Following the Paleocene Epoch is the second stage of the Paleogene or Tertiary Period called the Eocene Epoch. The Eocene Epoch was marked by the dominance of angiosperms and the continuation of mammals as a result of radiation. The Eocene Epoch lasted from 57 to 35 millions of years ago. Being the second stage of Earth where there were no dinosaurs meant that there was a lot of room for other, previously less competitive species, to prosper. This epoch began as a result of the methane gas leak from under the ocean floor during the Paleocene Epoch. Due to the extinction of animals during the late Paleocene Epoch other organisms in the Eocene Epoch had to reorganize themselves to make sure that they were not the next organisms to be extinct. Fossils from the epoch are spread widely demonstrating the range of organisms found during the time.
The animals that lived during the Eocene Epoch were a result of the extinction of their predators and also the evolution of species to accommodate changes in the environment. For instance, radiation released in the Northern Hemisphere caused not only more mammals to emerge but also for them to increase in size. The average mammals now weighed about twenty pounds according to their fossils. Moreover, a change in temperature during the later portion of the Eocene Epoch caused other animals, not just mammals, to increase in size in response to the cooler climate. Not only did the animals get bigger but the temperature change also changed the habitats from being a lot of forests to more grasslands. Besides the temperature change, most land bridges between continents remained so that animals could move freely among most continents, excluding Australia. New sea animals include mollusks and the first ...
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... of tectonic plates that caused fault lines to move. This shift had a massive effect in changing the water currents of the oceans and even possibly influencing the atmospheric temperature.
The Eocene Epoch ended about 35 million years ago allowing the third epoch of the Cenozoic Era, the Oligocene, to begin. The end of the Eocene Epoch can be considered to be a facto of the plate movement observed above. Not only did the plates move but they also resulted in a distinct change in the temperatures observed in the atmosphere. The average temperatures suddenly cooling caused the overall climate to leave the moist, subtropical level and become very dry. The ice caps returned to the North and South Poles of the Earth. This form of cooling affected many organisms causing them to become extinct but also allowing for different types of habitats, like woodlands, to be made.
In this paper Martin is arguing that late quaternary or near time extinctions where caused by human activity or as he calls it “overkill”. Martin recognizes that there have been many forces that have triggered extinctions in the planet on the past but disagrees with the idea that near time extinctions where caused by some commonly believed causes like climate change, disease or nutrient shortage. He argues that the arrival of humans to different continents, islands and the subsequent excessive hunting, the introduction of diseases and other competitors and predators was the cause of extinction of a great number of species “As our species spread to various continents we wiped out their large
The biggest mass extinction of the past 600 million years (My), the end-Permian event (251 My ago), witnessed the loss of as much as 95% of all species on Earth. Key questions for biologists concern what combination of environmental changes could possibly have had such a devastating effect, the scale and pattern of species loss, and the nature of the recovery. New studies on dating the event, contemporary volcanic activity, and the anatomy of the environmental crisis have changed our perspectives dramatically in the past five years. Evidence on causation is equivocal, with support for either an asteroid impact or mass volcanism, but the latter seems most probable.
Scientists had some idea to the evolutionary process of whales. “It has always been clear that aquatic cetaceans must have evolved from terrestrial mammals and returned to the water, and the forelimbs of recent cetaceans still have the same general pattern as that of land mammals.” (Walking with Whales) It was known fact that land mammals and whales were related. However, the change from ancient whales to modern whales is drastic.
...iod. The glacier formation led to the enormous decrease of the sea level which dried out the swamps. Swamps form because of the water level was high and flooded the forest so the low sea level really affected the huge swamps areas of the Carboniferous period. The climate changed from hot and humid to cool. The plants couldn’t adapt to this change so most of the ones that flourished during the time period died off but it led to new plants forming. Most of the amphibians that were prosperous during this time also couldn’t adapt to the environmental climate change so most died off. The insects also couldn’t live through the change. The reptiles however made it through the climate change. They were able to adapt unlike all the other species they lived with during the carboniferous period. These environment changes eventually led to a new time period, the Permian Period.
This breaking up of the mega continent of Pangaea allowed for more diversification of plant species and as the continents continued to break apart, plant life became even more diversified. As the continents shifted and moved from one area of the ocean to another the climates began to change drastically which allowed for plant and dinosaur species both to begin adapting to suit their new ecosystems. All the water that was produced by the split of Pangaea gave the previously hot and dry climate a more humid and drippy subtropical weather. Dry deserts took on a greener look. Before the Mesozoic Era, livings things were confined to only surviving in the oceans. It was not until the Jurassic Period that livings things evolved the capability of living on the land rather than just the ocean. Towards the beginning of the Jurassic, plant life evolved from Bryophytes, the low-growin...
Throughout Earth’s history there have been many changes. These changes have consisted of temperature fluctuations, atmospheric differentiations, extinctions of various plant and animal life, etc. Over time everything seems to have evolved in some way form or fashion. However, the Permian Era extinction was different from all the rest. This extinction affected every form of life, but especially the marine life. Researchers have stated that 93-97% of all Earths species went extinct during this period of time. This essay will explain how a once blossoming progressive era turned into Earths most catastrophic event.
When and why did Homo Sapiens begin to grow into a thriving population that have produced both cognitive and technological advances? No one knows for certain and because of this question countless amounts of people have decided to become anthropologists. Anthropology is defined as, “the study of human beings and their ancestors through time and space and in relation to physical character, environmental and social relations, and culture(Merriam-Webster). Despite all of the time and effort that anthropologists have put into discovering the correct response, the answer to this question is constantly changing because population, cognitivity and technology are constantly changing too. One way to determine how these factors affect Homo Sapiens is by studying past societies. The development of technology expanded rapidly in the Upper Paleolithic era. The technological and cognitive advances made by the growing Upper Paleolithic people changed their lives for the better and allowed them to adapt to their environment in innumerable ways.
That “prehistoric” whales had the jaw of a wolf (a fifty million year old wolf to be exact) and the ear of a whale. I think that all of our semiaquatic mammals play a big part in the evolution of land mammals to water mammals. Like at some point of say an otter’s life, nature told it to stop evolving so that it wouldn’t become completely marine, but semiaquatic as we named it. How did it know when to stop evolving? Was it changes in the environment? Or the need for survival? Which brings around another question, how did we go from a planet of just rock and magma, to a planet thriving with
The most significant event of the Cretaceous era came at its end. Nearly 65 million years ago, the second most severe mass extinction in earth’s history occurred. This resulted in the loss of around 80% of species living at the time. Though nowhere near as severe as the end-Permian mass extinction, the end-Cretaceous extinction is the most well known mass extinction event. This is due to the violent event that caused it the extinction, as well as the chapter of earth’s history that it closed: the Dinosaurs. The Cretaceous Event ( often shortened to K-T event) Of the animals that were killed off were the flying reptiles (pterosaurs) and the last few mosasaurs and plesiosaurs, both early marine reptiles. Many mollusks and species of microscopic plankton were killed. Terrestrial plants suffered mass extinction as well. Almost 60% of terrestrial plants were lost. This led to high extinction rates among insect populations, especially insects that were highly specialized to feed on just a few types of plants had it the worst. It took approximately 9 million years for the global insect populations to recover from the Cretaceous extinction. Immediately after the extinction, the earth saw an explosion of short term species who respond well to fire, or other external disturbance. Evidence of the catastrophe comes from a thin rock layer deposited worldwide just after the impact. It is dominated by fossil plants whose descendants recover quickly after fires of other disturbances, such as Fire Weed in Alaska. The causes of the Cretaceous extinction are still being debated by paleontologists. Scientists agree that the main cause of the extinction was a...
The separation of the Paleolithic and Neolithic Ages mark a great divide in the lives and cultures of prehistoric peoples. Many aspects of everyday life were modified to suit a new standard of living. Society, Economy, and Technology were greatly affected by the "Agricultural Revolution" that spawned the Neolithic Age.
Several mass extinctions have occurred during the Earth’s history. The Cretaceous – Tertiary Boundary (K-T) Extinction caused the loss of at least three-quarters of all species known at that time including the dinosaurs. The cause of this mass extinction is a controversial subject among scientists but the fossil evidence of it’s occurrence is abundant.
effects must be global, and the effects must occur in a geologically short period of time.1
middle of paper ... ... The Web. 13 Mar. 2014. The 'Standard' of the 'Standard'. Dinosaurs: Climate Change and Biodiversity."
Throughout the various phyla discussed evolutionary advancements are relevant. Starting from the basic, simplistic life forms of a sponge, up to the intelligence of an octopus and advance organ systems of Annelida the changes have only improved. Some species changed and evolved because as populations grow, they spread out farther and different conditions begin to affect their life. Why some species haven’t changed is because their body plan and system works for the environment they inhabit. Evolution has helped animals spread out all over the world and adapt to various conditions, seen in the habitats Aschelminthes can prosper in.
It is known that in the last 650,000 years there have been seven cycles of glacial advance and retreat with the last one 7,000 years ago. This was when the modern climate era started which lead to the beginning of human civilization all