Even people who otherwise support transgender equality often draw the line at transgender women competing against cisgender women. We have a couple of new opinions expressed lately. What makes these more unusual than most is that they are grounded in science.

Steven Petrow investigates at Washington Post.

This charged debate is timely because of a landmark rule change instituted by the International Olympic Committee (IOC) this year. In Rio, transgender men (female-to-male athletes) will be allowed to compete without any restrictions (based on the sexist assumption, I suppose, that trans men could never dominate their sports). Trans women, meanwhile, are no longer required to undergo gender-reassignment surgery to compete in female divisions, and the previously mandated two-year wait after transitioning has been jettisoned.

Opening Ceremonies at the 2016 Olympics in Rio are this evening at Maracana Stadium...even though we are already through two days of Soccer competition.

The show was produced by film director Fernando Meirelles (City of God).

I hope that the Opening Ceremony will be a drug for depression in Brazil.

--Meirelles

Rumors are flying. Some of them are true.

Lots of samba and bossa nova. Lots of dancers. Mrs. Tom Brady, Brazilian super model Giselle Bundchen as the Girl from Ipanema.

Two transgender women have been selected to important roles at the Democratic National Convention this week.

Of course you are aware that around the country there are legislative efforts to force transgender people to use the bathroom and locker rooms reserved for the sex we were assigned at birth. In some places, it is phrased rather as requiring those facilities to be segregated by chromosomes.

Awkward, that. As a society, we have never determined assignment of sex at birth by a test of chromosomes. I'm 68 years old and, as far as I know, I have never had my chromosomes tested. Ever.

I find it stranger still that the forces calling for this anti-transgender discrimination have such little regard for science in general. These are people who believe the universe was created between 6000 and 7000 years ago, that a woman was created from the rib of a man, and that Jesus rode to Sunday School on the back of a dinosaur.

The Chicago Tribune's Steve Chapman explains the problem with jokes about being transgender.

When I was a lad, I often heard jokes about blacks, Latinos and gays, who were regarded as amusing because of their supposed inferiority and defectiveness. Today most people would be embarrassed and offended by such humor. But, at least in some places, there is one group that is still a safe source of yuks: transgender people.

--Chapman