When the map says race but all you can talk about is fatherhood

Family Inequality

Raj Chetty and colleagues have a new paper showing that « childhood environments play an important role in shaping gender gaps in adulthood. » Essentially, boys from poor or or single parents are doing worse. Also, this gender difference is greater in Black and poor places.

The tricky thing with this data, and I don’t blame Chetty et al. for this, although I would like them to say more about it, is that they don’t know the race of the children. The data are from tax records, which allow you to know the income and marital status of the parents, but not the race. But they know where they grew up. So if they have a strong effect of the racial composition of the county kids grow up in, but they don’t know the race of the kids, you have to figure a big part of that is race of the kids —…

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Why zebras have stripes (hint: it’s not for camouflage)

Why Evolution Is True

Africa harbors three living species of zebras: the plains zebra (Equus quagga), with several subspecies, the mountain zebra (Equus zebra), and Grévy’s zebra (Equus grevyi). The taxonomy of the group is in fact disputed, as distinct species sometimes produce fertile hybrids when they live in the same place, but let’s not worry about that now. The most distinctive feature these species have in common is, of course, their stripes: they are the only fully-striped members of the genus Equus (zebras, horses, and asses), a group containing eleven species. Here’s what the three zebras look like (notice the difference in pattern):

burchell Plains zebra

Hartmann_zebra_hobatere_S Mountain zebra

zebra_grevy_gallery Grévy’s zebra

Now why do they have stripes? If you’re asking the question as an evolutionary one, then one way to pose it is to ask, « What were the selective advantages to the ancestor of modern zebras of having the striped pattern? » (Stripes evolved…

Voir l’article original 1 433 mots de plus

When the map says race but all you can talk about is fatherhood

Family Inequality

Raj Chetty and colleagues have a new paper showing that « childhood environments play an important role in shaping gender gaps in adulthood. » Essentially, boys from poor or or single parents are doing worse. Also, this gender difference is greater in Black and poor places.

The tricky thing with this data, and I don’t blame Chetty et al. for this, although I would like them to say more about it, is that they don’t know the race of the children. The data are from tax records, which allow you to know the income and marital status of the parents, but not the race. But they know where they grew up. So if they have a strong effect of the racial composition of the county kids grow up in, but they don’t know the race of the kids, you have to figure a big part of that is race of the kids —…

Voir l’article original 465 mots de plus