#Real platypus growl plus#

But why is it like this in the first place, when two sex chromosomes work just fine? Do five Ys make the male platypus more sexy? Do the enforced combinations of Xes and Ys make the platypus more fit for survival? The answer to these questions is no. So there's how the platypus gets around this strange quirk of genetics. Once the egg and sperm meet, if there are 10 Xes, it’s female-and if there are 5 Xes and 5 Ys, it’s male. Depending on which one they take first, they'll produce sperm with five Xes, or sperm with five Ys. When they produce sperm, they take every *second* sex chromosome. They start in an alternating chain like this. So when the male sex chromosomes are forming into sperm, they pay special attention to the order they're in. but in terms of the percentage split of the Xes, there's nothing new here.īut with the males, you can see that the sex chromosomes can’t split at random, because then, you might get a platypus with 3 Ys and 7 Xes, or 1 Y and 9 Xes, and so on. There are a few caveats here, as you may notice that not all X chromosomes look the same. They only have Xes, so no matter which of those Xes they pass on, 100% of the sex chromosomes they pass on will be Xes, just like in humans. When it comes time to make a new platypus, the splitting of the female sex chromosome seems straightforward enough. And, again, like us, the female will have all Xes, and the male will have half Xes and half Ys. Like humans, their sex chromosomes are either X or Y. First, let's look at how their sex is determined. Just, why, platypus? But we'll get to that later. But there are only two sexes of platypus. That's 8 more total sex chromosomes than us.

#Real platypus growl plus#

They have 21 pairs of ordinary chromosomes, plus 5 pairs of sex chromosomes. It doesn't need to get any more complicated than that. When the egg and sperm meet, if the sperm carried an X chromosome, it's a girl. The sperm from the father will have 23 of his chromosomes, including either an X or a Y. The egg from the mother will have 23 of her 46 total chromosomes, including one of the two Xes from her sex chromosomes.

When we humans decide to make a baby human, the chromosomes split in order to create a new configuration with half from each parent. And if you have one X and one Y, you're male. One pair constitutes our sex chromosomes, which determine the sex we're born as. Our DNA is organised within 23 pairs of these little wiggly looking things-our chromosomes. Let's talk about platypus sex.įirst, though, a quick overview of sex chromosomes in humans. In addition to all of that, it has five times as many sex chromosomes as we humans do. And it's one of the only venomous mammals on the planet. Say hello to the platypus, one of the strangest animals in the world.