Rare Intersex Southern Right Whale Discovered Through Genetic Testing

0:00 We're going to be talking about an interesting discovery on today's episode of the how to protect the ocean podcast. We're gonna be talking about intersex marine mammals. That's right. We're gonna be talking about marine mammals that have the X XY chromosome because there was a new discovery that came out in a paper where marine biologists did a genetic test and found that a southern right whale that was sampled back in 1989 has X XY chromosomes. This is very rare in marine mammals. It's something that we have to talk about and we're going to talk about today. So let's start the show. Hey everybody, welcome back to another exciting episode of the how to protect the ocean podcast. I'm your host, Andrew Lewin. And this is a podcast where you find out what's happening with the ocean, how you can speak up for the ocean, what you need to do to live for a better ocean by taking action on today's episode, we're going to be talking about all things marine mammals and genetic testing and what in the world is an intersex organism. This is going to be a lot of fun. I know there's a lot of political debates around this and political talk around what is intersex? What's transgender? What is all this stuff around, you know, different types of genders and stuff.

1:04 This is not the case. It's not one of those topics. We are going to be talking about intersex. This is not the same as transgender. This is not the same as anything that we're just talking about genetic material that has XXY chromosomes. Normally, XX chromosomes, a female XY chromosome is a male. So we're talking about animals that have the genetic material of XXY as well as some have noticeably seen having different both reproductive organs present at the time of death when they're actually in the crops because that's when we actually see what is happening. So we're going to talk about that today. Like I said, this is not a political thing. This is just what we discovered in science. I want to get that right up there because I know people in the comments are going to be like, you're just pushing an agenda that says nothing to do with any political agenda.

1:50 This is science. This is what's been discovered and what I think is something that's pretty cool to help us understand these animals. We're going to just talk about, you know, how this all came to be. So 1989, researchers collected skin samples from southern right whales off the Argentina's Valdez Peninsula to study the species genetic diversity. So they're just looking at genetic diversity. Decades later in 2022, Carla Crossman, a graduate student from St. Mary's University in Halifax, Nova Scotia, go Canada, analyzed these samples and encountered an anomaly with one whale labeled EAU10B. This initial chromosome analysis suggested that EAU10B was female possessing two X chromosomes, which is typical of females. However, further testing revealed the presence of the SRY gene typically found in Y chromosome and associated with male development.

2:38 So doing even more further testing and figuring out that there is a Y chromosome, they just found out this individual has a chromosome configuration of XXY identifying it as the first documented intersex southern right whale. This is pretty cool. And it's very rare to find these types of intersex individuals in marine mammals because we don't really get to see and get a lot of genetic testing in marine mammals. Although further research has discovered that we can take more tissue samples and stuff, but it's very difficult to work with marine mammals for obvious reasons. They're not a lot in captivity. A lot of them are in the wild. It's very difficult to get samples in general. We're just discovering patterns of the species and really getting to know those species. So more genetic testing, I'm sure, will reveal this if it's tested. The one thing in this study, which was found in Nautilus magazine, by the way, I'll put the link in the show notes.

3:24 It was interesting to see that a lot of animals are tested for, say, the double X chromosome if they think that they're a female or a male. And then once you know that there's two X chromosomes, you don't do any further testing. It wasn't until Carla figured, hey, look, there's something here that suggests that this may also be male. And so they did further testing, tested for that Y gene and found out that is double X Y. That's a really cool thing to do. It doesn't happen often. It just goes. I wonder how many individuals that we missed that could have been intersex, but we didn't further test. Right. We just tested for one side. We said, oh, it's got an X Y chromosome or it's got a double X chromosome. It must be females, must be male, depending on the chromosome configuration. Really simple stuff. Sometimes it's missed in science because, you know, why bother with that? You just assume that's going to happen. This is why we test as we continue to test.

4:08 So kudos to Carla for doing that and really opening the eyes of other scientists to be like, hey, maybe we do see more intersect individuals, but we just don't know. We just don't test for them. So maybe that will be something to test for in the future as well as the other samples that have been preserved of that population to see if that is something that is normal. Now these species that are intersect tend not to be reproductive. So some of the reproductive organs that have been seen in the past, like in bottlenose dolphin, they're not. They've been seen in porpoises. They've been seen in seals often have both reproductive organs, but they're not fully developed. So indicating that they're not reproductive. However, we don't know if they're actually reproductive or not. We just assume based on the development that we see in front of us and scientists see in front of us. I've never done this type of study before. That's why I'm talking about it because I think it's kind of cool. But so that's something that we need to find out more about. Right.

4:57 Because intersect species have been around for quite some time. We've seen them in freshwater systems are actually prolific. Freshwater systems are actually very important. Freshwater systems are actually prolific freshwater systems studies by the US Geological Survey revealed that the male smallmouth bass in Pennsylvania is Suska Hana. Suska Hana. I think it's Suska Hana. Maybe I'm not sure the pronunciation of that. I apologize in Delaware and Ohio River basins exhibited immature eggs in their testes. This intersex condition is believed to result from exposure to endocrine disrupting chemicals. So things that happen in the environment such as pesticides and hormones that enter waterways through agricultural runoff and water. Through agricultural runoff and wastewater discharges. So amphipods and environmental stressors have also been discovered. So in the marine environment intersects occurrences have been observed in species like the amphipod. The Aquino Gameras marineis long term monitoring in Northwest Brittany recorded intersex individuals and frequencies ranging between 0.87% to 12%.

5:51 Notably the incidence of intersex increase with distance from the sea. Suggested environmental factors including endocrine disrupting compounds and freshwater stressors may play a role in triggering intersex conditions. So again being close to humans not always great for animals. So having those endocrine disruptors present can really change somebody and change an animal. We're not just being facetious with that. That's just not me saying that. That's true. This is what the evidence kind of shows. So we know that there are animals that are out there in the marine environment that will change sexes depending on the environment. So some fish like clownfish will change their sex if there's no other females around. So a male will turn to a female so that it can reproduce and it can have babies.

6:34 The survival of the fittest is the genetic material that continues to persist in clownfish that allows them to survive for so long. So if it's just males that are around and there are no females one male will turn into a female and then that female will reproduce with all the males and then you know they'll have their babies their larva and it'll grow into some lots more clownfish. It's really interesting to hear these different types of evolutionary factors that help animals survive in the environment whether it's a freshwater or marine environment. So that's always something that is interesting. Now there are different ways to detect intersex. So it could be from genetic material which doesn't always happen or it could just be from mixed animal tissue such as ovarian and testicular tissue within the actual bodies.

7:17 The individuals have either underdeveloped or nonfunctional reproductive organs which suggest they are unlikely to produce. The EAU 10B which is the intersex southern right whale that really capped off this story discovered in 1999. They had the XXY chromosomal set up but there's no indication that it reproduced and this chromosomal combination is typically associated with infertility and other mammals including humans. So this is not just something that happens in southern right whales or in southern right whales. It can actually happen in intersects in fin whales was reported with both seses and uterus but no functional reproductive output was recorded in harbor purposes as I mentioned earlier some intersex individuals had both male and female tissue but again no evidence supporting that reproduction was found.

7:59 So it's a hard thing to find out because we don't really see when males and females reproduce on the regular. We do have that video that I talked about a couple months ago where you know somebody caught it on photographs a series of photographs of two humpback whales reproducing mating off the coast of Maui and so that was kind of cool to see. But we don't often get that and a lot of times the intersex conditions are only discovered after death during the crop seas. So scientists rarely have a chance to study the behavior or reproduction over time. So it's really difficult to see. But I just think that's a good thing. I just thought it was a cool thing to bring to you as a way to understand species understand what is happening in the oceans how we are affecting the oceans and how we're affecting the species that live in it through disrupting endocrine systems that can change the hormonal balance within animals but also the way they naturally evolve into being able in some species being able to change from male to female and there's also the case of pharmaceuticals which again probably endocrine disruptors that get into our river systems just from what we've been ingesting.

8:57 Right. This is like typical stuff that we ingest whether it be you know pain pills whether it be reproductive blocking pills or anything like that that can go through our system and that will actually end up in the river systems like through a plumbing in the river systems that can affect fish that's why we see a lot of freshwater fish being affected by this either intersex or other type of I say just differences in morphologies. So it's a cool study to look at. It's really great to identify and talk about it. We're only just scratching the surface with this type of stuff as we normally are when we're discovering something new. But I thought it was really great to bring it to you. I'd love to hear your thoughts on this. Leave a comment below if you're watching this on YouTube. And if you are listening to this on another platform, please hit me up on Instagram at how to protect the ocean. That's at how to protect the ocean. I want to thank you so much for joining me on today's episode of the how to protect the ocean podcast. Have a great day. We'll talk to you in a happy conservation.