Book-carrying positions – typically “male” or typically “female” – a re-examination

August 16th, 2018

1976 was something of a pivotal year for research aimed at establishing whether men and women tend to carry books in different ways – with no less than 3 key papers appearing in the literature [see references below]. Some seventeen years later however, the subject was re-examined – by Evelyne Thommen, Emiel Reith, and Christiane Steffen at the University of Geneva, who, as a result of a 6-year long study, questioned, or perhaps even challenged, the view that it’s valid to define the various carrying positions as either typically “male” or typically “female.”

“The present authors conducted five observational studies on carrying behavior in Geneva, Switzerland, over a 6-yr. period. In each sample, almost 50% of women adopted the same positions as men. These results show that it is necessary to question the gender-stereotypical nature of book-carrying positions and to consider gender differences in behavior from a more dynamic standpoint.”

See: Gender-Related Book-Carrying Behavior: A Reexamination in Perception and Motor Skills, Volume: 76 issue: 2, page(s): 355-362 (1993). A full copy may be found here.

1976 references :
Carrying Behavior in Humans: Analysis of Sex Differences, Donald A. Jenni and Mary A. Jenni Source: Science, New Series, Vol. 194, No. 4267 (Nov. 19, 1976), pp. 859-86

The development of sexually dimorphic book carrying behavior Hanaway, T.P. & Burghardt, G.M. Bulletin of the Psychonomic Society (1976) 7: 267.

The effects of sex. book weight and grip strength on book-carrying styles Philip J. Spottswood & Gordon M. Burghardt, Bulletin of the Psychonomic Society 8 (2):150-152 (1976)

Is He on the Level? The Master of Complexity.

August 15th, 2018

“Is he on the level?” and “What level?” are two questions you might ask after learning about Dr. Michael Lamport Commons and the 16 levels he invented. The 16 levels are parts and parcels in Dr. Michael Lamport Commons’s “Model of Hierarchical Complexity.” The model rates how complex a person (or a bacterium) is, compared to all other persons (or bacteria).

Who is Dr. Michael Lamport Commons [pictured here]? He is a “Corresponding Member of the Faculty of Psychiatry Institution, Beth Israel Deaconess Medical Center,” according to the Harvard web site. He is an “Assistant Clinical Professor,” according to Dr. Michael Lamport Commons’s web site.

He is many things. He is director of the Dare Association, a place of complexity that subspecializes in undue influence.

He is a fixture in many scholarly journals that you may not have heard of. According to Dr. Michael Lamport Commons’s Wikipedia page, which boasts a warning about veracity:

He is on the governing board of the Journal of Behavior Analysis Online. He is co-editor of the journal Behavioral Development Bulletin and past co-editor of the Journal of Behavior Analysis Online. He was a senior editor of Quantitative Analyses of Behavior, Volumes 1–11 and of four volumes on Adult Development including Beyond Formal Operations: Late Adolescent and Adult Cognitive Development and Clinical Approaches to Adult Development, as well as associate editor for a special issue of Journal of the Experimental Analysis of Behavior on the nature of reinforcement. He is the consulting editor of Moral Development Series.

What is the Model of Hierarchical Complexity? Dr. Michael Lamport Commons explains:

Model of Hierarchical Complexity (MHC)… is a measurement theory that analyzes the developmental difficulty of tasks represented by the Orders of Hierarchical Complexity. It represents the behavioral developmental stages at which an individual is performing while completing a task.

The MHC has 16 levels, Dr. Michael Lamport Commons explains:

It organizes behaviors into orders of complexity ranging from 0-16. The lowest order, order 1, corresponds to automatic responses to a single stimulus, such as taxes in bacteria. Each order above this is composed of two or more lower order behaviors organized into a new structure.

In this exciting action video, Dr. Michael Lamport Commons explains—in a way someone can understand, in theory—his Model of Hierarchical Complexity:

What about Dr. Michael Lamport Commons himself? What level is he on? Could there be a 17th level? These are all questions.

Physics Breakthough: Snapping a Spaghetti Strand Into 2 (Not 3!) Pieces

August 13th, 2018


Spaghetti—dry spaghetti—again feeds the intellectual fervor of physicists. Five physicists serve up a surprising new study about an old question about bending a strand past its breaking point:

Controlling Fracture Cascades Through Twisting and Quenching,” Ronald H. Heisser, Vishal P. Patil, Norbert Stoop, Emmanuel Villermaux, and Jörn Dunkel, Proceedings of the National Academy of Sciences, 2018.

The authors, at Cornell University, the Massachusetts Institute of Technology, Université Aix Marseille, and the  eCNRS/MIT/AMU Joint Laboratory, build upon an Ig Nobel Physics Prize-winning study [“Fragmentation of Rods by Cascading Cracks: Why Spaghetti Does Not Break in Half,” Basile Audoly and Sebastien Neukirch, Physical Review Letters, vol. 95, no. 9, August 26, 2005, pp. 95505-1 to 95505-1].

Heisser and colleagues describe how—by twisting, as well as bending—they induce a strand of dried spaghetti to break into only two (not more than two!) pieces:

A well-known problem with direct implications for the fracture behavior of elongated brittle objects, such as vaulting poles or long fibers, goes back to the famous physicist Richard Feynman who observed that dry spaghetti almost always breaks into three or more pieces when exposed to large bending stresses. While bending-induced fracture is fairly well understood nowadays, much less is known about the effects of twist. Our experimental and theoretical results demonstrate that twisting enables remarkable fracture control by using the different propagation speeds of twist and bending waves.

(Thanks to Dan Cohen for bringing this to our attention.)

BONUS: provides a few additional details, and a photograph of spaghetti.

BONUS: Here’s video of other people’s earlier, mostly unsuccessful attempts—before the twist breakthrough occurred:

BONUS (unrelated): A monograph, by someone else, called “Heisenberg uncertainty principle and the strange physics of spaghetti” meanders into rather different aspects of dry spaghetti. The monograph has an accompanying one-hour-and-22-minutes-long video, which you might enjoy if you enjoy one-hour-and-22-minutes-long videos that meander into rather different aspects of dry spaghetti:


One month from today: the 28th First Annual Ig Nobel Prize Ceremony

August 13th, 2018

The 28th First Annual Ig Nobel Prize ceremony happens on Thursday evening, September 13, in Sanders Theatre, Harvard University.

Ten new winners will be awarded Ig Nobel Prizes, for achievements that make people LAUGH, then THINK. The ceremony will include the premiere of “The Broken Heart Opera.”

A few tickets to the ceremony are still available. The event will be webcast live.

Details are on the ceremony web page.

Hydroplaning Eider Ducks – the math(s)

August 13th, 2018

Ducks can fly. Ducks can swim. And, unusually, they’re pretty good at something in between – viz. hydroplaning (a.k.a. ‘Skeetering’). If you’ve seen them doing it, you might have wondered about the physics (and math(s)) behind it. In which case, you are not alone …

“Common eiders (Somateria mollissima) are heavy sea-ducks that spend a large portion of their time swimming at the water surface. Surface swimming generates a bow and hull wave that can constructively interfere and produce wave drag. The speed at which the wavelengths of these waves equal the waterline length of the swimming animal is the hull speed. To increase surface swimming speed beyond the hull speed, an animal must overtake the bow wave. This study found two distinct behaviors that eider ducks used to exceed the hull speed: (1) “steaming,” which involved rapid oaring with the wings to propel the duck along the surface of the water, and (2) “paddle-assisted flying,” during which the ducks lifted their bodies out of the water and used their hind feet to paddle against the surface while flapping their wings in the air.”

A mathematical formula which goes some way in describing the phenomena is proposed by the research team behind the paper : Aquatic Burst Locomotion by Hydroplaning and Paddling in Common Eiders (Somateria mollissima) Journal of Experimental Biology, 218: 1632-1638.