Topic: Biology
Fascinating piece in today's NY Times about Autism and Testosterone by the researcher Simon Baron-Cohen.
From the article:
On average, males finish faster and score higher than females on a test that requires the taker to visualize an object's appearance after it is rotated in three dimensions. The same is true for map-reading tests, and for embedded-figures tests, which ask subjects to find a component shape hidden within a larger design. Males are over-represented in the top percentiles on college-level math tests and tend to score higher on mechanics tests than females do. Females, on the other hand, average higher scores than males on tests of emotion recognition, social sensitivity and language ability.
Many of these sex differences are seen in adults, which might lead to the conclusion that all they reflect are differences in socialization and experience. But some differences are also seen extremely early in development, which may suggest that biology also plays a role. For example, girls tend to talk earlier than boys, and in the second year of life their vocabularies grow at a faster rate. One-year-old girls also make more eye contact than boys of their age.
In my work I have summarized these differences by saying that males on average have a stronger drive to systemize, and females to empathize. Systemizing involves identifying the laws that govern how a system works. Once you know the laws, you can control the system or predict its behavior. Empathizing, on the other hand, involves recognizing what another person may be feeling or thinking, and responding to those feelings with an appropriate emotion of one's own.
His research has found that men tend to be systhemizers (type S) and women empoathizers (type E). He points out some studies that suggest that exposure of prenatal infants to testosterone in amnionic fluid influences their ability to display S-type and E-type behaviors. Testosterone exposure levels correlates with S-type behavior and inversely correlates with E-type behavior. Hmm, is Larry reading this? Although I warn you all not to make simplistic judgements based on these studies.
What does all this have to do with autism? According to what I have called the "extreme male brain" theory of autism, people with autism simply match an extreme of the male profile, with a particularly intense drive to systemize and an unusually low drive to empathize. When adults with Asperger's syndrome (a subgroup on the autistic spectrum) took the same questionnaires we gave to non-autistic adults, they exhibited extreme Type S brains. Psychological tests reveal a similar pattern.
Very interesting! Instead of a little Einsteins, testosterone exposure can produce a Rain Man.
FIRST, both mothers and fathers of children with autism complete the embedded figures test faster than men and women in the general population.
Second, both mothers and fathers of children with autism are more likely to have fathers who are talented systemizers (engineers, for example).
Third, when we look at brain activity with magnetic resonance imaging, males and females on average show different patterns while performing empathizing or systemizing tasks. But both mothers and fathers of children with autism show strong male patterns of brain activity.
Fourth, both mothers and fathers of children with autism score above average on a questionnaire that measures how many autistic traits an individual has. These results suggest a genetic cause of autism, with both parents contributing genes that ultimately relate to a similar kind of mind: one with an affinity for thinking systematically.
returned to Portugal. We spent time in Lisboa, Setubal and now we just finished our Marathon Port tasting tour ... tonight we see the musical Amalia about the queen of
Here are my travel companions in the Plaza de la Corredera in the center of Cordoba's old city. Later we visited la Mezquita (see pics below), it was first a Visigothic Cathedral that was destroyed by the Moors, then a giant Mosque (3rd biggest in the world). Where Cordoba was reconquered by the Christians in the 1200s, a giant Cathedral (see pic #4) was built in the center of the Mosque.

Last week I picked up Elaine Morgan's
Well I was taking some phase pictures of hepatocytes (liver cells) that we plated on a collagen coated coverslip - nice cells, if I do say so myself. To the left is an image of a hepathocyte (or part of a hepathocyte), all those lines and squiggles being organelles ... compartments where specialized cellular functions take place.
(Well maybe they just glide.)
Last night we finally watched the last two episodes of
In today's issue of Cell,
Among Osama bin Laden's greatest supporters are the poor. But if one examines those that flew into the planes into the towers, most were educated in the west, and they were middle class, not poor. As for the US international relations, it's true that the US government has had cozy relations with most of their tyrannical dictators, mainly due to our need for oil. It's also true that our biased siding with the hardliners in Israel has not helped us ... but I think that we suffer from not interacting enough (economically) with the Middle-east. If you look at the world map, all the parts of the world that produce terrorists are the parts of the world that are not taking part in global trade. Besides terrorists, all that those countries export is oil. They are not educating or preparing their citizens for international trade. Economic prosperity and the increase in education that comes along with trade produces a middle class, which in turn drives for political moderation and a stomping out of irrational, religious extremism. These ideas are discussed greatly in a fantastic book by
OK ... lets step back a bit. In 1972, a model of how lipids form a membrane was proposed by Singer and Nicolson ... the fluid mosaic model. The famous cartoon from their paper is seen here (right). In this model, biological membranes were composed of two layers (or a bilayer) of lipids. The membrane is stable as the lipid's hydrophilic (water loving) heads (circles in the pic on the right) are exposed to the solution and their hydrophobic (water fearing) acyl side chain (squiggles in the pic on the right) are buried in the membrane core. Membrane bound proteins (big blobs in the pic) would float in the plane of the membrane.
but despite this fact, Schutz et al. saw them by labeling single lipids and adding just the right amount of these labeled molecules to muscle cells. Others have observed that in polarized cells
So remember the
goes along the lines of "one degree, that's nothing!", but it's not how much the environment changes but how fast. If the change is too rapid, species can't evolve to adapt to the change, leading to a collapse of the deck of cards. In other words if the change happens over generations, it give the gene pools time to adapt - but if the genetic complement of a species can't catch up with the change, then whole species are left in the lurch and that's when a whole ecosystem can collapse.
As for hydroelectric energy, well there are only so many dams you can build. Solar and Wind energy? It's viable for small communities like the Boston harbor island (right) but the amount of space these take up is tremendous. 