Author: Lensyl Urbano

Epigenetics: How our Environment Affects what our Genes Do.

The middle-school introduction to genetics tends to start with Mendel‘s pea experiments and end with Punnet Squares. The focus is on dominant and recessive genes and what’s expressed given various combinations.

Identically Different: Why You Can Change Your Genes by Tim Spector.

However, the way genes behave are not quite that simple. Tim Spector’s new book, Identically Different, goes into the ways that people’s behavior and environment — the things they eat; the chemicals that surround them — affect the way their genes behave. Even identical twins can be profoundly different depending on things that happen in the womb.

Perhaps the most intriguingly argument is that the behavior of grandparents can affect their grandchildren. In the post World War II period in Britain food was scarce, and some people tended to episodes of starvation alternating with binge eating. Spector links this to an increase in the obesity of their grandkids.

The idea that your behavior can affect the expression of your kids’ genes is more akin to Lamark’s view of evolution than Darwin’s.

↬ The Dish ↬ BrianAppleyard,com.

DarwinTunes: Watching Music Evolve

Take randomly generated sound waves (using sine curves for example), mix them together to get beats, and then let people decide which ones sound best. Let the best ones mate — add in small mutations — and wait a few thousand generations for the sound patterns to evolve into music.

That’s what DarwinTunes does, and they let you participate in the artificial selection process (artificial as opposed to natural selection).

The details are included in their article: Evolution of music by public choice by MacCallum et al. (2012).

Meaningful Progress: The Ultimate Motivator

Motivation is key to learning. Amabile and Kramer (2011) explain that strong motivation has been an essential driver in scientific discovery and the business world as well. They assert that:


Of all the things that can boost emotions, motivation, and perceptions during a workday, the single most important is making progress in meaningful work . And the more frequently people experience that sense of progress, the more likely they are to be creatively productive in the long run [my italics].

— Amabile and Kramer, 2011: The Power of Small Wins in Harvard Business Review.

So for education, we need to design work so that students can be challenged (which makes it meaningful), yet be able to make good progress. It’s a delicate balance to get each student into their “flow zone“, where the work is neither too hard, nor too easy.

Challenge vs. skill, showing "flow" region. (Image and caption by Wikipedia User:Oliverbeatson).

The Best Color Scale? Not Rainbow

Image from Borland and Taylor (2007).

Even though rainbow color maps look pretty, Borland and Taylor (2007; pdf) argue that they’re rarely the best choice for showing data.

The rainbow color map confuses viewers through its lack of perceptual ordering, obscures data through its uncontrolled luminance variation, and actively misleads interpretation through the introduction of non-data-dependent gradients.

–Borland and Taylor (2007): Rainbow Color Map (Still) Considered Harmful in IEEE Computer Graphics and Applications.

They recommend the much more boring (but visually useful) greyscale and bi-colored schemes, for things like temperature maps and so on where the data is continuous.

A pretty, but not very informative, rainbow color scale.

Starting Algebra too Early?

There’s been a push for students to take algebra earlier and earlier, yet there are some serious pedagogic arguments that early algebra might not be a great idea for many, if not most, students. A fascinating paper by Clotfelter et al., (2012) (pdf) showed pretty clearly that for a large number of students, taking algebra earlier actually resulted in worse performance in not just algebra, but the follow-up classes as well (geometry and pre-calculus for example), compared to students who waited to take the subject. Indeed the Charlotte-Mecklenburg School District (the district studied in the article) actually reversed their policy of having students take algebra in 8th grade.

Students affected by the acceleration initiative scored significantly lower on end-of-course tests in Algebra I, and were either no more likely or significantly less likely to pass standard follow-up courses, Geometry and Algebra II

— Clotfelter et al., (2012): The Aftermath of Accelerating Algebra: Evidence from a District Policy Initiative (pdf) via NY Fed.

The argument for early algebra comes from the correlation between early algebra and better performance on standardized tests, and more advanced math classes in high school. But the authors here indicate that forcing students to take algebra early does not result in the same outcomes.

The argument against early algebra is based on the research that shows formal thinking develops during adolescence, and the belief that to do well in algebra requires the abstract thinking skills that are seated in the maturing prefrontal cortex. Until students are ready for the abstract thinking required (which happens at different times for each student), they will struggle with algebra.

Algebra provides an essential foundation for further mathematics, which is why it is my strong preference that students progress by demonstrating mastery of the topics at their own pace rather than struggling through the class.

Letter Spacing and Readability (particularly for dyslexia)

Letter spacing. Read this.

Two European researchers have demonstrated that increasing the spacing between letters help students with dyslexia read faster, bumping up their reading ability by about a year. Their app for testing your best reading spacing, DYS, is free.

Robert Lee Hotz has the details.

Unlike having to use expensive fonts, like dyslexie, letter spacing is very easy to change on a webpage, and anyone should be able to change the preferences on their browser; for Mozilla Firefox you can change the letter-spacing using User CSS (which is not quite as easy as changing it in the preferences).

ᔥ Hotz, 2012.