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Gynandromorphs (Sexual Chimeras; One Body / Both Sexes)

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CygnusRex

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(Transplanted from the Gay Animals thread)

Part Male, Part Female, Fully Mysterious
Dual-Sex Crab Found in Bay Could Yield Clues to Species' Genetics and Mating Habits

By David A. Fahrenthold
Washington Post Staff Writer
Thursday, June 16, 2005; Page B01

Watermen say that female blue crabs "paint their fingernails," meaning the tips of their claws turn bright red as they age. The male crabs, on the other hand, have sky-blue claws -- a sign as masculine as a mustache in the world of crustaceans.

So when Robbie Watson dumped out a crab trap and found a specimen with one red claw and one blue one, the discovery stopped him.

"I set it aside for a while," Watson said. "I really wasn't sure what to think."

As his boat, the Wharf Rat, moved on to other crab pots, Watson, 42, studied the crab. Underneath, its shell should have had a design looking roughly like the U.S. Capitol dome if it were female, or a Washington Monument pattern if it were male.

Instead, Watson found a wavy arrow, which seemed to be a combination of both sexes.

"It was unreal," Watson said. "I've never seen anything like that, and I've worked the water all my life.''

Scientists said the crab, caught May 21 near Gwynns Island in the lower bay, is an extremely rare creature called a "bilateral gynandromorph" -- that is, split between two genders -- with its right side female and its left side male.

The last time such a crab was caught in the Chesapeake region was about 1980, scientists said. Since then, watermen have hauled in millions of crabs annually without noticing another.

On the day they caught it, Watson and boat captain David Johnson had been crabbing since about 5:30 a.m., dumping females into one basket and males -- who are often bigger and sell for twice as much -- in another.

"What basket should we put it in?" Watson asked the captain.

"I think we're going to put it in one up front," Johnson, 50, recalled telling him.

They covered it with a wet rag to keep it alive.
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Source: http://www.washingtonpost.com/wp-dyn/content/article/2005/06/15/AR2005061502231.html
 
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A half-male, half-female butterfly has hatched at London's Natural History Museum.

A line down the insect's middle marks the division between its male side and its more colourful female side.

Failure of the butterfly's sex chromosomes to separate during fertilisation is behind this rare sexual chimera.

Once it has lived out its month-long life, the butterfly will join the museum's collection.

Only 0.01% of hatching butterflies are gynandromorphs; the technical term for these strange asymmetrical creatures.

"So you can understand why I was bouncing off of the walls when I learned that... [it] had emerged in the puparium," said butterfly enthusiast Luke Brown from London's Natural History Museum.

Mr Brown built his first butterfly house when he was seven, and has hatched out over 300 thousand butterflies; this is only his third gynandromorph.
Half and half

It is not only the wings that are affected, he explained. The butterfly's body is split in two, its sexual organs are half and half, and even its antennae are different lengths.

"It is a complete split; part-male, part-female... welded together inside," he told the BBC.

The dual-sex butterfly is an example of a Great Mormon, Papilio memnon - a species that is native to Asia.

With a shortage of butterfly-specific gender neutral pronouns, the butterfly is being referred to as "it", and is already middle-aged at three and a half week's old.

So the public has only a narrow window of opportunity to see it alive.

Though rare, gynandromorphy isn't unique to butterflies; individual crabs, lobsters, spiders and chickens have all been found with a mix of two sexes.

There are likely many more cases in the natural world, but sexual chimeras are more difficult to spot in animals where females and males look alike.

BBC Source (with photo)
 
Sorry, didn't know where to put this, so created a new thread. Mods - feel free to move this to an already-existing thread...

Split-colour bird is half male, half female

Remotely-linked image is now MIA. Here is another version of the cardinal photo that appeared with the cited article.

Gynandromorph-Cardinal.jpg
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I don't see any problem with quoting the text too:

No, this bird didn't dye its feathers. The half-red, half-white plumage of this northern cardinal (Cardinalis cardinalis) is the result of gynandromorphy. In other words its sex chromosomes did not segregate properly after fertilisation, so the bird is half-male, half-female. Males are usually bright red all over while females are a more subdued white, but due to the developmental quirk, the bird's colours are split down the middle.

Cardinals with such plumage are rare so Brian Peer from Western Illinois University in Macomb and colleague Robert Motz observed it for over a year. They found that although the bird never found a mate and never belted out its characteristic trilling song, at least other birds didn't target it for its unusual looks.

Journal reference: The Wilson Journal of Ornithology DOI: 10.1676/14-025.1
 
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That's a beautiful animal :)
 
Here's a newly publicized example among the bees ...
Scientists Find a Half Male, Half Female Bee, Split Right Down The Middle

Every now and again, though, nature throws a curveball - producing an organism that's a combination of both sexes, divided straight down the middle.

This condition is known as gynandromorphism, and scientists have just found the first known gynandromorphic individual of its species in a nocturnal bee native to Central and South America, Megalopta amoenae.

On its left side, the bee is physiologically male. It has a small, dainty mandible, a long antenna, and a thin, delicate hind leg with fewer bristles. The right side has female characteristics - a shorter antenna, a pronounced, toothed mandible, and a thick, hairy hind leg.

It's a known phenomenon - gynandromorphs have been found in at least 140 bee species, as well as butterflies, birds and crustaceans (but virtually unknown in mammals). In bees at least, it's usually only seen after the insect is already dead, and in a museum.

In this case, researchers led by entomologist Erin Krichilsky of Cornell University were conducting a study on circadian rhythms in M. amoenae, and were working with living bees from the forest of Barro Colorado Island in Panama at the Smithsonian Tropical Research Institute. ...

There are aspects of bee gynandromorphism we are starting to understand very well. A 2018 study, for instance, was able to shed some light on how they come to exist in honeybees.

Sex determination in Hymenoptera - the order of insects that includes bees, ants and butterflies - is really peculiar. If an egg is fertilised? You get a female. An unfertilised egg produces a male. But, as the 2018 research found, if sperm from a second and even third individual enters an egg that's already fertilised - a female embryo - it can divide to produce male tissue, resulting in a gynandromorph.

A handful of studies have focused on different areas of behaviour in live gynandromorphic bees - nesting behaviour and courtship. Since this team was already studying circadian rhythms - which synchronise a species' behaviour and interactions with the external environment - they decided to see if and how circadian rhythms differed in their gynandromorphic individual. ...
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FULL STORY: https://www.sciencealert.com/this-bee-is-half-male-and-half-female-split-right-down-the-middle
 
Researchers banding songbirds in Pennsylvania recently discovered a gynandromorphic grosbeak.

gynandromorph-grosbeak.jpg

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This rare bird is male on one side and female on the other

Male rose-breasted grosbeaks have some red-pink feathers while females’ are yellow and brown

In Rector, Pa., researchers have spotted one strange bird.

This rose-breasted grosbeak has a pink breast spot and a pink “wing pit” and black feathers on its right wing — telltale shades of males. But on its left side, the songbird displays yellow and brown plumage, hues typical of females.

Annie Lindsay had been out capturing and banding birds with identification tags with her colleagues at Powdermill Nature Reserve in Rector on September 24 when a teammate hailed her on her walkie-talkie to alert her of the bird’s discovery. Lindsay, who is banding program manager at Powdermill, immediately knew what she was looking at: a half-male, half-female creature known as a gynandromorph.

“It was spectacular. This bird is in its nonbreeding [plumage], so in the spring when it’s in its breeding plumage, it’s going to be even more starkly male, female,” Lindsay says. The bird’s colors will become even more vibrant, and “the line between the male and female side will be even more obvious.” ...

Such birds are rare. Lindsay has seen only one other similar, but less striking, bird 15 years ago, she says.

Gynandromorphs are found in many species of birds, insects and crustaceans such as crabs and lobsters. This bird is likely the result of an unusual event when two sperm fertilize an egg that has two nuclei instead of one. The egg can then develop male sex chromosomes on one side and female sex chromosomes on the other, ultimately leading to a bird with a testis and other male characteristics on one half of its body and an ovary and other female qualities on the other half.

Unlike hermaphrodites, which also have genitals of both sexes, gynandromorphs are completely male on one side of the body and female on the other.

Scientists don’t know if these birds behave more like males or females, or if they can reproduce. ...

In 64 years of bird banding, Powdermill’s Avian Research Center has recorded fewer than 10 such birds. ...
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FULL STORY: https://www.sciencenews.org/article/bird-male-female-grosbeak-gynandromorph
 
Rare bird: 'Half-male, half-female' cardinal snapped in Pennsylvania

A bird that appears to be half-female and half-male has been photographed in Pennsylvania by a birder who rushed out with his camera when he heard a friend had spotted the northern cardinal.

Though not unheard of, mixed sex birds are rare.

Male cardinals are bright red but females are pale brown, suggesting this specimen may be a mix of the two sexes.

_117215349_cardinal5.jpg


https://www.bbc.com/news/world-us-canada-56189600
 
Souleater said:
Rare bird: 'Half-male, half-female' cardinal snapped in Pennsylvania

A bird that appears to be half-female and half-male has been photographed in Pennsylvania by a birder who rushed out with his camera when he heard a friend had spotted the northern cardinal.

Though not unheard of, mixed sex birds are rare.

Male cardinals are bright red but females are pale brown, suggesting this specimen may be a mix of the two sexes.

View attachment 35893

https://www.bbc.com/news/world-us-canada-56189600
Click to expand...
It's a "gynandromoph":
https://www.sciencenews.org/article/bird-male-female-grosbeak-gynandromorph

Gynandromorphs are found in many species of birds, insects and crustaceans such as crabs and lobsters. This bird is likely the result of an unusual event when two sperm fertilize an egg that has two nuclei instead of one. The egg can then develop male sex chromosomes on one side and female sex chromosomes on the other, ultimately leading to a bird with a testis and other male characteristics on one half of its body and an ovary and other female qualities on the other half.

Unlike hermaphrodites, which also have genitals of both sexes, gynandromorphs are completely male on one side of the body and female on the other."
 
Now, just apply the gynandromorph system to your next Potato Head project, and you'll be all up to date on the pop news of the day.
 
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