Yes, it can be very overconfident. Once contrary information is pointed out, it sometimes doubles down, denying it is wrong, sometimes retreats to saying it’s just a language model that doesn’t know anything, and sometimes alters its answers to correct its mistake.
Here’s one I tried (I’m not a biologist, but I think I know enough to tell what’s right here). Note how it is very confident that crossing over almost never occurs between X and Y chromosomes, inventing some fictitious evidence, but after I mention “pseudoautosomal regions” it switches without comment to acknowledging that crossing over between X and Y not only occurs, but is essential, presumably because this keyword activates some associations that were previously not seen. It would be interesting to know whether its initial confidence reflects some human training text that is similarly confident but mistaken, or whether it has itself actually deduced (mistakenly) that there’s no crossing over because of the size difference (which would actually be fairly impressive, even though wrong, though inventing fictitious evidence is going too far). Note that the two incorrect answers before the right one sound quite plausible, and I think would be readily accepted by people who have no specific knowledge of this topic.
Radford Neal Does crossing over occur between the X and Y chromosomes in human males?
Crossing over does not typically occur between the X and Y chromosomes in human males. The X and Y chromosomes are the sex chromosomes in humans, with the X chromosome being inherited from the mother and the Y chromosome being inherited from the father. During meiosis, the X and Y chromosomes pair up with each other, along with the 22 pairs of autosomes, or non-sex chromosomes. However, because the X and Y chromosomes are significantly different in size and composition, they are not able to exchange genetic material through the process of crossing over.
This lack of crossing over between the X and Y chromosomes has important implications for human genetics. Because the X and Y chromosomes do not undergo crossing over, the genetic information they contain is not shuffled or mixed, and the genes on the X and Y chromosomes are inherited in a more predictable manner than the genes on the autosomes. This can affect the likelihood of certain genetic conditions, such as sex-linked disorders, which are caused by mutations on the X or Y chromosomes and are more common in males than in females. Additionally, the lack of crossing over between the X and Y chromosomes can have important evolutionary consequences, as it can limit the potential for genetic variation on the sex chromosomes and affect the rate at which new genetic traits can arise.
Radford Neal I understand that most of the X chromosome can’t be exchanged with the smaller Y chromosome, but are there any parts of the X and Y chromosomes that can be exchanged?
Crossing over between the X and Y chromosomes is extremely rare in human males, and it is not known to occur in any significant way. The X and Y chromosomes are the sex chromosomes in humans, with the X chromosome being inherited from the mother and the Y chromosome being inherited from the father. During meiosis, the X and Y chromosomes pair up with each other, along with the 22 pairs of autosomes, or non-sex chromosomes. However, because the X and Y chromosomes are significantly different in size and composition, they are not able to exchange genetic material through the process of crossing over.
There is some evidence to suggest that crossing over between the X and Y chromosomes may occur in a very limited way in some individuals, but this is extremely rare and has not been observed in any significant way. In general, crossing over between the X and Y chromosomes is not thought to occur in human males, and the genetic information on the X and Y chromosomes is inherited in a more predictable manner than the genes on the autosomes. This can affect the likelihood of certain genetic conditions, such as sex-linked disorders, which are caused by mutations on the X or Y chromosomes and are more common in males than in females. Additionally, the lack of crossing over between the X and Y chromosomes can have important evolutionary consequences, as it can limit the potential for genetic variation on the sex chromosomes and affect the rate at which new genetic traits can arise.
Radford Neal I thought there were portions of the X and Y chromosomes at the ends called “pseudoautosomal regions” where crossing over does occur.
You are correct that there are portions of the X and Y chromosomes called pseudoautosomal regions (PARs) where crossing over is known to occur. The PARs are located at the ends of the X and Y chromosomes, and they are composed of DNA sequences that are similar to those found on the autosomes. Because of their similar composition, the PARs are able to undergo crossing over, allowing for the exchange of genetic material between the X and Y chromosomes.
The PARs are important for several reasons. First, they allow for the exchange of genetic material between the X and Y chromosomes, which can help to maintain the genetic diversity of the sex chromosomes. This is important because the lack of crossing over between the X and Y chromosomes can limit the potential for genetic variation on the sex chromosomes, which can have negative effects on the evolution of the species. Additionally, the PARs are important for the correct segregation of the X and Y chromosomes during meiosis, which is essential for the production of healthy gametes. By undergoing crossing over, the PARs help to ensure that the X and Y chromosomes are accurately distributed to the daughter cells during meiosis, allowing for the production of genetically diverse gametes. Overall, the PARs are an important part of the X and Y chromosomes, and they play a crucial role in the process of meiosis and the maintenance of genetic diversity.
Yes, it can be very overconfident. Once contrary information is pointed out, it sometimes doubles down, denying it is wrong, sometimes retreats to saying it’s just a language model that doesn’t know anything, and sometimes alters its answers to correct its mistake.
Here’s one I tried (I’m not a biologist, but I think I know enough to tell what’s right here). Note how it is very confident that crossing over almost never occurs between X and Y chromosomes, inventing some fictitious evidence, but after I mention “pseudoautosomal regions” it switches without comment to acknowledging that crossing over between X and Y not only occurs, but is essential, presumably because this keyword activates some associations that were previously not seen. It would be interesting to know whether its initial confidence reflects some human training text that is similarly confident but mistaken, or whether it has itself actually deduced (mistakenly) that there’s no crossing over because of the size difference (which would actually be fairly impressive, even though wrong, though inventing fictitious evidence is going too far). Note that the two incorrect answers before the right one sound quite plausible, and I think would be readily accepted by people who have no specific knowledge of this topic.
Radford Neal
Does crossing over occur between the X and Y chromosomes in human males?
Crossing over does not typically occur between the X and Y chromosomes in human males. The X and Y chromosomes are the sex chromosomes in humans, with the X chromosome being inherited from the mother and the Y chromosome being inherited from the father. During meiosis, the X and Y chromosomes pair up with each other, along with the 22 pairs of autosomes, or non-sex chromosomes. However, because the X and Y chromosomes are significantly different in size and composition, they are not able to exchange genetic material through the process of crossing over.
This lack of crossing over between the X and Y chromosomes has important implications for human genetics. Because the X and Y chromosomes do not undergo crossing over, the genetic information they contain is not shuffled or mixed, and the genes on the X and Y chromosomes are inherited in a more predictable manner than the genes on the autosomes. This can affect the likelihood of certain genetic conditions, such as sex-linked disorders, which are caused by mutations on the X or Y chromosomes and are more common in males than in females. Additionally, the lack of crossing over between the X and Y chromosomes can have important evolutionary consequences, as it can limit the potential for genetic variation on the sex chromosomes and affect the rate at which new genetic traits can arise.
Radford Neal
I understand that most of the X chromosome can’t be exchanged with the smaller Y chromosome, but are there any parts of the X and Y chromosomes that can be exchanged?
Crossing over between the X and Y chromosomes is extremely rare in human males, and it is not known to occur in any significant way. The X and Y chromosomes are the sex chromosomes in humans, with the X chromosome being inherited from the mother and the Y chromosome being inherited from the father. During meiosis, the X and Y chromosomes pair up with each other, along with the 22 pairs of autosomes, or non-sex chromosomes. However, because the X and Y chromosomes are significantly different in size and composition, they are not able to exchange genetic material through the process of crossing over.
There is some evidence to suggest that crossing over between the X and Y chromosomes may occur in a very limited way in some individuals, but this is extremely rare and has not been observed in any significant way. In general, crossing over between the X and Y chromosomes is not thought to occur in human males, and the genetic information on the X and Y chromosomes is inherited in a more predictable manner than the genes on the autosomes. This can affect the likelihood of certain genetic conditions, such as sex-linked disorders, which are caused by mutations on the X or Y chromosomes and are more common in males than in females. Additionally, the lack of crossing over between the X and Y chromosomes can have important evolutionary consequences, as it can limit the potential for genetic variation on the sex chromosomes and affect the rate at which new genetic traits can arise.
Radford Neal
I thought there were portions of the X and Y chromosomes at the ends called “pseudoautosomal regions” where crossing over does occur.
You are correct that there are portions of the X and Y chromosomes called pseudoautosomal regions (PARs) where crossing over is known to occur. The PARs are located at the ends of the X and Y chromosomes, and they are composed of DNA sequences that are similar to those found on the autosomes. Because of their similar composition, the PARs are able to undergo crossing over, allowing for the exchange of genetic material between the X and Y chromosomes.
The PARs are important for several reasons. First, they allow for the exchange of genetic material between the X and Y chromosomes, which can help to maintain the genetic diversity of the sex chromosomes. This is important because the lack of crossing over between the X and Y chromosomes can limit the potential for genetic variation on the sex chromosomes, which can have negative effects on the evolution of the species. Additionally, the PARs are important for the correct segregation of the X and Y chromosomes during meiosis, which is essential for the production of healthy gametes. By undergoing crossing over, the PARs help to ensure that the X and Y chromosomes are accurately distributed to the daughter cells during meiosis, allowing for the production of genetically diverse gametes. Overall, the PARs are an important part of the X and Y chromosomes, and they play a crucial role in the process of meiosis and the maintenance of genetic diversity.