while not having sampled them.”

Pearse and Weedop are working to make models that can fix uncertainty in the family trees of species for the next release of EDGE.