Uses and misinterpretations of genetics in psychology

An analysis is made of the frequently posed question in psychology of relative contribution of genotypes and environments to phenotypic variation. The illogic of the question, the inappropriateness of the methodology, the inadequacy of the data, and the misleading implications of assertions of proportionality as seen through a sampling of introductory psychology textbooks and referenced publications are outlined. To ask the question of proportionality (of the relative contribution of genotypes and environments in human populations) requires the questioner to make two major erroneous assumptions. The first error is to grant validity to heritability estimates for humans. The second is to conceptualize the genotype as having a range of potential outcomes. An examination is made of these false assumptions. This revised version was published online in August 2006 with corrections to the Cover Date.     

Sensory surface of the saccule and lagena in the ears of ostariophysan fishes

The inner ears of a few fishes in the teleost superorder Ostariophysi are structurally unlike those of most other teleosts. Scanning electron microscopy was used to determine if other ostariophysans share these unusual features. Examined were the families Cyprinidae, Characidae, and Gymnotidae (all of the series Otophysi), and Chanidae (of the sister series Anotophysi), representing the four major ostariophysan lineages, the auditory organs of which have not yet been well described. Among the Otophysi, the saccular and lagenar otolith organs are similar to those reported for other ostariophysans. The lagena is generally the larger of the two organs. The saccular sensory epithelium (macula) contains long ciliary bundles on the sensory hair cells in the caudal region, and short bundles in the rostral region. The saccule and the lagena each have hair cells organized into two groups having opposing directional orientations. In contrast, Chanos, the anotophysan, has a saccular otolith larger than the lagenar otolith, and ciliary bundles that are more uniform in size over most of its saccular macula. Most strikingly, its saccular macula has hair cells organized into groups oriented in four directions instead of two, in a pattern very similar to that in many nonostariophysan teleosts. We suggest that the bi-directional pattern seen consistently in the Otophysi is a derived development related to particular auditory capabilities of these species.     

A re-examination of animal tropisms

The goldfish, Carassius auratus, was subjected to direct current stimulation in a long, narrow test-tank in an attempt to define and isolate the existence of galvanotropisms in vertebrates (forced, stimulus-bound uniform movements toward the cathode) as a behaviour distinct and separate from taxic (highly variable ‘escape’ or adaptive) movements. Contrary to previous research, subjects spent significantly more time in the cathode half of the tank than in the anode half. Both the velocity and behavioural characteristics of the movements toward the cathode drastically differed from the movements away from the cathode. Stimulus onset and offset responses were noted. The tropistic behaviour patterns evidenced in this research, as distinct from taxes, do not follow traditional conceptions of S-R relationships.     

Photosynthetic response of marine phytoplankton to eserine salicylate,a zooplankton anaesthetizing substance

Addition of eserine salicylate, a synaptic metabolic inhibitor, to marine algal cultures of Sketetonema costatum (Greville) Cleve, Dunaliella tertiolecta Butcher, and Prorocentrum micans Ehrenberg had a varied effect on the rate of respiration; α (the initial slope of the light saturation curve) and P^B_m (the saturation curve) and P (the specific production rate at optimal light intensity). As these effects were either concentration dependent, species specific or both, we find that it is not possible to manipulate photosynthesis-light relationships in a predictable manner by eserine salicylate treatment.     

Lipid-mediated motor-adaptor sequestration impairs axonal lysosome delivery leading to autophagic stress and dystrophy in Niemann-Pick type C

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