The Biology and Diversity of Extant Reptiles
The word reptile itself does not describe a monophyletic group of
vertebrates, like the mammals or birds. It is used to classify a
polyphyletic group of animals that are a subset of the larger group of
Amniotes. The term is best described through a cladogram: [IMAGE]
The reptiles first appeared in the early Carboniferous, having evolved
from labyrinthodont amphibians. They had several distinct advantages
over the amphibians that allowed them to flourish during the cold, dry
Permian period. These lead them to be the most successful group of
vertebrates and this period was referred to as the "age of reptiles."
They exploited all terrestrial niches, a few marine and even one group
took to the air. No other group of vertebrates had ever displayed such
diversity and mammals today are their only match. They were the first
group of tetrapods to successfully overcome the major problems of
terrestrial life, namely desiccation, thermoregulation and
respiration.
Adaptations to withstand desiccation
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Unlike amphibians reptiles are able to tolerate dryer conditions and
avoid desiccation. This allowed them to exploit more niches and
therefore achieve greater radiation. They did this in a number of
ways: 1 Skin. Reptilian skin is impermeable to water due to its unique
structure. It has a thick dermis and a thick epidermis. The relative
thickness of these layers helps somewhat in water conservation but it
is the components of the epidermis that make the skin waterproof. See
diagram: The α-keratin makes up the lower layer and is softer and more
pli...
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...whilst it is on land, something like a suspension bridge. Unlike the
chelonia, crocodiles do show a great deal of parental care, they build
and guard nests, help their young to hatch and acre for their young in
nursery pools for several weeks after hatching.Summary
As seen from this essay the diversity and subsequent biology of
reptiles is very wide and encompasses many niches. However reptiles
today are nowhere near as prolific as they were in the Mesozoic era
where they ruled the earth and exploited hundreds, if not thousands,
more niches. The real diversity and biology of reptiles was seen about
60 million years ago, before the mammals got a hold. But the only way
to investigate that is through the fossil record and that will never
give us all the information needed to draw a complete picture of
reptile diversity.
...ightly to allow some air to pass underneath it. Snakes can regulate their temperature by placing different proportions of their bodies in sun or in shade. The variations are numerous, but the end result is the same ¡V some degree of temperature regulation in reptiles.
Jurassic Park is the story of how one man’s idea puts many lives in danger. With lots of experimentation, scientists who worked for him were able to extract blood from prehistoric mosquitoes and other biting insects caught in amber then examine it for foreign blood cells. After that, they would extract them. Doing that, they could obtain DNA of extinct animals; dinosaurs who have been extinct for millions of years. Through a long process, they could recreate dinosaurs. Jurassic Park is a book full of suspense and horrifying murders. I wouldn’t recommend this book to everyone, but just people who enjoy science fiction and suspense. I also recommend not read Dennis Nedry’s death multiple times because it’s gross and...just gross. But other than that, I would give this five dinosaurs out of five dinosaurs!
“The skin of amphibians is water permeable, well supplied with glands, and often colorful, with the colors and patterns of many salamanders and anurans rivaling those of brightly colored birds. It performs many functions. It protects against abrasion and pathogens, serves as a respiratory membrane, perhaps marginally so in caecilians, absorbs and releases water, provides some dry-land species during droughts with a water-loss-resistant cocoon, and through color change (in some species) a...
At a time, scientists believed all dinosaurs were cold-blooded. However, with a recent discovery of a dinosaur found with a fossilized heart in the northern part of South Dakota in 1993, many paleontologists are starting to think that there were some dinosaurs that were warm blooded.
Iguanas and Komodo Dragons? These creatures have a lot in common and they have many differences. This report will talk about the mysteries of these beautiful creatures. And cover topics such as, What they eat, What they have in common, And what physical features they possess.
Some lizards have the ability to change color. For example, Anoles, and Chameleons can change color. Anoles change color by their moods, surrounding, and to camouflage themselves from predators. Chameleons change color by their surroundings and also to camouflage themselves from predators. Some lizards can also lose their tails and grow back a new one. The reason for that is because they don’t have a vertebrae in their tails. All Squamata reptiles have toes with claws to climb up trees and grasp food so the food won’t get away.
Pterosaurs were not dinosaurs but were closely related, and existed for 150 million years beginning in the late Triassic period through the Jurassic and Cretaceous periods until eventually becoming extinct along with the rest of the earth’s population at what is now known as the KT boundary event. The KT boundary event was the mass extinction that occurred at some point in time between the Cretaceous (K) and the Tertiary (T). This is famous because it marks the end of the 160 million years of dinosaur life. The theory is that asteroid rock hit the earth and caused the mass extinction. 1
By now, you have read on the Keenan Trial Blog, Chris Carver’s and Michael Bristow’s Autopsy in a MVC case.
One question that has stumped many paleontologists for centuries is, “Are birds dinosaurs?” Paleontologists have argued back and forth trying to prove or disprove each side of the theory. So far, advocates have supported their side through the facts of similar bone structures, bone organization, and the idea that dinosaurs had feathers. A common reaction that some people might have about the question is that there is no connection between the two species. Their main reasoning for this conclusion is based on the belief that the two do not have any similar characteristics. I too believed that there was no correlation between the two animals. However, after extensive research, I have completely changed my mind. I believe that birds are dinosaurs because they have similar bone structures, and they both possess feathers.
The debate of whether dinosaurs were cold blooded or warm blooded has been ongoing since the beginning of the century. At the turn of the century scientists believed that dinosaurs had long limbs and were fairly slim, supporting the idea of a cold blooded reptile. Recently, however, the bone structure, number or predators to prey, and limb position have suggested a warm blooded species. In addition, the recent discovery of a fossilized dinosaur heart has supported the idea that dinosaurs were a warm blooded species. In this essay, I am going to give supporting evidence of dinosaurs being both warm and cold blooded. I will provide background information on the dinosaur that was discovered and what information it provides scientists.
When you think of an ecosystem, you might think of lush forests, or wide oceans, abundant with wildlife. However, the Saguaro desert is unique in its own way. Hidden amongst the 91,446 million acres of this hot, harsh, desert, are a world of organisms that thrive to survive. Located in Arizona, this park’s variety of plant and animal life surpass all other North American deserts. It is divided into two districts, named after the mountain ranges that surround the park; named the Tuscan and Rincon. The saguaro cacti are very important to this ecosystem. In fact, the ecosystem is named after this massive cactus that calls this place its home. One very important organism that lives in the Saguaro desert is the horned lizard.
Chameleons are reptiles that have been living on Earth for over 100 million years. Chameleon fossils date back to the Paleonzene period. Their fossils have been found in Africa, Europe and Asia. Over half of the species of the chameleons live in Madagascar (Raxworthy, 2004). Chameleons are in the Animal Kingdom and Chordata Phylum. They get their name from the Family they are grouped in called Chamaeleonidae. Chameleons are closely realted to iguanas and other lizards. Although they are similar, chameleons have unique features that distinguish them from other lizards. The most distinguishing feature of chameleons is their ability to change the color of their skin.
As urbanization continues to expand amphibian population are on a global decline. In many rural areas, the only wetland available for aquatic reproduction is artificial ponds. While some species are able to persist in such an environment the majority of amphibians are negatively affected. The introduction of non-native species along with habitat degradation affects the successful reproduction of these native amphibians. Therefore, an understanding of the relationship between these species and their habitat is essential for conservation. This research sets out to determine conservation priorities for pond breeding amphibians in the hopes of preserving their existing populations.
In the third instalment of Jurassic Park, was a real swing and miss when it came to knocking it out of the ball park. With no spectacular or miraculous happenings to make the film truly stand out. The only contending players worthy of keeping a look out for being the Velociraptor’s, who were the films saving grace and true MVP’s.
Reptiles are vertebrate, or backboned animals constituting the class Reptilia and are characterized by a combination of features, none of which alone could separate all reptiles from all other animals.The characteristics of reptiles are numerous, therefore can not be explained in great detail in this report. In no special order, the characteristics of reptiles are: cold-bloodedness; the presence of lungs; direct development, without larval forms as in amphibians; a dry skin with scales but not feathers or hair; an amniote egg; internal fertilization; a three or four-chambered heart; two aortic arches (blood vessels) carrying blood from the heart to the body, unlike mammals and birds that only have one; a metanephric kidney; twelve pairs of cranial nerves; and skeletal features such as limbs with usually five clawed fingers or toes, at least two spinal bones associated with the pelvis, a single ball-and-socket connection at the head-neck joint instead of two, as in advanced amphibians and mammals, and an incomplete or complete partition along the roof of the mouth, separating the food and air passageways so that breathing can continue while food is being chewed. These and other traditional defining characteristics of reptiles have been subjected to considerable modification in recent times. The extinct flying reptiles, called pterosaurs or pterodactyls, are now thought to have been warm-blooded and covered with hair. Also, the dinosaurs are also now considered by many authorities to have been warm-blooded. The earliest known bird, archaeopteryx, is now regarded by many to have been a small dinosaur, despite its covering of feathers The extinct ancestors of the mammals, the therapsids, or mammallike reptiles, are also believed to have been warm-blooded and haired.