David Attenborough's Journey Through The World

It all started when the shipping container we were riding in from the United States to England fell overboard. It plummeted into the ocean floor and busted open when it crashed into the flattest part of the ocean. We floated up through the three ocean zones to the surface of the ocean. On our journey from the Midnight zone to the Sunlight zone, we saw fascinating ocean creatures and various plants. Starting from the Midnight zone we noticed fewer plants and animals than the Sunlight zone due to its cold temperatures. Most of the animals looked like as if they were to belong here and there was absolutely no sign of plants. But, we also noticed fewer creatures which adopted very well to these cold and freezing temperatures. Most of these temperatures happen in the deep sea trenches, Abyssal plain, and the Continental rise.

This allows us to see, up close, the transformation of animals. What was once isolated to only the sea, evolved into something that could now dwell on land as well. Throughout the course of history, more and more evolutionary traits will occur allowing different species to prosper where they once could not.

The author and his colleagues specifically chose to focus on 375 million year old rocks in their search for fossils because this was the time frame that provided fish that would be useful to study from. The 385 million year old rocks provided fish that look too similar to the ones we have now and the 365 million year old rocks have fossils that don’t resemble fish. The 375 million year old rocks, however, provide fossils that show the transition between fish and land living animals.

In order to find evidence of the transition from fish to land animals, the author and his colleagues chose to focus on 375 million year old rocks. In 2004, they studied sedimentary rock on Ellesmere Island in Canada’s Arctic as they thought that the rocks there would be exposed and untouched by humans, which would be ideal for fossil excavations. They studied sedimentary rocks (limestone, sandstone, siltstone and shales) because these

1. Neil Shubin, author of Your Inner Fish, and his colleagues travel to Ellesmere Island to look for and study the shift from fish living in water to creatures living on land (4). Fossils from 360 million years ago include amphibians and reptiles. Fossils 385 million years old, only fish are found. Because of this, Shubin and his colleagues look at the time in the middle of this, 375 million years ago (10). In 2004, they give it another try, after failed previous tries (21). What gradually emerges from the rocks they searched for in the bottom of the quarry is an “intermediate” right between fish and land animals, Tiktaalik, “large freshwater fish” (22-25).

The Ocean is 70 percent of the earth surface, humans have explored less than five percent of the ocean, and is home to innumerable amount of living organisms. One of its oldest inhabitants is the Cheloniidae dates back to the Triassic era, roughly 250 million years ago, (Wang et al.,

<b>Introduction</b><br>Think of a world which existed 290 million years ago. As you look out over the terane in front of you, you think that you are on an alien planet. You see volcanoes spewing ash and lava. Beside them is the ocean which is swarming with many different species of echinoderms, bryozoans and brachiopods. As you look down onto the sea floor you are amazed at the countless number of starfish and urchins. Some animals leave you can't even describe and you have no idea even what phylum they belong to. This is a world at its height in diversity of oceanic species. Millions of wonderous species existed at this time in the ocean and most of them will never appear again in earth's history. In the geologic time scale, a million

Just last year, some researchers stated that the extinct aquatic animal, the ‘Tully Monster’ was a vertebrate, possibly a relative of today’s lampreys. Like a mismatched puzzle, the Tully monster lacks some vertebrate pieces and has others that are the wrong shape, researchers and colleagues report in the March issue of Palaeontology. (Palaeontology includes the study of fossils to determine organisms' evolution and interactions with each other and their environment, their paleoecology).

Some 480 million years ago, way before the dinosaurs, the Ordovician period, was the period when plants were finally able to inhabit land. It lasted for 42 million years. Sea levels were very high during this time, which allowed the already present sea creatures to grow to even larger proportions.

The author and his colleagues chose to focus on 375 million year old rocks in their search for fossils because amphibians that look dissimilar to fish were discovered in 365 million year old rocks, while fish without amphibian characteristics were discovered in 385 million year old rocks. Thus, it is possible that the evolutionary intermediary, or the “missing link” between fish and amphibians, would be discovered in 375 million year old rocks, between the two time periods. The rocks examined were sedimentary in composition, as the gradual and relatively gentle formation of sedimentary rock under conditions of mild pressure and low heat are conducive to the fossilization of animal remains. Sedimentary rock is also often formed in rivers and seas, where animals are likely to live. This site provides a resource that describes means by which fossils are formed and how the fossil record may be interpreted, and shows some examples of fossils demonstrating evolution through geological periods: http://www.fossilmuseum.net/fossilrecord.htm. In 2004, Shubin and his colleagues were looking for fossils on Ellesmere Island, in northern Canada. This location was chosen because of its lack of human development, as well as of obstructing natural formations and life forms such as trees, which

First, the author introduces "Free-Swiming Predators" theory. According to this theory, since many other primitive arthropods were hunters, it is possible that Agnostids had been predators as well. However, the professor refutes this idea by referring to the fact that since vision is a very important tool for hunters, they usually have large eyes. On the other hand, fossil evidence actually shows that Agnostids had small eyes

Since Geology and fossils was such a broad subject, I narrowed it down to marine plankton. The article I read was written by Jorg Mutterlose. It was about the study of how micro plankton play a key role in understanding the marine biosphere in present day oceans. All understandings about ancient marine systems (fossils) must have a back ground of plankton systems and its role at the base of marine food chain. Basically that is saying the ocean organisms started out as plankton. Author Jorg Mutterlose addressed that they wanted to inform their readers about recent trends and scientific issues in the evolving field of marine plankton. Marine plankton include the oldest eukaryotic organisms which made their first appearance 2.1 million years ago.

A new prehistoric relative to modern day crocodiles, Ieldraan melkshamensis, has recently been identified. The fossilized remains of this 10 foot long ancient reptile has been in Londons Natural History Museum’s archive for almost 150 years and was classified as a new species due to the many unique features of it cranial anatomy. The primary characteristics that distinguishes this fossil for all the other known prehistoric species are the features of its skull, lower jaw, and most importantly its teeth. These features are thought to have allowed this predator to feed on large prey, such as squid, making it one of the top predators in the oceans of jurassic Britain. It was originally thought that this family of prehistoric crocodiles were present during the late jurassic period between 152 and 157 million years ago, but this fossil has been dated back 163 million years, making it millions of years older than this family was previously thought to be. This discovery is incredibly important for our understanding of the evolution of these ancient animals and how they impacted their marine ecosystem.

These techniques led to the discovery of the boundary between the two eras. A single thin layer of clay found within predominantly limestone rocks established this. By comparing the marine life found in, above, and below the clay, the marine life, like the dinosaurs, had been terribly affected by the extinction event. The percentage of life in the upper layers was dramatically lower than that in the lower. This was far more compelling than what was suggested by dinosaur’s fossils.

Sponges evolved by extending the choanoflagellate way of life to large size and sophisticated packaging. They continued to pump water (and the oxygen and bacteria they take from it) through their tissues, in internal filtering modules.