Acclaimed astrophysicist Neil deGrasse Tyson is under fire after conservatives uncovered footage of him alleging that chromosomes are insufficient when it comes to determining a person’s gender because identity is a choice.

“Apparently, the XX/XY chromosomes are insufficient because when we wake up in the morning, we exaggerate whatever feature we want to portray the gender of our choice, either the one you’re assigned, the one you choose to be, whatever it is,” Tyson told sports television personality Stephen A. Smith in a May interview.

The United States is a land that values the pursuit of happiness, Tyson argued.