Len Yabloko's List: Signaling

Social psychologists have long observed that humans have a reliable ability to “read” each other. Now evidence is growing that we accomplish this through social signaling, an ancient system of communication that depends on non-verbal communication rather than speech.

This would contradict the most widely held hypothesis, that psychoactive substances made by plants are primarily defense mechanisms against herbivory. Coruzzi argues that the primary function of these compounds in plants may be to regulate signal transduction and that their role as a plant defense against herbivory is a secondary function that evolved in some plant species under selective pressure.

Animal signaling theory has recently become popular among anthropologists as a way to study human communication.  One aspect of animal signaling theory, often known as costly signaling or handicap theory, has been used particularly  often. This article makes four points regarding these developments: (1) signaling theory is broader than   existing studies may make it seem; (2) costly signaling theory has roots in the social as well as the biological  sciences; (3) not all honest signals are costly and not all costs borne by signalers serve to ensure honesty;  and (4) hard-to-fake signals are favored when the interests of broad categories of signalers and   receivers conflict but the interests of individual signalers and receivers converge.

The signaling architecture of the visual system used in long wavelength trichromats (humans and other large terrestrial mammals) is shown in the following figure. This figure emphasizes the three distinct signaling paths found in vision (the P-, Q- and R-channels) as well as the unique correlation channel (labeled the G'-channel) found in only the highest primates (hominoidea) and used by the analytical mode of vision for reading and other functions requiring maximum acuity and perception of detail.