Of fingers, toes and penises

Article Abstract:

Genetics research has established that the posterior Hox gene is vital to the formation of extremities in vertebrates. Total digit agenesis was observed in the absence of Hox gene function. The research indicates that digits and external genitalia are apical growth mechanisms connected phylogenetically, perhaps via genetic control development. Histological slide preparations are shown to illustrate the impact of lacking Hox gene in genetic expression.

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The quirks of jerks

Article Abstract:

Denny and colleagues have reported that a reduction in hydrodynamic force may not protect structures attaching organisms to the shore from possible damaging loads, if inertial force is high on reaching the end of its tether. Mathematical models show the effects of waves on the inertial force on the organism, and a dimensionless index, known as the 'jerk number' is proposed to predict when inertial forces are significant for a wave-swept organism.

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Asymmetric toes aid underwater swimming

Article Abstract:

Issues are presented concerning the benefits which the asymmetric lobing of the toes of the great crested grebe give the bird during swimming. The lift to drag ratio created by the asymmetric lobes is discussed.

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