The cheetah, Acinonyx jubatus, is an animal that is well known for it’s speed. It’s characteristics are unique in comparison to other cats, like lions, leopards, and servals that inhabit the african continent. Each of the cats in Africa adapted to their own particular niches as environmental factors pushed them to different ecological climates than where their ancestors lived. This is part of the reason as to why the cheetah is remarkably different than other cats that live in Africa. Additionally, the cheetah is the only extant species in their genus, Acinonyx. It is hypothesized that there are at least 10 other, now extinct, species that belonged to the Acinonyx genus, which doesn’t include the 5 subspecies of the living cheetah.[1] The …show more content…
It includes two extant genera: Puma and Acinonyx and 3 extant species: the cheetah, the cougar, and the jaguarundi. It’s hypothesized that the cougar and jaguarundi likely got displaced during the Great American Interchange between Americas, but were likely of North American descent. This is in stark contrast to the cheetah whom likely originated from Eurasia in the late Pliocene-Pleistocene era and currently lives in African grasslands and semi desserts. Cheetah’s also inhabited Asia, but they were exterminated by humans there.[2] Recently, the first almost fully intact primitive cheetah skull was found in China. It has been dated back to ~2.2-2.5 million years ago, which makes sense in regards to when the puma clade diverged.[2] In regards to the skull, it is important to note that the cheetah that is known today, is genetically different than the American cheetah, Mircacinonyx, that existed during the Pilo-Pleistocene time period in the Americas. The skull that was found is likely to be a primitive ancestor to the extant cheetah based on cladistic …show more content…
Cheetah premolar teeth are distinct from other cat species because they are more slender and blade-like, yet the found skull seems to have premolars that are more morphologically similar to other felids. This suggests that this primitive cheetah skull is the crown of the evolutionary cascade to create the extant cheetah and it’s more recent ancestors. Additionally, this find also suggests that the cranial formation of the Acinonyx line is more primitive than the creation of teeth that is found in other cheetah skulls from a similar time period (specifically in the extinct Acinonyx pardinensis and Acinonyx aicha). Thus, the dentition that is characteristic of cheetahs today took longer to evolve and dentition can’t be used as a characteristic in earlier Acinonyx, like the skull they found in China.[2] Although it appears that this new species is probably the most primitive cheetah, it’s important to note that there are more recent ancestors to the cheetah today including the Eurasian cheetah, Acinonyx pardinensis, and the American Cheetah, Mircacinonyx trumani. The giant Eurasian cheetah appears to be the most genetically similar to the living cheetah, and thus the two species likely share a common ancestor (Fig. 4 Acinonyx specific
Ceratopsians and Pachycephalosaurs are closely related in their characteristics. Ceratopsians processed a saddle-shaped boney frill that extended from the skull to the neck and typically had horns over the nose and eyes. The most popular was the triceratops, which could reach over 26 feet and weigh in excess of twelve metric tons. Their frills served as two major functions. It protected the vulnerable neck from being harmed. The second major function that the frill provided was due to the fact that the frill contained a network of blood vessels on its underside, which were used as a means to get rid of excess heat. The Pachycephalosaurs were considered to be bipedal. They were also found to have thick skulls, flattened bodies, and tail that were covered in an array of body rods. Pachycephalosaurs were thought to have been more than fifteen feet long and processed a skull that was surrounded by a rounded dome of solid bone. It was thought that they used their heads in combat or mating contests, but that was disproved fairly recently, which I will discuss later in the paper. Both Ceratopsians and Pachycephalosaurs were “bird-hipped” and both of these suborders contained a backwards pubic bone. Both were Marginocephilia, or “fringed heads”, which is one of three clads under the Orinthiscia order. They were also herbivore dinosaurs that inherited their fringe at the back of the skull from earlier ancestors.(2) Their classi...
The full scientific classification of the giraffe is Animalia Chordata Mammalia Artiodactyla Ruminantia Pecora Giraffidea Giraffa camelopardalis. There were at one time seven species in the genus Giraffa but today only one is still extant: camelopardalis, (Mitchell and Skinner, 2010). Because the modern giraffe does not have any other extant species within its genus, it is helpful to look the phylogenetic tree from a broader perspective. Going beyond the level of genus, the giraffe belong to the family Giraffidea. This family, though, is very small, as it only contains two different extant genera: Giraffa and Okapia, (Lerner and Lerner, 2008) Okapia, or the okapi, represents the closest living relative to the giraffe, and the two are very similar both morphologically and molecularly. The two animals can trace their ancestry back from the “gelocid ancestral assemblage” 20-25 million years to the family Palaeomeridae. From the palaeomerycids arose the Antilocaprinae from the subfamily Dromomerycinae, and two subfamilies of giraffids, the Climacoceratidae and Canthumerycidae. (...
The relationship of the three species and their ancestors can be summarized by looking at the fossils above. It is evident that all of these three species possess fangs and other types of sharp, prominent teeth. These analogous features indicate that there is some similarity in ancestry, since they all form part of the same family group, although they come from different genus. However, there is some difference in the shape of the head. The coyote possesses a straighter jaw and more angular head. The wolf, on the other side, has a wider denture similar to the fox. These three species also share Homologous structures, such as fangs, are present in these species. Another homologous structure is the legs and ribs, since they all have a similar
Majungatholus atopus roamed the plains of northwestern Madagascar about 70 million years ago during the Late Cretaceous (Perkins, 2003; Rogers et al, 2003). The discovery of 21 tooth-marked elements originating from two Majungatholus atopus individuals suggests evidence that the dinosaur supplemented its diet by feeding on its own dead or hunting them (Rogers et al, 2003). It cannot be confirmed whether they were purely scavengers, hunters, or both. Scientists are certain that the marks are not the doing of any other predator because the teeth marks are not consistent with any other known species that lived in the area. Only one other theropod that inhabited the area during the time Majungatholus atopus did, Masiakasaurus knopfleri, had teeth and bite marks too small to have caused these markings. Two large crocodile species also shared the same ecosystem but their teeth were “too blunt and too irregularly spaced to have produced the narrow grooves found on the Majungatholus bones”(Perkins, 2003). The tooth marks on at least nine Majungatholus elements attest to intertooth spacing in the perpetrators jaw and denticle drag patterns consistent enough to make a compelling case for Majungatholus feeding on other Majungatholus (Rogers et al, 2003).
Mountain gorillas where first discovered by a German captain named Robert Von Beringe on the Sabinyo volcano in 1903. The mountain gorilla is the largest of the gorillas, male gorilla’s weight up to 400lbs, and females weight 215lbs. Their life span is about 40 to 50 years. The mountain gorilla became known on 17 October 1902, and is a subspecies of eastern gorilla. It has long hair, jaws and teeth, and shorter arms, than the eastern lowland gorilla. Adult male gorillas grow silver hair on their back and hips, giving them the name silverback.
Hey, I didn’t see you there, how are you?I'm just wondering whether or not a big ol' grizzly bear is going to come charging at me at any point in my life, but seeing as grizzly bears are endangered that probably won't happen. In the past, there were thought to be around 50,000 grizzly bears in North America, nowadays they are growing sparse there are estimated to be only around 1800, now not even a 20th of the population in the past. Most of these grizzlies are located in Yellowstone National Park and Alaska, but they can also be found in Wyoming, Colorado, Idaho and Montana. Some are thought to be in Washington.
Whales are considered to be intelligent mammals, but they live in the water despite the fact that mammals evolved on land. Paleontologist Phil Gingerich has been studying the evolution of whales since 1978. In 1978, he and his team discovered a rock in Pakistan with a skull on the inside. The skull appeared to be a wolf-like animal upon first sight, but Gingerich noticed the distinct whale ear on the skull. The skull, which had characteristics of both whales and other mammals, was that of a common ancestor of the whale known as Pakicetus. Many scientists believe that Pakicetus resembled the seal in its appearance. Pakicetus could not be considered a whale, since its backbone and limbs do not have similar features to those of a whale. Therefore, it is considered an ancestor of the whale, since it has some features of the whale and some unique features (or features of other mammals). Today’s whales have mammalian characteristics, which prove that they have evolved from a common ancestor of the mammal. A whale’s fin also has traits that are common of many species. The fin seems to be similar to that of a fish, but the bones on the inside of the fin are similar to those on a bird’s wing, a monkey’s arm, and a frog’s limb. This seems to be proof that these organisms, and many others, all evolved from a common ancestor. Other proof that whales have evolved over time lies in Egypt in the Valley of Whales, where over 400 fossils of whales currently lie. The desert used to be a large sea that was home to a few kinds of whales. In the Valley of Whales, Gingerich discovered the Basilosaurus, which had small hind legs, toes, and a mobile knee and lived 35-41 million years ago. This fossil is considered to be a transitional fossil, since it ha...
All primates have essentially the same kinds of specialized mammalian teeth adapted to eating a wide variety of foods. Beginning at the front, each quadrant of the mouth has 2 incisors, 1 canine, and varying numbers of premolars and molars. The incisors are used like scissors for nipping off pieces of food. The pointed canines are for piercing and tearing. The premolars and molars, with their cusps, are used to grind and smash food. In platyrrhine species, there are 3 premolars and 2 or 3 molars. This results in a dental formula of 2.1.3.2 or 2.1.3.3. In contrast, all of the catarrhines have 2 premolars and 3 molars, making a dental formula of 2.1.2.3. The chimpanzee shown below is an Old World anthropoid species and, therefore, has a catarrhine dental formula.
The gorillas live mainly in coastal West Africa in the Congo, Zaire, Gabon, Equatorial Guinea and Cameroon. Gorillas live in the rain forest. They usually live on the ground but build nest in trees to sleep in. Gorilla troops keep a 15-20 square mile range which often overlaps the range of other troops. There are three different kinds of gorillas. The eastern lowland gorilla the western lowland and the mountain gorilla. They are herbivores and eat only wild celery, roots, tree bark pulp, fruit, stems of many plants and bamboo shoots. They spend nearly half their day eating.
The iconographical analysis is now applied, starting with pre-iconography. This painting shows a a cheetah with a woman’s head lying on a rock in the centre. She has long red-hair and both eyes and mouth closed. On the left there is a man with a cloth wrapped around his waist standing on a lower ground. His left elbow rests on the rock and his head lays against the cheetah’s whose left paw touches his torso.
The fossil record of horses extends back to an odd-toed ungulate mammal belonging to the taxonomic family Equidae, a dog-like ancestor 55 to 42 million years ago in the genus Hyracotherium in North America. Hyracotherium had a primitively little face , four-toed forefeet, three-toed hind feet, an arched back, small brain, and higher hindquarters than forehand. Later genus has increased in body size, brain complexity, the size of cheek teeth, lengthening of the face, and reduction of toe number. However, even though horses got larger over time but these trends are not seen in all of the horse lines. Genus such as Hipparion existed from 23 to 2 million years ago, showed gains in size, But some later genus such as Archeohippus, and Calippus got smaller again (Boundless, 2016),(Encyclopedia of Life,2015), (equineworld.co.uk, 2014), (Molen, M.
When an average person thinks of a Cheetah they think of quickness, agility and elusiveness. All of these traits can be associated with an exhilarating experience. The fa...
Welsh, Jennifer. "Fossil Teeth Show Mammals Thrived Before Dinos Died." LiveScience. TechMedia Network, 14 Mar. 2012. Web. 14 Mar. 2014.
The increase in brain size may be related to changes in hominine behavior (See figure 3). The third major trend in hominine development is the gradual decrease in the size of the face and teeth. According to the Microsoft Encarta Encyclopedia ’98, the fossil evidence for direct ancestors of modern humans is divided into the category Australopithecus and Homo, and begins about 5 million years ago (See figure 1). Between 7 and 20 million years ago, primitive apelike animals were widely distributed on the African and, later, on the Eurasian continents (See figure 2). Although many fossil bones and teeth have been found, the way of life of these creatures, and their evolutionary relationships to the living apes and humans, remain matters of active discussion among scientists.
Sikes, Roberts. and William L. Gannon. "Guidelines of the American Society of Mammalogists for the Use of Wild Mammals in Research." Journal of Mammalogy 92.1 (Feb. 2011): 235-253. Academic Search Premier. EBSCO. Web. 5 Oct. 2011.