Evolution of the upturned palm

Tierney writes a brief article in the Aug. 28 NYTimes science section on thinking about ancient origins of the "can you spare me a dime" upturned palm, noting that the upturned palm is a submissive gesture:

...a “gestural byproduct” of the circuits in the brain and spinal cord that protected vertebrates hundreds of millions of years ago..Confronted with a threat, ancient lizards would instinctively bend their spine and limbs to press their bodies closer to the ground, protecting the neck and head and signaling submission to a larger animal. This crouch display is the opposite of the high-stand display, the aggressive posture of a stallion or a gorilla raising its chest and head to appear larger...The human remnant of the crouch display is a shrug of the shoulders, which lowers the head and rotates the forearms outwards so that the palms face up. Conversely, the high-stand display persists in humans as a rotation of the forearms and palms in the opposite direction, producing the domineering palm-down gesture used by a boss slapping the conference table or an orator commanding quiet from his audience.

The Emory University group (Franz de Waal et al.) have found that Chimps and Bonobos use the palm-up gesture in a much more flexible way (depending on the situation and group) that vocalizations and facial expression (more strongly tied to emotions). This leads to speculation that gestures may have served as the steppingstone for early hominid communication and, possibly, language.