The researcher says habitat isolation can lead to increased inbreeding and mutated genes.

A Houston biologist says a wall along the Texas-Mexico border would threaten wildlife.

Rice University’s Scott Egan says one concern is that the wall could impact some animals’ cross-border migration patterns. He says the concerns come from the study of other border barriers.

“There are scientists in China that study the ecological and evolutionary impacts of the Great Wall,” Egan says, adding that research from around the world has found that when humans split up habitat – through walls or other mean – there are consequences. Animals become isolated, they inbreed more, which leads to gene mutation.

Over the last few decades, black bears have naturally repopulated parts of the West Texas Big Bend region by crossing over from Mexico. Egan says that never would've happened with a wall.

“Scientists have worked on how isolated those bear populations are, and there could be additional effects by building a barrier wall which would allow them to not move back and forth for resources or to look for mates,” he says.

Egan says across the U.S.-Mexico border, a wall would threaten more than 100 endangered species.

The Trump Administration has signalled its willingness to skirt environmental reviews that are usually required. Homeland Security says it will bypass a handful of environmental and natural resource laws to speed up building part of the wall in California.