An enzyme generally catalyzes one well defined reaction with high specificity and efficiency. We report here in contrast that the copper protein hemocyanin of the tarantula Eurypelma californicum exhibits two different functions. These occur at the same active site. While hemocyanin usually is an oxygen carrier, its function can be transformed totally to monophenoloxidase and o-diphenoloxidase ...

The limb movements of many multilegged animals occur in metachronal sequences, often sequences running from posterior to anterior. Such sequences are not so conspicuous in animals with few legs. However, for the walking of certain insects with variable gaits it has been possible to produce a descriptive model based on metachronal rhythms with stepping pattern varying with frequency (Wilson, 196...

An otherwise healthy three-year-old boy was referred to the emergency department with a one-day history of redness, pain and sensation of foreign bodies in his left eye. His parents had held a birthday party the day before, during which he was in contact with exotic animals, including a tarantula. No other children at the party were symptomatic. Treatment with erythromycin ointment four times d...

Previous studies in the wolf spider Lycosa tarantula (Linnaeus 1758) have shown that homing is carried out by path integration and that, in the absence of information relative to the sun's position or any pattern of polarized light, L. tarantula obtains information as to the angle it must turn to home through the anterior lateral eyes (ALEs). In the present study, spiders were trained to walk o...

New data on the tarantula genus Chaetopelma Ausserer, 1871 are provided. A new species, Ch. persianum sp. nov. , is described based a single female specimen collected in northwestern Iran, which represents easternmost record of within its entire known range. Additionally, correct publication date olivaceum C.L. Koch, 1842 discussed, and distribution records all species mapped.

A new record of the tarantula genus Phlogiellus Pocock, 1897 from Thailand is described. Distributional data, natural history, morphological characters, and illustrations of male and female are provided. The Thai specimens belong to a new species, Phlogiellus longipalpussp. n. The diagnosis of the new species and related species are discussed.

Muscle contraction involves the interaction of the myosin heads of the thick filaments with actin subunits of the thin filaments. Relaxation occurs when this interaction is blocked by molecular switches on these filaments. In many muscles, myosin-linked regulation involves phosphorylation of the myosin regulatory light chains (RLCs). Electron microscopy of vertebrate smooth muscle myosin molecu...