Preview

scientific theories

Good Essays
Open Document
Open Document
983 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
scientific theories
Scientific theories must have testable predictions. Predictions are made based on observations and then experiments can be done to test the theoretical predictions. The experiments will either verify or falsify the predictions made. Here we are going to discuss the hypotheses of phyletic gradualism and punctuated equilibrium. The pattern of evolution can be described as happening gradually, over time, as in the hypothesis of phyletic gradualism or by punctuated equilibrium. In the theory of punctuated equilibrium, evolution is described as happening in sudden spurts or jumps. One author describes this as the life of a soldier: “long periods of boredom interrupted by rare moments of terror” (Heylighen, 1999). Observations made using the punctuated equilibrium theory on fossils shows long intervals where nothing at all changes, this is called equilibrium. These sequences of equilibrium are punctuated by short radical transformations in which the species became extinct and was replaced by wholly new species. The accelerated rate of change in the punctuated equilibrium theory can be explained by major environmental upheavals including but not limited to changes in food supply and climate. The changes create a new direction of varieties in the species that become more favorable in the new environmental conditions (O’neil, 2011). We must think of evolution as simply change, changes in species to adapt and survive in their environments. In a stable environment, there is no selection pressure on organisms to change, so evolutionary stasis is the result. The creation and extinction of species on Earth is considered to take hundreds of millions of years to occur, based on the carbon dating process of fossils, rock formations, and erosion evidence from wind and water. These fossil observations are how scientists support evidence of evolution by gradual change. In rocks considered to be over a billion years old there is only evidence of single celled


References: Batten, D. (1994). Punctuated equilibrium: come of age? Retrieved January 20, 2012 from, http://creation.com/punctuated-equilibrium-come-of-age BioLogos Foundation, (2012). What does the fossil record show? Retrieved January 20, 2012 from, http://biologos.org/questions/fossil-record Heylighen, F. (1999). Punctuated equilibrium. Retrieved January 20, 2012 from, http://pespmc1.vub.ac.be/PUNCTUEQ.html O’neil, D. (2011). Micro and macro evolution. Retrieved January 20, 2012 from, http://anthro.palomar.edu/synthetic/synth_9.htm Riddle, M. (2007). Doesn’t carbon-14 dating disprove the Bible? Retrieved January 20, 2012 from, http://www.answersingenesis.org/articles/nab/does-c14-disprove-the-bible

You May Also Find These Documents Helpful

  • Good Essays

    5. Which theory of evolutionary change suggests that species have long periods of stability interrupted by geologically brief periods of significant change during which new species are formed? (c) Punctuated equilibrium…

    • 886 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    Bio 201 Review

    • 644 Words
    • 3 Pages

    1. The fossil record provides an incomplete chronicle of evolutionary change because the fossil records favors species that existed for a long time, were abundant and wide spread in certain kinds of environment and had hard shells.…

    • 644 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    Fossils: Today’s fossil record is much more complete than in Darwin’s time. The earliest fossil date back 3.5 billion years. Transitional forms have been found, clearly showing the path of evolution. The fossil record is not complete but t…

    • 1253 Words
    • 6 Pages
    Good Essays
  • Good Essays

    In addition to this information science uses geological and fossil records to explain the changes and diversity that have happened between species over time,through the concepts of natural selection. Scientists believe each fossil is a piece of evidence about the way species adapted and the changes that took place over a period of time.…

    • 796 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Changes in physical conditions in the environment - Some animals do not survive changes in the environment and become extinct or endangered. Changes in physical conditions such as climate ad exposure to fire has led to changes in flora (Australia drifts north)…

    • 893 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Sci101-1302b-02

    • 1172 Words
    • 5 Pages

    Evolution is and ongoing process of change and diversification which every scientist to this day accept as a historical fact. However, evolution is a very controversial subject worldwide. There are many studies, theories, and opinions regarding how we became to be, including every living creature and human being, the universe and everything else that comes along with it, and especially how our planet Earth transformed into what it is today. Phyletic gradualism and punctuated equilibrium are two very controversial and debatable theories/concepts that have brought up lots of questions, opinions, and answers. Gradualism and punctuated equilibrium are two different concepts that seem to intertwine along each other’s path. In this IP 2 I will explain both theories.…

    • 1172 Words
    • 5 Pages
    Good Essays
  • Good Essays

    By Helen Ying © 2013 Biology Notes – HSC Course 2013 MODULE 9.3 – BLUEPRINT OF LIFE 1. Outline the impact on the evolution of plants and animals of: a. Changes in physical conditions in the environment o Rising and falling sea levels – land and ice bridges across continents have affected distribution and therefore evolution when these bridges disappeared and populations were isolated from the main population. o Fossil evidence indicates mass extinctions resulting from changes in the physical environment e.g. dinosaur extinction from meteor. o Movement of continents. As Australia moved north, it became drier and plants and animals needed to adapt to these new conditions. b. Changes in chemical conditions in the environment o Original anoxic environment. As primitive organisms metabolised, carbon dioxide was released. Over millions of years, carbon dioxide accumulated and at some stage, organisms capable of using carbon dioxide in photosynthesis evolved and became dominant. Oxygen was then released as a product of photosynthesis, and oxygen-using organisms became dominant. c. Competition for resources o During the Cretaceous period, mammals were limited to the niches in which they originally evolved because the world was dominated by dinosaurs. When the dinosaurs died, the mammals were able to populate larger areas of the world as they had few competitors. As they populated these different areas, they evolved into new species to adapt to these new conditions. o Long-term competition usually results in one of the species dying out or evolution of one of the competing species so that they can occupy a different environment.  Organisms alive today have all arisen from simpler organisms that existed millions of years ago.  Evolution is the change in living organisms over many generations.  Changes in the environment of living organisms can lead to the…

    • 6173 Words
    • 25 Pages
    Good Essays
  • Powerful Essays

    Scott Hill

    • 5586 Words
    • 23 Pages

    E.G Ancient KangarooIncreased aridity led to a decrease in rainforests and an increase in open woodlands and grasslands as the Australian environment went from cool and wet to hot and dry. This change in physical environment led to the evolution of the Modern day Kangaroo from the Ancient KangarooAncient Kangaroo: small in size, generalized molarsModern Day Kangaroo: large in size, eats grasses using high crested molar teeth…

    • 5586 Words
    • 23 Pages
    Powerful Essays
  • Good Essays

    Biology Exam 2 Study guide

    • 1068 Words
    • 5 Pages

    punctuated equilibrium A concept that suggests that the tempo of evolution is more sporadic than…

    • 1068 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Study Guide

    • 1319 Words
    • 6 Pages

    * The fossils in each layer change/ evolve not just Earth time but the time frame of species…

    • 1319 Words
    • 6 Pages
    Good Essays
  • Good Essays

    Now that you have read and reviewed Chapter 1, take your learning a step further by testing your critical thinking skills on this scientific reasoning exercise.…

    • 532 Words
    • 3 Pages
    Good Essays
  • Powerful Essays

    your inner fish

    • 3496 Words
    • 11 Pages

    Through the combination of molecular and fossil data, we gain a better understanding to the concept of evolution and change.…

    • 3496 Words
    • 11 Pages
    Powerful Essays
  • Good Essays

    Over long periods of time, newer and better adapted species gradually replace older ones, which become extinct. All species are modified, creating increasingly complex and developed organisms that form new species which are connect to their ancestors through intermediate species. Darwin cannot fully explain what unfavorable conditions cause species to go extinct, but this extinction is definitely a result of the struggle for existence, as well as a necessary part of natural selection. The fiercest competition is usually between similar species, resulting in the eventual extinction of one of them, after which it is improbable that another similar species would come into existence. Darwin also argues that although natural selection does not act on ecosystems, it is possible for species around the world to change at the same time. “Parallel succession” is supported by geological evidence of similar fossils of the same period found in similar limestone formations in different places. However, later changes in these species’ behavior or environment can lead to further natural selection and formation of new species. Changes in one species can also affect changes in another. Natural selection often results in families of species that have been formed from a single parent species over time, the relationship of which can be determined through fossil records. Related…

    • 713 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Evolution is a “process over time which enables us to adapt to our changing environments”. Charles Darwin was one of the founders of this theory whereby he identified that rather that a species being fixed at creation they gradually evolve from that of their common ancestors (Darwin cited in Clegg 2007) with characteristics and behaviours, that best suit the ever changing environment we live in, being passed down the generations in order to support survival.…

    • 1774 Words
    • 8 Pages
    Good Essays
  • Good Essays

    Evolution is basically the change in the heritable characteristic or traits in living organisms which are passed from one generation to another and gives rise to diversity at every stage of the organism’s biological organisation. The process of evolution was not well understood until 19th century when Charles Darwin proposed the scientific theory of natural selection as a driving tool in evolution. The process involved both the macroevolution in which organisms went through major evolutionary changes over a long period of time and acquired different traits from different parents or ancestries and the microevolution in which a group of organisms went through minimal changes with time but the traits they acquired were typically from the same ancestor.…

    • 630 Words
    • 3 Pages
    Good Essays