Gender bender Blue Crab 7/15/05

Here it is: the transgender crab: A blue crab that's half male (blue claw and washington bottom monument) and the other half female (red claw and dome of the capital building).

The story: David Johnson and Robert Watson of Middlesex County caught the crab off Gwynn's Island (Chesapeake Bay) on May 21, 2005.

Any good waterman knows that male crabs, called “jimmies,” have blue claws. Female crabs, called “sooks,” have red pinchers. “There was one male claw and one female claw,” Johnson said. In other words, one claw was blue and one claw was red. And that wasn't the most unusal thing about the crab.

Scientists at the Virginia Institute of Marine Science, were just as amazed at the crab, which they call a “bilateral gynandromorph” because its gender is literally split down the middle. Going through the scientific literature they discovered that a similar crab was caught near Smith's Island in Maryland in 1979. But this latest specimen is still alive, and may help scientists answer questions on the cloudy topic of crab sexuality.

Not only did the crab have reproductive organs of both genders, but its underside was shaped on one side like a female and on the other side like a male. A quick anatomy lesson: A jimmy’s bottom is shaped like the Washington Monument, and a sook’s bottom looks like the dome of the Capitol building.

True gender identity in the marine world isn’t as simple as it is with humans (atleast not to some humans). Some fish change gender during their lives (like some humans), however this crab was probably half male, half female from the point of conception. There are multiple potential causes (including the "homosexual agenda"). “We don’t know how many genes are involved or what the environmental factors (ie gay marriage) might be.”

The answers may come when scientists study the genetic makeup of the crab and its offspring. That’s right. They’re letting the creature breed. Waterman Johnson conducted his own experiment before handing the crab over to scientists. He put the crustacean in a floating tank with a female crab that was ready to mate.

At first the bi-gendered crab cradled the female crab, as if it was protecting it. That’s male behavior. But a day later, the crab let go and gobbled up half the female crab—a sign of female aggression in a species where cannibalism is common. “It was very confused on what to do,” Johnson said.

If you haven't figure it out yet, the words in italics are mine. I couldn't resist it.