In green iguanas, the pineal controls the circadian rhythm of body temperature but not the rhythm of locomotor activity. As part of a program to investigate the characteristics of this multioscillator circadian system, the authors studied the circadian rhythms of the electroretinographic response (ERG) and asked whether the pineal gland is necessary for the expression of this rhythm. ERGs from ...

Patterns of muscle activity during lung ventilation, patterns of innervation and some contractile properties were measured in the hypaxial muscles of green iguanas. Electromyography shows that only four hypaxial muscles are involved in breathing. Expiration is produced by two deep hypaxial muscles, the transversalis and the retrahentes costarum. Inspiration is produced by the external and inter...

A total of 38 ticks were collected on black spiny-tailed iguana, Ctenosaura similis, in a secondary dry forest from northern lowlands Guanacaste, Costa Rica. At the time finding, animal has not mobility hind legs and tail. Ticks identified morphological molecularly as Amblyomma scutatum. PCR amplification tests to Rickettsia, Anaplasmataceae Borrelia negative. Possible caused lack is discussed.

The generally accepted framework for the evolution of a key feature of the avian respiratory system, unidirectional airflow, is that it is an adaptation for efficiency of gas exchange and expanded aerobic capacities, and therefore it has historically been viewed as important to the ability of birds to fly and to maintain an endothermic metabolism. This pattern of flow has been presumed to arise...