Sharks Have Been On Earth For Over 400 Million

Sharks have been creatures that can date back to over 450 billion years, and have survived through all disaster and still live on Earth today. This is a great feat for anything to stay in existence for that amount of time, and hopefully sharks can continue to live on this Earth and not go extinct. There are hundreds if not thousands of species of shark from when they first swam Earth’s oceans to when they continue to swim the same oceans. The study of sharks is a very interesting and extraordinary topic, being able to put together images of what sharks used to look like compared to sharks now is just amazing. In this vast amount of time sharks have spent on this Earth there has been many things that has changed, through evolution and adaptation. Through research and personal opinion I plan to show how sharks have evolved, what has changed through evolution and the history of

Sharks are aquatic creatures and very important to the living with lots of information humans may not understand. To start off, femeles give birth to 7-9 sharks per litter that are 3-4 feet at birth. Next humans believe all sharks are monsters but out of 400 species only 4 sharks have been claimed to attack on humans. Lastly sharks attack for 2 main reasons one reason is for defense and predation. They attack in defense when humans are in or around their territory they attack in predation mistaking people for seals. In conclusion sharks are creatures that humans are still learning about and try to understand them better.

Both these sharks feed on fish and the Great White is also known to feed on larger prey. The Great White Sharks have been known to attack humans swimming and surfing in the seas. The Tiger Shark is approximately 4.5 meters long and has a reputation for eating a wide range of animals and even inanimate objects. They have found license plates in the stomach of a Tiger Shark. Because of its discernment regarding food, this shark is one of the most dangerous ones for human attacks. The Sand Tiger Shark, not to be confused with the Tiger Shark, even though large, is relatively peaceful and will only attack if provoked. The Nurse Shark will reach approximately 4.3 meters and favor shallow temperate waters. The Blue Shark prefers the deep, cooler waters of the tropical and temperate oceans. They can give birth to large litters from 25 to 100 pups at one time. The Mako Shark vary in length between 2.7 to 4.5 meters. These sharks are in the same family as the Great White Sharks so they can be fairly aggressive. The most aggressive shark is the Bull Shark. This shark is known as being unpredictable and aggressive even towards humans. Many of the attacks and fatalities recorded each year is from this shark. The Bull Shark is found in warm, shallow waters and can live in both freshwater and saltwater environments. In fact, it is said that JAWS was based on a Bull Shark, but since the Great White is a better looking,

Sharks have been in our oceans for almost 450 million years. Those millions of years of evolution have allowed many different shark species to develop abilities, and to become perfect predators.

Every Jaws fan knows the shark gets it in the end. What they do not know is that too many sharks have gotten it; and that has caused a rapid decline in the shark population over the past thirty years. Since the 1970's, sharks of the Atlantic and Gulf of Mexico shores have declined eighty-five percent. Sharks are vital animal to our world's ecosystem, and if the decline is not controlled; we could be facing devastating problems in years to come. Information has been obtained from two books: The Shark Almanac by Thomas B. Allen and Sharks, An Introduction for the Amateur Naturalist by Sanford A. Moss. Sources also include a number of online references, among them BBC News, ENS News, The New York Times, and two online scientific

Adapted for a wide range of aquatic habitats, various shark species inhabit shallow coastal habitats, deep-water ocean floor habitats, and the open ocean. With a wide selection to feed off of, as a whole the shark species feed on just about everything. Their diet consists of fish,

Sharks are one of the oceans top predators. They vary in size from the extremely small dwarf shark, to the colossal whale shark. Sharks can be found all across the world’s oceans, from the tropic waters of Hawaii to the sub zero temperatures in the Artic oceans. Of the hundreds of sharks a select few species have actually been recorded in the Artic. Of these few, only three of them spend the majority of their time in these harsh, freezing waters. These sharks are the Greenland, Pacific Sleeper, and Salmon sharks.

Beginning with the simplest one-celled organism, an extraordinary animal rose in the murky waters entitled to a non-comparable killing-eating machine. This organism has become nature’s most genuine and most successful creature that it has remained unchanged for over 250 million years. Nature finally invented the perfect king of the sea. This animal has given the sea it’s “living” adjective; in turn, it was entitled—the “great white shark.”

Sharks have been in existence for more than 300 million years. Their evolution occurred over 150 million years earlier than that of the dinosaurs. Most of the existing fossil data of early sharks was collected from fossilized teeth together with several skin impressions. primitive sharks (Cladodonts) , had teeth which were double-pointed, up to 2metres in length, ate fish as well as crustaceans, and existed approximately 360 million years ago.

The Australian Grey Nurse Shark is also known as the Spotted Ragged-Tooth Shark and as the Sand Tiger Shark ("Australian Threatened Species”). The species is identified by its gray to gray-brown coloration, the possible presence of reddish/brownish spots on the caudal fin and posterior half, their countershading, and by its two almost equally sized dorsal fins. They are known to grow over 3.6 meters in length with the males and females maturing at different lengths, 2.21 meters and 2.2 meters, respectively (McGrouther, 2015). Females also mature significantly later at 9-10 years than their male counterparts, who mature at 6-7 years. Their diet consists of fish,

This article talks about what sharks does in order to survive and what are they capable of doing. According to the article, sharks do not sleep; but rather, they have rest periods throughout their day. Sharks are capable of hearing anything below 1000 Hertz and can also swim up to 20 mph. Sharks skeleton is made up of cartilage rather than bone. According to the article, cartilages are lighter than bones. What keep them from floating are their large livers. Sharks can gather and keep the air into their stomach to keep them from floating.

Stewart’s mission was to bring public awareness to the dwindling shark populations. His work was meant to bring change to public policy, as well as to educate the public. Prior to Stewart, many were unaware that conservation programs were needed to protect sharks. Sharks are pivotal to marine ecosystems as apex predators. Sharks have played a major role as predators for hundreds of millions of years. One of the major contributions these apex predators have made to their ecosystem is the evolution of their prey spanning back to the dinosaurs. While sharks have remained relatively unchanged for hundreds of millions of years, their prey has been continually evolving. Stewart’s recent death displays a story that must be told of one man’s journey to protect the most feared and misunderstood creature in the oceans.

Recent studies from the article “Hammerhead shark migration gives new hope for conservation” discusses how these hammerhead sharks have been listed onto the IUCN (International Union for the Conservation of Nature) since 2007, also having certain regulation about international trade threatening species going extinct. Dr. Tristian Guthridge explains the benefits of understanding the shark’s behavior and more research of where these sharks are migrating, and possibly manage the time of fishing in the areas to eliminate human and shark altercations. With the wide spread of ocean water it can be difficult to study the traveling of sharks; however, the research group was able to tag the sharks “with both acoustic and satellite tag, and use photo identification and laser photogrammetry” (Charlie Huveneers).

In the more recent Miocene era and Pliocene era, approximately 16 to 2.5 million years ago, the Carcharocles megalodon roamed the world’s oceans (Pimiento & Clements, 2014). A complete C. megalodon skeleton was never discovered, but a trend in size increase along the megatooth lineage suggests that the species could have reached a length of up to 60 feet (Pimiento & Balk, 2015). This makes the C. megalodon the largest shark known in existence. In addition, typical adult C. megalodon teeth measured 15 centimeters in length (Bendix-Almgreen, 1983). A closer analysis of the teeth reveals a serrated crown with approximately 13 nodules per centimeter (Bendix-Almgreen, 1983). The size and morphology of a C. megalodon tooth indicates that the species

Sharks are one of the most feared carnivores in the sea. There are 365 species of of sharks in the sea as we know today. All sharks are carnivores. Most of them eat live fish, including other sharks. A shark's most common natural enemy is an another shark. Most sharks eat their prey whole, or they tear off large chunks of the bodies. Some sharks crush their prey. Others take out small pieces off flesh from large fish. Sharks also feed on dead or dying animals. Sharks have the reputation of attacking human beings. But less than 100 shark attacks a year are reported throughout the world. Sharks are most common in warm seas and oceans. Whale sharks, are the largest shark known to man. Sharks are classified in the order