“This body is going to continue to change as more people of a diverse background come,” Mr. Lewis said. “America is changing. We all need to get on board.”

But a generational divide could be emerging, especially with some African-American elders who have been in the House for decades. “I think they certainly bring a different perspective in some ways,” said Representative Danny K. Davis, Democrat of Illinois. “I think the wording sometimes is a little different. The level of what might be called ‘professional civility’ may be a little different, but I think the individuals are expressing in many ways the same feelings and are saying the same things.”

For the House Republican Conference, 90 percent of whom are white and male, some uncomfortable moments are inevitable. Mr. Meadows called the “birther” videos “old news” on Thursday and said he had previously apologized. He also appeared to reconcile with Ms. Tlaib; the two shared a hug and a seemingly cordial talk on the House floor.

“She said she didn’t mean it yesterday, so there was no need to apologize,” he told reporters afterward. “I wanted her to know, and she wanted me to know, that our relationship is one that will hopefully provide real good results going forward.”

Mr. Meadows and Ms. Tlaib are political and cultural opposites. Mr. Meadows, 59, a well-to-do real estate developer, is the chairman of the House Freedom Caucus and one of Mr. Trump’s most ardent defenders on Capitol Hill.

Ms. Tlaib, 42, made headlines on her first day in office after she was captured on video using an expletive to describe Mr. Trump as she spoke of her desire to impeach him. A lawyer and social justice advocate from Detroit, she is the daughter of Palestinian immigrants and one of the first two Muslim women in Congress.