61–80 of 816
This precocity of childhood may be said to characterise all the known races of man, and to be even more marked the more primitive the race. On this point, ‘It is an interesting fact,’ says Havelock Ellis (183, p. 177), ‘and perhaps of some significance, that among primitive races in all parts of the world, the…
Hartmann, in his work on the Anthropoid Apes (289, p. 301), quotes, approvingly, the words of Vogt: ‘When we consider the principles of the modern theory of evolution, as it is applied to the history of development, we are met by the important fact that in every respect the young ape stands nearer to the human child…
The Real Significance of Play.—This scheme is, doubtless, imperfect, as critics of Groos’s book have taken occasion to point out, but the idea which underlies it all is a most suggestive and illuminating one, when rightly understood. In his latest work on the play of man, which has recently appeared, Groos makes clear…
hough it’s not easy to pinpoint the causes of the rise in IQ scores, it’s no paradox that a heritable trait can be boosted by changes in the environment. That’s what happened with height, a trait that also is highly heritable and has increased over the decades, and for some of the same reasons: better nutrition and…
When I was a boy, a popular literary genre for children was the heroic biography of a medical pioneer such as Edward Jenner, Louis Pasteur, Joseph Lister, Frederick Banting, Charles Best, William Osler, or Alexander Fleming. On April 12, 1955, a team of scientists announced that Jonas Salk’s vaccine against polio—the…
At the time when the lines begin, in the mid-18th century, life expectancy in Europe and the Americas was around 35, where it had been parked for the 225 previous years for which we have data.3 Life expectancy for the world as a whole was 29. These numbers are in the range of expected life spans for most of human…
The current push to bring digital games into school is, strictly speaking, not the first, nor even the second time that educators have pushed for individualized instruction via machines. But it is decidedly the most nuanced, humanistic, and thoughtful. The first actually took place in the 1950s and early 1960s, when a…
From a female perspective, pregnancy is always a huge investment. Even more so if her species has a hemochorial placenta. Once that placenta is in place, she not only loses full control of her own hormones, she also risks hemorrhage when it comes out. So it makes sense that females want to screen embryos very, very…
Inside the uterus we have a thick layer of endometrial tissue, which contains only tiny blood vessels. The endometrium seals off our main blood supply from the newly implanted embryo. The growing placenta literally burrows through this layer, rips into arterial walls and re-wires them to channel blood straight to the…
If you give people a tool and tell them it will perfectly solve an important problem, any imperfection in the tool is going to make them angry. If you give someone a toy and say “Look what I made! Isn’t it fun? It kinda does this thing.” then you’ve set yourself up for a positive reaction. It’s much easier to beat low…
To answer the simplest question of whether taking in more protein during weight training led to larger increases in muscle size and strength, the researchers added all of the results together. [...] But those who did ramp up their protein gained an extra 10 percent or so in strength and about 25 percent in muscle mass…
RESULTS: Without adjustment, meta-analysis of all 87 included studies replicated the classic J-shaped curve, with low-volume drinkers (1.3-24.9 g ethanol per day) having reduced mortality risk (RR = 0.86, 95% CI [0.83, 0.90]). Occasional drinkers (<1.3 g per day) had similar mortality risk (RR = 0.84, 95% CI [0.79…
It is widely accepted that aging is accompanied by remodelling of the immune system including thymic atrophy and increased frequency of senescent T cells, leading to immune compromise. However, physical activity, which influences immunity but declines dramatically with age, is not considered in this literature. We…
The observation that play gets short shrift as children come of age in the Western world is surely as old and as perennial as that civilization itself. The Bible puts it thus: "When I was a child, I spake as a child, I felt as a child, I thought as a child: now that 1 am become a man, I have put away childish things."…
When genes are activated, the instructions encoded within their DNA are first transcribed into a related molecule called RNA. Shepherd’s colleague Elissa Pastuzyn showed that the Arc shells can enclose RNA and move it from one neuron to another. And that’s basically what retroviruses do—they use protein shells to…
In an experiment at Cornell, stressed college students randomly assigned to scroll through their own Facebook profiles for five minutes experienced boosts in self-affirmation compared to students who looked at a stranger’s Facebook profile. The researchers believe self-affirmation comes from reminiscing on past…
Americans enjoy lower qualities of life on every single indicator that you can possibly think of. Life expectancy in France and Spain is 83 years, but in America it’s only 78 years — that’s half a decade of life, folks. The same is true for things like maternal mortality, stress, work and leisure, press freedom…
Beginning in middle age and continuing through later adulthood, individuals are often motivated by events in their own lives or the lives of significant others to obtain health-related information.^^ Health-related concerns draw many adults into a new domain of science learning. At the same time, with retirement…
What madness may have to do with creativity and genius has continued to intrigue down to this day, with scholars arguing for and against the association, its benefits and its deficits. In 1995, in a large scale and statistically convincing study of 1,004 eminent individuals of the 20th century, psychiatrist Arnold…
gonzoflip 1 hour ago | unvote [-] I have family that farms in Iowa and I also worked in the agriculture industry there for a while after leaving the military. One thing that increases the stress on the farmers is the way they avoid income taxes at all costs so they rarely save any of the profits from good years to…