We got Lisa at LAX and our photog asked her about the alleged alien corpses that were recently displayed during a UFO briefing for the Mexican government.

Lisa doesn't buy the idea human beings will unite as one if we are ever faced with irrefutable evidence of extraterrestrial lifeforms, and actually, it sounds like she thinks the opposite would unfold.

Basically, Lisa says our poor track record with animal extinctions on our planet means we will treat aliens like crap too ... and become even more divided.

Lisa's view jibes with what Neil deGrasse Tyson recently told us ... they're both predicting the discovery of alien life would not be some big kumbaya moment for all Earthlings.

While there seems to be mounting evidence we're not alone in the universe, Lisa's more focused on repairing our existing relationships with other terrestrial species we already interact with on the daily.