Reptiles and Amphibians
There are many different kinds of reptiles, including snakes, turtles, and lizards. Each of them has unique features that make them fascinating to watch. These features include their skull morphology, Reproductive organs, and placenta. Adaptation is another important trait, as is the ability to reproduce.
Reptiles and amphibians have evolved a variety of adaptations to thrive in climates that are extremely hot and dry. Reptiles have a thick scaly skin that prevents water loss and protects against skin damage. Reptiles also have a highly efficient excretory system that excretes urine that is highly concentrated. Their eggs also have a hard calcium shell and leathery coating.
Because most reptiles do not generate internal heat, adaptations that regulate body temperature are essential. This thermoregulation is achieved through the complex interaction of body temperature, physiological processes, and behavior. Some reptiles are nocturnal and passively exchange heat with the air and soil. Others are active during the day and rely on a natural light source for heat.
The book Skull Morphology of Reptiles presents the skull morphology of reptiles. It is a monumental work in the field of reptile biology, serving as the authoritative reference for generations of herpetologists. This volume includes a detailed discussion of the skull morphology of snakes and lizards and is the first book of its kind to address the subject in such a comprehensive way.
Skull morphology of reptile species has remained relatively unchanged through time, but there are some distinct features of reptile skull morphology that differ from one another. In general, snakes have a more rounded skull compared to lizards.
The placenta of reptiles differs from the placenta of mammals in several ways. Reptile placentas are characterized by a trilaminar arrangement of the extraembryonic membrane. In reptiles, the yolk sac contributes to maternal-fetal exchange and regulates nourishment of the embryo. This type of placentation is found in most major taxa of viviparous amniotes. It contributes to the formation of three different types of placentas: choriovitelline placenta, omphaloplacenta, and omphaloplacenta.
Placentas are formed when a live-bearing reptile releases its eggs into an oviduct. The eggs develop into a baby before being born. The placenta does not provide much food to the embryo, as the eggshell remains in the nest and yolk provides nutrition.
Reptiles have several different reproductive organs. Primary reproductive organs include the ovaries and testes, which produce gametes and hormones that regulate reproductive physiology. Secondary reproductive organs include glands and structures that transport and nurture developing offspring. Reptiles also have reproductive organs that are not easily visible.
Male reptiles have a special reproductive organ, known as the oviduct, which is used for introduction of seminal fluid from the testes into the female genital tract. The seminal fluid protects sperm from drying out and helps them move freely. The oviduct is also where the embryo develops.
A major concern in reptiles’ ecology is climate change. Climate change has the potential to cause rapid changes in environmental temperatures, which affect reptiles’ reproductive success and survival. Various factors contribute to this effect, including increased temperature variability and altered rainfall regimes. Furthermore, the loss of habitats, invasive species, and disease may all cause a decline in population numbers and diversity.
The Physiological Ecology of Reptiles (PERL) lab at Cal Poly focuses on the study of the ecology and physiology of reptiles in their native habitat. The research involves free-ranging animals in their natural habitat and is primarily aimed at identifying environmental variables that can influence their behavior. While most of the study organisms are lizards and rattlesnakes, the lab also studies tropical snakes.
Reptiles need a balanced diet with a variety of vegetables, fruits, and other foods. A diet high in vitamins and minerals is especially important for herbivorous species. Herbivorous reptiles, such as snakes, are particularly susceptible to vitamin deficiency. Store-bought vegetables and fruits often have a poor calcium-to-phosphorus ratio, and their nutritional value is insufficient for reptiles. Large monitor lizards and snakes, on the other hand, eat whole vertebrates.
Reptiles can live for long periods without food or water, but they should be provided with several meals a day. They need three meals a day during hotter weather, but only two meals during colder seasons. If possible, feed them when they are active so they can get all the nutrients they need.
Reptiles have two main reproductive modes: viviparous and oviparous. They have also evolved distinct phylogeographic lineages. Although the origins of both reproductive modes are unknown, recent studies have shed new light on the processes involved in reptile reproduction. In some groups, like lizards, viviparity evolved as a response to a cooler climate.
The first step in diagnosis of reproductive diseases in reptiles is the physical examination. A physical examination and a blood test will help identify the presence of any abnormalities. A complete blood count and plasma biochemical analysis are also necessary to diagnose follicular stasis, which is the failure of mature follicles to ovulate. This condition is usually due to a variety of causes, ranging from incorrect husbandry to underlying disease.