The background of this article gives information that is necessary to understand the experiment. The shape of the pelvic girdle is an appropriate predictor of both phylogeny and movement in terrestrial vertebrates. However, in marine vertebrates, the gravitational forces typically applied to terrestrial pelvic girdles are not there and therefore have little impact on the shape of the girdle. Pelvic girdles of fish are generally not attached to the vertebrae and primarily are used as a place for muscles to attach and supporting of the fins. The authors discuss how in many cases the pelvic girdle could be removed and not result in any complications. However, there are some marine vertebrates that are capable of bottom walking on the ocean floor with their fins. In batoids, the pelvic fins are used for walking, which is when pelvic fins move in an alternating fashion, or punting, when both pelvic fins move at the same time. There is also augmented punting; this is when the vertebrate uses both the pectoral fins and the pelvic fins to generate more thrust, this action decreases the forces on the pelvic fins during a punt. While this locomotion would …show more content…
require less support of the body by the pelvic girdle than terrestrial locomotion, there are still small forces that apply. There are small forces that act on vertebrates who preform augmented punting; however, this form of locomotion requires less support of the body by the pelvic fins. Besides walking and punting, there are also many batoids that swim. There are a few forms of swimming that batoids utilize: axial undulating, pectoral undulating, pectoral oscillating, and pectoral intermediate. The authors compared the two modes of locomotion, along with the order and family the batoid belonged to, in order to see if there were significant differences in the shape of the pelvic girdles within these classifications. The goal of this experiment was to determine if the shape of the batoid pelvic girdles would vary with punting ability. In conjunction with this the hypothesis of the study was that the batoid pelvic girdle shape correlates with the locomotor mode. In order to study the different pelvic girdles of batoids, the authors utilized fossils and extant species. The data of extant species came from reference material that provided them with the mode of locomotion used by the specific batoid. The fossils and extant species were then organized into groups based on phylogeny and the form of locomotion. Three of the four orders of Batoidea and many of the different family of batoids were used to complete these experiments. The authors used various methods in order to gather data about the differences in the pelvic girdle of batoids. First, the general shape of the pelvis was analyzed. In order to do this similar structures and certain maximum and minimum points, as well as two sets of semilandmarks, were placed along the outline of the pelvic girdles. These specific coordinates were recorded and converted in a software program to generate an image of the pelvic girdle. The authors then addressed variations in the pelvic girdles of the batoids. In order to compare each of the pelvic girdles to the same set of coordinates, the authors created a consensus girdle, which was an averaged girdle shape. All of the pelvic girdles were compared to the consensus girdle and partial warp scores for every batoid were generated by overlapping the image of the pelvic girdle and the consensus girdle. The partial warp scores were then used to create relative warp scores, which relate to changes in the shapes of the pelvic girdles. The results of these revealed that the first three relative warp scores produced 88% of the differences in the shapes of the pelvic girdles. Relative warp number one corresponded to changes of the lateral and prepelvic processes. Relative warp number two corresponded to changes in the height and length of the puboishiac bar. Finally, relative warp number three corresponded with the curves of the most lateral edges of the pelvic girdle. When the authors compared the different types of swimming and punting, they found that there was variation within the subgroups of each of the categories. The authors determined that the three order categories were significantly different from one another. They also found that only three of the families were significantly different, the rest had no differences that were significant. When they compared the subgroups of the swimming mode, they found a significant difference in pectoral oscillators and axial undulators from the other swimming modes. Finally, the authors determined that all modes of punting were different from each other. The authors then grouped the similar shaped pelvic girdles within the multiple categories to determine if simply based on the shape of the pelvic girdle they could determine the correct category the batoid belonged.
They found that their groupings of similar shaped pelvic girdles fell into the correct category, except at the family level.
The results from the experiments supported the hypothesis that the batoid pelvic girdle shape correlated with the type of locomotion. They found that the form of locomotion utilized by the batoid had a greater determining factor on the shape of the pelvic girdle compared to the phylogeny. An important discovery of this experiment showed that the shape of the pelvic girdle of a batoid can be used to predict the swimming and punting mode, and the order to which the vertebrate
belongs. I think that this was a well written article that had a lot of information. However, it was relatively difficult to read; I read through it multiple times in order to fully understand the article. The authors used a lot of abbreviations that you had to keep track of so you would not get confused. My main critique would be that authors included the different swimming modes in the experiment, but they did not mention them at all in the background information. This made it seem really random when they came up in the results section, and I had to do my own research of the swimming styles so I would no longer be confused. The authors state that the goal of the experiment was to determine if the shape of the batoid pelvic girdles would vary with punting ability. This statement does not include anything about the swimming modes. I feel like this could have been better incorporated in the experiment and it would have made things more clear. However, these few errors did not ruin the paper; it was still a well written and informative article.
Study done from the available fossils show that the body of Liopleurodon was very streamlined and adapted to swimming. Its body had four limbs which were paddle-like in shape. These paddle shaped limbs acted like propellers which made it
Orca whales do not like to be taken from their family, held captive for many decades and put with other whales that they do not know. No other living organism on this planet would like to be put through the same thing. Orca whales are highly social animals, they are very intelligent, and are very emotional. If they are kept away from other whales, fed intermittently and received little attention from staff makes them get very emotional and can lead to death of people and the whales. Orca whales should not be held captive; they are beautiful creatures that are not great for people’s amusement and if they are treated poorly, they will act poorly.
Seahorses are a prime example of species whose atypical biology and unusual global distribution leads to a series of evolutionary questions. Seahorses (genus Hippocampus) are a marine species that have extensively been studied because of their abnormal behaviors in the marine environment compared to other marine creatures. Many of the seahorse species have large ranges, both longitudinally (over a great horizontal distance across the ocean), and latitudinal (great vertical distance within the ocean), regardless of the fact that they are characterized as weak swimmers and lack any large structural fins for efficient swimming (Lourie et al., 1999a). Although they do have these large range environments, seahorses
Sarai Michel English 9HP, Period 4 When I was six years old, my parents took me to SeaWorld for the first time. I remember clearly watching the Shamu show and sitting in the splash zone, ending up soaked in water by the end. But I also distinctly remember wondering how an animal so big and beautiful could ever be happy in such a small tank, so far away from home. The animals could never possibly experience the joy they would have out in the wild where they belonged.
In the early 1800’s, a new discovery that left paleontologists in awe was the fossil finding of the immeasurable amount of species of reptiles, Ichthyosaurs. Greek for “fish lizards”, these fossils were found all over the world. Because these large aquatic reptiles migrated just as whales do today, paleontologists have had the amazing advantage of collecting fascinating bone fragments throughout the past 177 years. Ichthyosaurs swam the ocean life from about 245 million until about 90 million years ago- approximately the same time dinosaurs ruled the land. The earliest Ichthyosaur fossil findings were in parts of Canada, China, Japan, and possibly Thailand. Countless fossils came from coatings of limestone produced out of the ocean-floor ooze that was predominantly superior at preserving very well facts of the creatures it digested (Perkins 2).
Although the Hippocampus spp. are placed into the same class as other organisms more traditionally viewed as fish, their morphology bears distinct differences in comparison to other bony fish. The various species belonging under the genus Hippocampus range in maximum size from 20 mm to 300 mm(Foster 8). Their physical appearance is distinct from other members of its class due to their "horse-like head, monkey-like tail, and kangaroo-like pouch."( Lourie et al 12) Morphologically, seahorses do not have scales like traditional fish, but rather posses bony plates covered by skin. The appearance of bony extrusions and skin ...
There are many different ways to show off your equines skill and ability and competitions are one of them. For years humans have been entering their equines in competitions to show off their grace, beauty, and strength. There's an abundance of competitions to show off your equestrian and each require a different type of training, horse, and skills. Three of the more popular competitions are rodeos, dressage, and show jumping. These competitons can include either speed, agility, skill, or even all three at one time!
Would you like to try a dog limb with the salad? These are the exact word that I heard from the Korean air hostess when I was first traveling to the USA. I still remember she passed me a wrong serving plate. This incident really affects me a lot because I had never seen meat before in my life. It makes me think about how the meat industry is widely spread and how it is regulated by the governmental agencies. Factory farming is a system of rearing livestock using intensive methods by which poultry, pigs, or cattle are confined indoors under strictly controlled conditions. Today, factory farming dominates the U.S food production to fulfill the excessive demand of the peoples. Most of the factory farms are run by the giant corporations and their
Everyone has a family member, friend, or beloved pet so sick you were not sure if they would live or die, and you find out about a new surgery procedure or medicine available to save them. Have you ever wondered where these new surgery procedures or medicines come from? When you think about all the major medical advancements over the last few decades and beyond, it has depended on animal research. As research moves into the future, we need to understand how the body works and how diseases progress. We need to find ways to treat, cure, or prevent disease and disability. The use of animal research is providing us with new technologies and medicines, which are benefiting both humans and animals in treating and extending lives.
You wake up in the hospital, look around, and find a doctor hovering nearby declaring that you have just suffered through a heart attack; affirming that if not for your dog, you would have died. You remember back to earlier that day: sitting on the couch, feeling a little off, hearing your dog barking, sensing him nudging you, going to the phone to call the ambulance, and having your dog by your side until you were safe inside the aluminum walls of the emergency vehicle. Although it sounds abnormal that a dog would be the one to save someone’s life, situations similar to the one above are not uncommon. Dogs and other household pets have been shown to be able to detect medical emergencies, including heart attacks and seizures, in their owners.
Taken from the only place you've ever known. Away from the only family you have. Kept in crates and cages to be sold. Removed from their home, exotic animals are put in yours for personal amusement.This act is ruinous an inhumane, it violates the basic rights of human and animals. Exotic animals have a rightful place in their natural habitats, not as pets, because they endanger the community, become sick, and their owners abandon them.
Animal cruelty is an issue that gets plenty of attention in the U.S. From all the commercials to the donation hotlines and tee shirts everyone in the states knows that it is a relevant issue, but what about testing on animals? It’s not as relevant or discussed as other forms of cruelty, but the truth is we kill thousands of innocent animals all for the hope that maybe a wrinkle or two may disappear. This is horribly insensitive and cruel and I really can’t believe that we could do this to such innocent and loving creatures. We have to accept that animals are not ours. Cosmetic testing on animals is not only cruel but illegal in several countries; innocent animals are constantly losing their lives for our vanity.
Humans domesticated dire wolves Canis lupus as early as 26,000 years ago. The real question here is why wolves. If you really think about it there are other animals out there that seem to be a much better choice for humans to utilize as hunter companions. Take the chimpanzee for instance it has hands and pose able thumbs. Seems like a chimp would make a great companion we could even teach it to use tools to aid itself in the adventures we send it on. Instead we chose to domesticate a vicious wolf that you know was not a easy venture. I think a chimp would have been a much easier task to do however we chose the wolf you ever wonder why? Well in my research I found it was a pretty easy decision but it was its shear ability to work well with
Conversely, bipedalism in non-avian theropods entails rotation of the pelvic limb and power input from large tail-based muscles; in particular, the caudofemoralis longus (CFL), which is attached to the fourth trochanter (a diagnostic feature of the majority of archosaurs, which maniraptorans and birds lack completely). This form of locomotion is often characterised as “hip-driven” and is seen in today’s crocodiles, with the caudofemoralis longus, attached on the fourth trochanter, serving as an important locomotor muscle. This is likely to be the mechanism of locomotion that the primitive archosaurs used, since the majority of limbed reptiles locomote in a similar manner. In birds, the caudofemoralis longus is either a very small muscle (as shown in our results, in which the caudofemoralis longus had the lowest mean muscle mass), or has disappeared
People in life have different responsibilities and different rankings. The President of the United States is treated equal with the Vice President while an elementary school teacher will not be treated with the same equality.People treat their animals this way. They treat the animals equally threw food and water and shelter, but they pamper some more then others, they have favorite’s, people do this all the time. All animals are equal, but some are more equal than others.