The photos poured in from the Chihuahuan Desert to the Gulf of Mexico and through all the canyons in between, snapshots of a nearly 2,000-mile border now at the center of a potential government shutdown Friday.

For the better part of the last month, the scenes along the U.S.-Mexico border playing on cable television have featured migrants fleeing tear gas or climbing fences as President Trump escalates his demands that Congress fund the wall. But late Thursday, U.S. Rep. Beto O'Rourke, D-El Paso, who fell short last month in his Senate bid against Republican Sen. Ted Cruz, sought to offer an alternative vision.

RELATED: Amid growing apprehensions at border but no ‘caravan,’ a quiet Army set to depart Texas

"Where would they build the wall?" O'Rourke wrote on Twitter. "Whose home or ranch or farm are they going to take to build it? Which communities and habitats are they going to destroy?"

"Let the rest of the country see what's at stake," he said.

The dozens of photos that Twitter followers sent in response, featuring ankles dangling from cliffs in Big Bend National Park and kids wading in the Rio Grande, might as well have been a tourism ad for the border, leading some to pledge a visit or to "admit I had no idea how beautiful the border is." Some posted photos of the kayaking spot that "CHANGED MY LIFE!" or the spot where a grandfather once owned a ranch overlooking Mexico.

Where would they build the wall? Whose home or ranch or farm are they going to take to build it? Which communities and habitats are they going to destroy? Reply with your best pictures of the border - let the rest of the country see what’s at stake. pic.twitter.com/9ToIXXYKp2

— Beto O'Rourke (@BetoORourke) December 21, 2018



//

//

//

//

//

//

//



But while the photos are unlikely to sway congressional debate on the wall, they did illuminate some of the habitats most threatened by Trump's border wall, such as the Santa Ana National Wildlife Refuge and the National Butterfly Center in Texas. The Trump administration has been able to bypass dozens of environmental laws ranging from the Endangered Species Act to the Clean Air Act thanks to 1996 and 2005 legislation that gives precedence to border-security concerns. Earlier this month, the Supreme Court left in place a February ruling upholding the Trump administration's authority to waive the environmental rules, a major blow to groups seeking to save natural habitats along the border they fear will be destroyed by the president's wall.

O'Rourke's tweet, which drew close to 800 replies and more than 29,000 likes as of early Friday morning, gave voice to many of those who worry the ecotourism destinations will be irreparably harmed by the wall.

"I do not see where a wall would go without disrupting everything," wrote one woman, sharing video footage from a valley in Lajitas, west of Big Bend National Park.

"Couldn't imagine an ugly cement barrier running through this beautiful stretch of Texas," wrote one person from Big Bend National Park.

"It will destroy the National Butterfly Center, which is home to endangered monarchs as well as to a whole ecosystem of wildlife," said the actress Katharine Towne.

Of all those locations, the National Butterfly Center is perhaps imperiled most immediately. Funding for 33 miles of fencing in the Rio Grande Valley, where the center is located, was already approved as part of the $1.3 trillion omnibus spending bill in March, and construction on parts of the barrier is expected to begin in February.

Taken from the top of Lost Mine peak overlooking Mexico in the distance. A wall would endanger this land, the historic mountains, animals, plants, and more. pic.twitter.com/b5S4g8sPGo

— Kristen Hubby (@K_Hubbs) December 21, 2018



//

//

//

//

//





//

//

//

//

//



As the San Antonio Express-News reported earlier this month, the wall could be as tall as three stories high, consisting of 18-foot steel beams called bollards melded into a concrete base. It is expected to slash the 100-acre butterfly sanctuary by 70 percent, leaving most of the habitat on the Mexican side of the wall.

Luciano Guerra, an employee at the butterfly center and a Trump voter, wrote in a guest column for The Washington Post this week that "we dread the destruction that will come when the bulldozers arrive. ... That loud, heavy machinery will cause irreparable damage to the habitat we've worked so hard to restore." He said he fears that if the wall goes up, his grandchildren's "only experience of the Rio Grande Valley's natural beauty will be through the photographs I take today."

Nearby, the U.S. Fish and Wildlife Service tried to warn U.S. Customs and Border Protection about the environmental threats the border wall poses to animals and their habitats in the Lower Rio Grande Valley and Santa Ana National Wildlife Refuge. But Interior Department officials edited the Service's letter to remove some of those concerns so that CBP apparently never saw them, as The Post's Dino Grandoni and Juliet Eilperin reported last week, citing documents obtained through the Freedom of Information Act.

Biologists and wildlife managers for the Service said in a 2017 draft letter that the proposed 28-mile levee wall in Hidalgo County could leave animals trapped in the event of a wildfire or "catastrophic" flood, with the former being difficult to stop if a wall bisects the ecosystem. The levee wall would also have a 150-foot concrete enforcement area with bright floodlights, severely disrupting the habitats for nocturnal animals. Endangered species that live there, including the ocelot and jaguarundi cats, would be especially at risk, the scientists warned.

"The Lower Rio Grande Valley is a flood-prone area. The Service is concerned the levee wall in Hidalgo County could be subject to catastrophic natural flood events, leaving terrestrial wildlife trapped behind the levee wall to drown or starve," the Service wrote. "This project will likely cause widespread mortality for terrestrial organisms during catastrophic flood events."

But concerns about the trapped animals and wildfire hazards ultimately did not make it into the letter ultimately submitted to CBP, documents obtained by The Post showed.

For now the Santa Ana National Wildlife Refuge is safe; the omnibus spending bill in March included a provision specifically restricting the Trump administration from using the $1.7 billion for border security to go toward any wall construction there.

In October, the Department of Homeland Security issued a statement saying that although the agency is waiving various environmental laws to build the bollard wall in Hidalgo County, "DHS remains committed to environmental stewardship" and protecting wildlife.

Here's the U.S/Mex border at Organ Pipe Cactus National Monument. This is also the most imperiled wilderness area in the country, as #BorderPatrol cuts thousands of miles of wildcat roads through designated wilderness with no oversight. Now a target for more #BorderWall. pic.twitter.com/M7vgfR5o5U

— Laiken Jordahl (@LaikenJordahl) December 21, 2018



//

//

//

//



But whether Trump will ever have a chance to build his wall through other sensitive environments is unclear. The border wall is on shaky ground, with Democrats taking over the House next month. The GOP-controlled House passed a deal including $5.7 billion for the wall on Thursday, but the Senate looks unlikely to pass it Friday, potentially leading to a government shutdown.

On Tuesday, Trump appeared to suggest that those worried the wall will obstruct their views of nature should not be concerned. He said he'd build a wall that they could see through.

"The Democrats, are saying loud and clear that they do not want to build a Concrete Wall — but we are not building a Concrete Wall. We are building artistically designed steel slats, so that you can easily through it," he said, an apparent reference to the bollard wall.

"It will be beautiful," he added.

RELATED: Veteran draws millions in donations for Trump's border wall