Finches are the most popularly kept passerine species within aviculture. The zoonotic diseases of Fringillidae have always been a major concern for owners. Various viral, bacterial, fungal, parasitic and allergenic agents of Aves are able to transmit to humans. In the opening chapter of this compilatio, emphasis will be placed on the significance of each of the mentioned agents for public health. Specific subjects such as the epidemiology, economic significance, public health significance, transmission, clinical signs, diagnostic procedures and principle of disease prevention are examined, thus making owners aware of the serious threat of finches.Next, the authors discuss the way in which various information from the environment exerts strong selective pressure on the sensory systems of the organism, leading the organism through distinct paths in the adaptive evolutionary process. The visual system is responsible for capturing and processing light information. This system has developed in different ways during the evolutionary history of vertebrates, based on specific demands of the species. A review of these characteristics of the visual system of snakes will be addressed and discussed.In one study, the authors aim to fill the gap in knowledge regarding the nesting habits and specific biology of Melipona colimana, a stingless bee endemic to pine-oak tree forests in western Mexico. Nesting in these trees may be detrimental to the bees because this tree species is commonly used by humans to produce oak charcoal, a practice that destroys nesting sites.In the following chapter, the authors go on to introduce different types of ant nests with multiple queens, and providing examples of two species (Polyrhachis moesta and Camponotus yamaokai) with polygynous nests. The authors discuss how and why the number of queens varies, proposing that the plasticity of the number of queens is a strategy for successful colony founding, colony growth, and colony survival in ants.The identity of the elements of the hyobranchial skeleton in snakes is a controversy that has not been addressed recently. The single set of paired elements has been considered to be ceratohyals or extensions of the hypohyal, first ceratobranchials and second ceratobranchials in both the same and different groups of snakes. The morphology of this region in snakes is re-evaluated in terms of muscle anatomy, focusing on booid and colubroid snakes. The implications of the spatial separation of the tongue and the larynx from the hyobranchial skeleton are also discussed.The relationship between obesity/hypercholesterolemia and the decrease in male fertility has been reported clinically and in experimental models. The effect of high cholesterol intake and its impact in different tissue/organs has also been described in several animals models. But few documents focus on the addition of natural products to food as a protective diet, in order to avoid sperm alterations. In the final chapter, New Zealand male rabbits fed with a high-fat diet were associated with deleterious changes in semen and sperm cells. The reported alterations include: decreased semen volume and sperm count and an increase in abnormal sperm morphology.