66: Gynandromorphy

Big word for a genetic mutation where an animal is split with one side being entirely female and the other male. This can happen in some species of birds, crustaceans, snakes, and insects.

Episode Transcript:

Welcome to Brain Junk, I'm Amy Barton and I'm Trace Kerr, and I want to share with you a Brain Storm about a gynandromorphy.

AB: I'm not sure how to feel about this topic at all.

TK: It's a huge word, isn't it? Don't be scared. It'll be okay. So I stumbled across this on Instagram with a picture of a cardinal. That's those all-red birds with a little black faces.

AB: This is a good direction. No forceps involved.

TK: Nope, no good direction. But the picture was strange in that half of the cardinal was bright red and the other half was light beige and...

AB: For real in real life?

TK For real for real. And I'm going to tell you why.

AB: Okay.

TK: So gynandromorphy is individual animals with both genetically male and female characteristics. So, and it can be bilateral, so cut straight and half or mosaic where like your arm is male and your face is female and this kind of thing. But it doesn't happen in mammals. It only occurs in insects, spiders, crustaceans, and very rarely birds.

AB: Can you imagine being the first guy that really documented that? They're like, no, we don't believe you buddy. I'm like, no, come and look! For real! 
TK: Well, here's how it happens. So this is according Natural History Magazine in insects and birds. So, in humans, a woman's egg is, you know is one, it's the x, okay? And the sperm has x or y. So they get together and you have an x, x, which is female or x, y, which is male. Well, in birds, the egg can have a z male or a w female, and the male is only donating a z cell. So here's what's weird. If the egg has both a z and a w, and if the male for some reason has a zz sperm, that egg is going to get fertilized and you will have both female and male cells growing in one egg. Ooh. So knowing how often it happens is tough to know because we really only notice when the animal had happens in has sexual dimorphism, which is the male and female look different. So if you have a cardinal, the male is bright red, the female is light beige.

AB: So this would be like one baby, little tiny man fish, really big lady fish.

TK: Yup. And uh, like in lobsters there's this great picture where one side of this lobster, it's like somebody drew a line right down the middle of one side is bright orange and one side is dark black.

AB: Huh? Weird.

TK: Yeah. And then in the cardinals there was a story about one on the BBC and it's sang like a male, but was being courted by another male. And depending on how its insides are all set up, this bird could actually reproduce.

AB: Wow.

TK: Yeah. Depending on which, where all the anatomy broke down, if it was, if it was more mosaic, he inside and it has, you know, the capability to have eggs then yeah, it could possibly breed.
AB: Wow.

TK: Yeah. I also found a rose gypsy moth where the wings on the female side are half the size and brown and gray and the male side is pink on the wings and abdomen.

AB: Was it able to fly? Was at disproportionate enough that it could,

TK: It probably couldn't fly because you know, these female wings were super tiny and the male were super big.

AB: Always going in circles.

TK: Yes. It just kind of flutters around.

AB: Now, this is not a thing that happens in mammals you said. So like you see the picture of the dog with black fur and a blue eye and then uh...

TK: Now that is a Chimera and that's not male and female. What's happened there is you have two cells, two different developing embryos that stuck together and...

AB: So you're your own twin?

TK: Yes, you have two different people. So like this is going completely off topic, but it's fascinating. A woman had children and then they found out later that those children were her sister's children. She did not have a sister. She was part herself and Part, her sister and the ovary that these children had come from came from her sister's ovary.

AB: That is crazy.

TK: Right?

AB: Wow.

TK: So we have the Chimeras and then we could also have someone who is intersex that's completely different from this. This is, this is a creature who is actually half male and half female and a completely different way.

AB: Wow. My brain will catch on and be like, I'm totally getting this. And then I'm like, oh, derailed.

TK: And I'll get a text at nine 45 tonight and I'll have to explain it. Yeah.

AB: Is it divided left to right or front to bacK?

TK: It could be any way.

AB: So complicated!

TK:I know, and that's your Brain Storm. 

AB: We should've done this one last. My brain is a little fried now.

AB: We're on Facebook and Instagram as BrainJunkPodcast, and you can find us on Twitter as @MyBrainJunk. Trace and I will catch you next time when we share more of everything you never knew you wanted to know. And I guarantee you will not be bored.