...A woman who admits to not liking cats!

Another stereotype bites the dust!

...especially as the vast majority of people who test positive for Toxo get it from eating raw meat. Women who are infected with it before getting pregnant are safe from abortions due to Toxo. And why did the author think it was so funny that someone's job (actually, many people's jobs) is a parasitologist. Parasitology is an important field which affects human health, animal health, and ecosystem health.

Really ridiculous. The author's bias and frank ignorance is all over this "article" - especially that last line about cats.

The author should really respect her audience more, especially as this article is in Broadsheet. Don't assume that we all share your surprise at the fact that - gosh! - can you imagine that someone studies gross things like worms? And ew, cat poop is gross? Quick, give me some smelling salts before I faint!

you would think this would show up as a big disparity in the male to female birth ratios.

Curious, I looked up cat populations. Did you know the US has the most cats of any country in the world? So many that if you discount China's 53 million cats (2nd place), the USA has more cats than the 3rd to 10th place nations PUT TOGETHER.

That is a lot of angry and frustrated women in the USA. No wonder man hatred is so universal in this country.

of scientific papers are a bit chaffing. A more thorough reading of the article reports only that the majority of women with very high loads of the toxoplasmosis parasite had boys. This does not mean that any woman exposed to toxoplasmosis is necessarily predisposed to bearing male offspring. Also, as pointed out by at least one previous commenter, the parasite wouldn't alter the child's sex but rather alter the success rate for male vs female fetuses. Your oversimplification of this issue places it only a step away from a bad email rumor --> playing with your cat will change your baby's sex...

and the author helpfully tells us:

"I also don't like cats."

What makes cat haters (kind of like Hillary haters) so compelled to share their little sickness with others, no matter its irrelevance to the topic at hand?

If it's been rejected by 8 journals, it's likely that 8 different groups of parasitologists have decided that his study is flawed and that his results don't mean anything. I.e. his conclusions are b.s.

People who get their papers rejected may like to pretend that they are persecuted geniuses, but most of the time a paper gets rejected multiple times, it's because it's total b.s.

What he said was specifically that the study had been rejected "usually without any formal review", which is more likely to mean they didn't find it relevant or interesting enough to publish in their specific journal. You only get rejected for scientific reasons after a journal has sent your paper out for review.

Of course, there is that "usually". This means at least one journal has rejected it through the peer-review process.

Thing is, if it's a one-off piece of data, without any real proposed mechanism, it's likely gonna be hard to find a journal that will publish it.

As for sex ratios, there's a slight M-F advantage at both conception and birth - 105 males for every 100 females. This being largely due to the fact that Y-bearing sperm have a slight advantage, being slightly faster swimmers. More males tend to die than females, evening out the sex ratios by age 15, and longer lifespans make the ratio about 72 men for every 100 women after the age of 65.

And, yup, to the person who said that the effect would have to be due to preferential miscarriage or some similar phenomenon, because the sperm ratios wouldn't be affected.

The NY Times had a frightening article about a year ago about toxoplasmosis, and how highly contagious it is. It infects approx. 50 million Americans, and about half the world's population. The parasite lives to get into a cat's gut, where it can procreate. It is present in warm blooded animals, so if your cat goes outdoors and eats birds, or other (uncooked!) wildlife, your cat has a pretty good chance of having toxoplasmosis. Then the egg-like cysts of the parasite are deposited in the litter box, or your yard where they survive for a year to infect the next host. Yikes! Yet another reason to keep cats indoors.

Just because it relates to gender doesn't mean it rates publication. This sounds like one of those things people circulate in email until it is refuted on snopes.com.

And we don't care what the author's opinion of cats is.

I changed a million cat pans during all my pregnancies, and I have five daughters. Though, as was so delightfully pointed out above, I never increased my chances by eating the box contents. Maybe that would have given my husband the son he's been wailing for for 12 years. Seriously, though, I often wonder if one gets a higher risk not from cleaning the box (I wash my hands very well afterwards) but from having cats crawl all over you, and rub on your face at night after they've been playing in the box all day. Ew.

such as hunting to feed our lazy gathering wives.

My understanding of the birthrate that favours male offspring is a genetic adaptation due to the fact that young men, because of testosterone, tend to do crazy things which tends to kill them at a young age, thus neccessitating the male:female birth ratio.

...and women with the parasite ARE having a lot more sons than daughters, isn't the parasite working by causing the women to miscarry the female embryos or fetuses?

The sex, after all, is determined by the sperm cell.

"of course his title is parasitologist! what did you think it would be?"

Well, I don't know about you, I for one was expecting it to be something in Czech, or maybe Slovak, like příživníkologist.

I am confused by the stated normal ratio - I always learned that females outnumbered males very slightly - that it was like a 51 F - 49M ratio in normal birthrates. Is that wrong, like everything else I was taught in scool?