Eat Your Breakfast to Have a Son

This is interesting. Confirmation of something which has been seen in other species but not (at least as far as I know) in humans.

The first evidence that women can influence the sex of their child by what they eat before they become pregnant is published today.

The study, which links higher energy intake around conception to the birth of sons, provides the first explanation of why the number of boy babies is in decline in the west, suggesting it is the result of women consuming low fat foods and skipping breakfast, among other things.

In times of plenty, more sons are born, in hard times, more daughters. The reason is:

The work complements studies of other animals that shows that more sons are produced when a mother has plentiful resources or is high ranking, reflecting how boys are more taxing to raise.

"Boys breast feed for longer and for more," she says. "There is evidence from traditional societies that mothers invest more time in bringing up boys. And if a mother has plentiful resources then it can make sense to invest in producing a son because he is likely to produce more grandchildren than would a daughter. However, in leaner times having a daughter is a safer bet."

The phenomenon, where lean times are linked with daughters, has been most extensively studied in insects, but is also seen in horses, cows and some species of deer.

Dr Mathews adds: "Potentially, males of most species can father more offspring than females, but this can be strongly influenced by the size or social status of the male, with poor quality males failing to breed at all.

Females, on the other hand, reproduce more consistently. The mechanism is not yet understood in mammals, but it is known from IVF research that high glucose levels encourage the development of male embryos while inhibiting female embryos. In humans, skipping breakfast depresses glucose levels and so may be interpreted by the body as indicating poor environmental conditions and low food availability.

If you\’re going to raise a scrawny son because of the shortage of resources, said son is unlikely to breed, a scrawny daughter is more likely to breed than a scrawny son.

No, I\’m not a scientist, most certainly not a biologist, but I would assume that the sex selection takes place at implanation or not of the blasotocyst (if that\’s the correct word?).



The Dream of Every Scientist

“Our result show that one of the main assumptions of current models and theories is, in fact, quite wrong."

It doesn\’t matter what the subject is (in this case it\’s how starlings flock, but it could be about meiosis, hormesis or haplotypes) that\’s the one phrase that every scientist wants to be able to stand up in public and say. Preferably with proof of course.

It\’s also, to a large extent, why this science stuff works. People are endlessly trying to disprove the assumptions of others, not to find reasons why they are right, but to find out why they are wrong. What survives this process tends to be robust.

That\’s Nice

For some at least.

The Pentagon is spending billions of dollars on new forms of space warfare to counter the growing risk of missile attack from rogue states and the "satellite killer" capabilities of China.

Congress has allocated funds to develop futuristic weapons and intelligence systems that operate beyond the Earth\’s atmosphere as America looks past Iraq and Afghanistan to the wars of the future.

There will be those who gorge on the contracts sent out on an emergency basis.

The most ambitious project in a new $459 billion (£221.5 billion) defence spending Bill is the Falcon, a reusable "hypersonic vehicle" that could fly at six times the speed of sound and deliver 12,000lb of bombs anywhere in the world within minutes.

Unfortunately we\’ve already been involved in that one and I don\’t think we passed the required standards. Hafnium carbide is a) the most refractory (ie, highest melting point known) material and b) bloody hard to make.

This though looks much more interesting:

Darpa is also developing a small unmanned launch vehicle that would provide "responsive and affordable" access to space, for less than $5 million per launch. The first test flight was made in March.

Getting into orbit for that sort of price is an order of magnitude improvement. Only one more order of magnitude needed and we\’ll be "there". "There" being just about anywhere, for as has been pointed out, once you\’re in orbit, you\’re not half way to the Moon, you\’re half way to anywhere.

Racial Differences

This is a very odd statement for a scientist, a geneticist, to make:

Despite his frantic backtracking, James Watson\’s statement that Africans are less intelligent than Europeans follows a long and dubious tradition of geneticists claiming that supposed racial differences have a genetic basis.

If racial differences do not have a genetic basis then it\’s very difficult to think what they might be based upon. Things like the preponderance of red hair in Scotland, of long distance runners in East Africa, sprinters in West, epicanthic folds in Asia: these are clearly genetic markers of what we call race.

We can argue that race isn\’t an important idea, that our common humanity (and indeed, the fact that variability within groups is almost always larger than that between group averages) means we should disregard it.

We can also argue that while some things are indeed racial differences and have a genetic basis, that the things that people think are (to be crude, dick size, or to be less so, sexual appetite, or in this case, intelligence) are in fact not.

But to claim that none of the observable differences between different groups of humans have a genetic basis is simply absurd.

BTW, on what Watson actually said, that "Africans" or "blacks" have certain genetic traits that make them less intelligent than other groups. Others have pointed out that even the measurement of intelligence, let alone its inheritability, is still somewhat controvesial…..but to me the claim fails for a very different reason.

Let us assume many of his points: that there are groupings of humans that correlate with what we think of as races, That there is some genetic determination, some traits of these groups that are inheritable. If we do assume all of that then we do not get to a situation where we can talk about "Africans". For, at least as I understand it, there is more genetic variation in Africa than there is in the rest of the world.

The Zulu, the Pygmy, the Khoi San, the Ibo, Amhara, Dinka, (add groups to taste) show more variation between them than is found in the rest of humanity put together. Thus to state that "Africans" are genetically this or that is simply nonsense.