Sweta
Zoology
December 2021
The conservation of amphibian populations will benefit from a better knowledge of the factors that influence their existence and abundance. In 75 small lakes in grassland and parkland regions of Minnesota, we calculated the relative abundance of larvae of two common amphibian species, Tiger Salamanders (Ambystoma tigrinutn), and ranid tadpoles (Northern Leopard Frog Lithobates pipiens and Wood Frog Lithobates sylvaticus). In order to examine the effects of dynamic factors like fish abundance and static (study period) variables like fish community type, depth, and nearby land cover, we used a two-step procedure in which we first modelled presence-absence with data from all lakes and then modelled abundance only in lakes where the amphibian taxa were present. Although they were different for the presence and abundance models, fish factors had the most impact. The presence of salamanders and tadpoles was negatively linked with the quantity of benthivorous fish, whereas the abundance of salamanders and tadpoles was best described by fish community type. The epidermis, dermis, and hypodermis are the three primary layers of the multilayered skin found on all vertebrates. Mucus secretion is the integument's primary function in aquatic vertebrates. Cornification started in amphibians, progressed in reptiles, and persisted in the epidermis of birds and mammals. The most conspicuous and useful structure of bird skin, the feather, originated during the Mesozoic era. Following the demise of the dinosaurs, birds proceeded to diversify, followed by the growth, expansion, and diversity of mammals. This gets us to the most complex skin structure of mammals, which includes varying glands, cells, physiological pathways, and the development of hair.
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© Airo Journals 2021
