...ology Chapter 13 Lecture Outline Introduction Clown, Fool, or Simply Well Adapted? A. Review: Evolution is the central theme of biology. Evolutionary adaptation is a universal characteristic of living things (see Module 1.6). NOTE: More than any other idea in biology, evolutionary theory serves to tie the discipline together. T. Dobzhansky: “Nothing in biology makes sense except in the light of evolution.” B. If you look at any organism critically, you are first struck by the differences from other organisms. 1. Further observation often reveals that an organism’s features show some relationship to where the organism lives and what it does in its environment. 2. The blue-footed booby has enormous webbed feet, an oil producing gland that keeps the booby afloat, a nostril that can close under water that prevents water from entering the lungs, a gland that secrets salt from consumed sea water, and a torpedo-like body—all adaptations that make life on the sea feasible. I. Darwin’s Theory of Evolution Module 13.1 A sea voyage helped Darwin frame his theory of evolution. A. Awareness of each organism’s adaptations and how they fit the particular conditions of its environment helps us appreciate the natural world (Figure 13.1A). B. Early Greek philosophers held various views. Anaximander (about 2,500 years ago) suggested that life arose in water and that simpler forms...
Words: 3614 - Pages: 15
...Evidence of Evolution Introduction: Evolution is usually defined as the change over time in one or more inherited traits found in populations of organisms. Inherited traits are particular distinguishing characteristics. Evolution may occur when there is variation of inherited traits within a population. The major sources of such variation are mutation, genetic recombination and gene flow. This process has produced all the diversity of living organisms. Charles Darwin characterized the result as endless forms most beautiful and most wonderful. It has always been debated if there is any evidence of evolution and in what fields, in this report we will give a brief summary concerning: • DNA Evidence of Evolution • Biological Evidence of Evolution DNA Evidence of Evolution: DNA molecules are complex molecules which contain the assembly instructions for every living creature. Certain aspects of DNA have been interpreted as evidence for Darwinian evolution. DNA evidence for evolution includes mutations, genetic similarities among species, so-called “Junk DNA” and “Pseudogenes.” The fact that mutations can corrupt DNA is important for the Darwinian paradigm because in order for an organism to eventually evolve into an entirely different organism, changes must be made to the creature’s genome over time. But Darwinian evolution needs more than just change. It needs an increase in genetic information. Critics point out that genetic mutation does not appear to provide a...
Words: 1011 - Pages: 5
...submission Garbology Introduction Evolution is a very interesting concept in anthropology. It refers to the biological populations’ alteration of the inherited characteristics over successive generations. The processes in evolution bring diversity at each biological organization level including, individual organisms, molecules like proteins and DNA, and species. According to what we know, life on this universe actually originated and afterwards evolved from universal common ancestor. Perhaps this is what makes the subject of evolution appear more interesting since through it we get well informed about where we originated from and about our evolution. The concept of evolution is basically categorized under both micro and macroevolution processes. Microevolution refers to changes in the allele frequencies which occur overtime within a given population. For that reason, microevolution refers to the smaller evolutionary changes. For that reason, microevolution is gene pool changes of a population over a certain period of time that result in fairly small changes to organisms found in the population. A good example of such changes includes species’ size or coloring change. This change is essentially as a result of the four processes which in this case are mutation, gene flow, genetic drift, and selection both artificial and natural. Mutation is actually a nucleotide sequence change of an organism genome, extra chromosomal genetic element, or virus. These processes come...
Words: 624 - Pages: 3
...the ability to evolve is a ubiquitous property of living organisms. More specifically, it is the capacity to generate heritable, non-lethal phenotypic variation. Biologists have long recognized that evolvability of developmental programs in animals is key to their complex morphological architecture. However there is an increasing need to synthesize known facts about the developmental phenomena into mechanistic descriptions of complex systems. This ambition demands the need to understand the underlying determinants of evolvable developmental systems. I aim to review the dynamics of two systems-level phenomena: modularity and robustness and their evolutionary implications. Despite a plethora of literature, these terms have remained very ambiguous. Modularity reduces interdependence of components and confers robustness. Robustness, which is broadly understood, as the insensitivity of a biological systems functionalities to perturbations is another design principle in itself. Such robustness could enhance the potential for future evolutionary innovations. Both these properties therefore affect evolvability of a lineage. In this essay I aim to articulate my way through this hierarchy of modularity, robustness and evolvability, elucidating mechanisms that reveal their interplay to maximize functionality. I further discuss whether evolution of evolvability itself is possible. 1 Acknowledgements Firstly, I would like to sincerely thank my supervisor, Professor Armand Leroi for his...
Words: 8370 - Pages: 34
...*Q: What is Evolution? - Descent from modification * Macro Evolution (Large Scale Evolution) * Common Ancestor - descent of different species over many generations * OVER LARGER TIMESCALE (ex. Speciation) * Micro Evolution (Small Scale Evolution) * Changes in gene (allele) frequency in population from one generation to the next * May be over shorter time period (generations) * BOTH OF THESE IMPLY: * 1. Common Ancestry * 2. Changes through time *Natural selection occurs when 3 conditions are met; results in evolution * 1. There is variation in a trait * (Ex. Beetle color) * 2. The trait is heritable * (Ex. Brown beetles tends to have brown babies) * 3. There is differential reproductive success, and not all individuals reproduce to their full potential * (Ex. Green beetles are selected against by natural and Brown beetles are selected for- so they reproduce more) *Adaption: A trait that increases the ability of an individual to survive and reproduce compared with individuals without the trait Adaption in an evolutionary context: An inherited trait that makes an organism more fit in its abiotic and biotic environment, and that has arisen as a result of the direct action of natural selection for its primary function. Ex. Mimicry of the non-toxic king snake to evade predators Natural selection leads to Adaptions * Adjustments or changes In behavior, physiology...
Words: 4620 - Pages: 19
...What is evolution? Providing a definition of “evolution” is tricky because the word is used in different ways. First we need to distinguish between the broader worldview some associate with evolution and the scientific theory of evolution. The theory of evolution by natural selection, first formulated in Charles Darwin's book "On the Origin of Species" in 1859, is the process by which organisms change over time as a result of changes in heritable physical or behavioral traits. Changes that allow an organism to better adapt to its environment will help it survive and have more offspring. The theory of evolution is based on the idea that all species are related and gradually change over time. Evolution relies on there being genetic variation in a population which affects the physical characteristics (phenotype) of an organism. Some of these characteristics may give the individual an advantage over other individuals which they can then pass on to their offspring. Evolution by natural selection is one of the best substantiated theories in the history of science, supported by evidence from a wide variety of scientific disciplines, including paleontology, geology, genetics and...
Words: 1685 - Pages: 7
...The Theory of Evolution by: Riley Buenaventura The theory of evolution incorporates a logical view that natural life on our planet has changed over time and continues to change by a process known as "natural selection". Charles Darwin, a nineteenth century naturalist, is given credit for this hypothesis, not just because he was the first person to suggest that evolution occurs. Natural selection is where organisms that are most best suited to their habitat or surroundings, survive and pass on their hereditary attributes for future generations. Charles Darwin “It is not the strongest of the species that survive, nor the most intelligent, but the one most responsive to change.” Therefore, the fittest survive and multiply. Natural...
Words: 719 - Pages: 3
...What is Anthropology??? • • • 20:41 Anthropology • Scientific Approach, OBJECTIVE • Study of Humankind- human groups • Seeks to produce useful GENERALIZATIONS about people and their BEHAVIORS • To arrive at an UNBIASED UNDERSTANDING OF HUMAN DIVERSITY • Only scientific discipline that attempts to embrace an understanding of all of humanity • Helps us understand ourselves an others Anthropology Perspectives • Holistic Approach (broadest view) o To view things in the broadest possible contest o To cover the whole scope of humanity o To provide a total or composite view o Human culture as a system, functional whole, all parts relate o Biocultural Perspective Studies both the PHYSICAL and SOCIAL EX: kuru disease (neurological disease)- disease caused by culture, transmitted by mortuary practices • Cultural Relativism o To view the beliefs and customs of other peoples within the context of their culture not one’s own o Practice of not judging other cultures based on the standards of one’s own culture o ENDOCENTRISM Group centeredness Tendency to see ones own culture as the center of everything The measure or standard against which all other lifeways are evaluated Tendency to consider ones own culture as superior or better than all others o Anthropologists must be unbiased, objective o Involves an effort to remain unbiased in ones observations o Acknowledges that cultures are DIFFERENT, but NOT RANKED o No right or wrong cultures...
Words: 4747 - Pages: 19
...A. Examine the mechanisms of evolution. * Evolution is the process by which modern organisms have descended from ancient ancestors (Evolution, N.D.) The four mechanisms that allow evolution to take place are genetic drift, gene flow, mutations, and natural selection. All of these mechanisms happen naturally and are necessary for evolution to take place. Genetic drift is the random change in gene or allele frequency with which an allele variation occurs in a small population. Genetic drift is simple change. Two different genetic drifts that can change the size of a population are the bottleneck effect and the founder effect (Campbell, Reece and Simon, 2004). The bottleneck effect occurs during drastic changes in an alleles population causing the population to have some alleles that may be underrepresented or eliminated completely (Campbell, Reece and Simon, 2004). Chance may affect the alleles population for generations until the population will become large enough to allow sampling errors to be considered insignificant (Campbell, Reece and Simon, 2004). Genetic drift in a new colony is called the founder effect (Campbell, Reece and Simon, 2004). It is likely to occur when a few individuals colonize an isolated area (Campbell, Reece and Simon, 2004). When a colony migrates away from a larger population its gene pool becomes least representative of the larger colony it migrated from (Campbell, Reece and Simon, 2004). Gene flow is the genetic exchange of another population...
Words: 661 - Pages: 3
...and Evolution, University of Chicago, Chicago, Illinois, United States of America, 3 Ben May Department for Cancer Research, University of Chicago, Chicago, Illinois, United States of America Summary: Recent cancer studies emphasize that genetic and heritable epigenetic changes drive the evolutionary rate of cancer progression and drug resistance. We discuss the ways in which nonheritable aspects of cellular variability may significantly increase evolutionary rate. Nonheritable variability arises by stochastic fluctuations in cells and by physiological responses of cells to the environment. New approaches to drug design may be required to control nonheritable variability and the evolution of resistance to chemotherapy. Cancer progression is a series of evolutionary changes. Those changes include enhanced cellular proliferation, reduced cellular death by abrogating normal apoptotic mechanisms, greater invasiveness by increased expression of proteases, and improved colonizing ability to achieve metastasis [1]. In response to drug treatment, cancer cells often evolve resistance and continue to spread. Each evolutionary step typically proceeds by acquisition of genetic or heritable epigenetic changes in cells. When does the novel genetic change arise in an evolutionary step? By the current view, rare genetic variants arise before widespread phenotypic change. The idea is that a novel phenotype always comes from a novel genotype [2,3]. For example, rare resistant genetic variants...
Words: 7532 - Pages: 31
...brightly colored individuals and eliminating them from the gene pool. Therefore, guppy populations are evolving to more closely match, or stand out from their environment. Endler hypothesized that intense predation caused natural selection in male guppies, favoring the trait of drab coloration. He further tested his hypothesis by transferring brightly colors guppies to a pool with many predators. As he predicted, over time the transplanted guppy population became less brightly colored. Females tend to look for the bright colored male guppies in the pool and mate with them. This enables those males to have a higher probability of passing their genes on to their next generation. In the simulation, predators can dramatically influence the evolution of a population of guppies, but change does not occur quickly during the testing of one generation for each trial. (Before columns on graphs in...
Words: 2402 - Pages: 10
...DNA in Forensic Science DNA is the carrier of genetic information in humans and other living organisms. It has become a very useful tool in forensic science since it was discovered. In forensic science, DNA testing is used to compare the genetic structure of two individuals to establish whether there is a genetic relationship between them. One example of the use of DNA in forensic science that is important in biology today is comparing a suspect’s DNA profile to DNA that was discovered at a crime scene. This can be done by DNA fingerprinting or by collection of body fluids, such as saliva, semen, urine, blood, skin and hair, found at the scene. Secondly, DNA testing can rule out possible suspects as well. DNA testing can be used to free individuals...
Words: 1116 - Pages: 5
...body constant. Maintenance = Homeostasis Maintenance Physiology How is homeostasis maintained? Control theory: A control center senses when an physiological condition is out of balance and stimulates an effector organ to return the condition to the normal, optimal level. Homeostasis: Recap Why maintain homeostasis? To preserve physiological function, in order to increase survivorship, in order to increase reproductive fitness… Evolution Shapes Physiology • Evolution is itself a process that allows populations of organisms to adapt to their environments. Evolution and Genetics • Evolution is defined as: changes in allele frequencies of a population over time • Any physiological or morphological changes not represented in germ cell genes will not contribute to evolution Genetic variation Due to random mutations, differences exist in the genetic code (genome) between the individuals of any given species. This is called genetic variation. For a given allele, particular genetic...
Words: 987 - Pages: 4
...Evolution Abstract One paragraph… The discussion on the origin and fate of the universe continues to revolve around creationists and evolutionary ideas, though creationism positions arise mainly of religion and philosophy, while the evolution is postulated mainly from science. One wonders if possible convergence in these fields in the discussion, that is, if you can address both creationism and evolutionism from science, philosophy and religion. Theory of Evolution In science the theory of evolution explains the huge variety of life arising by postulating a process of transformation through changes in genes that lead to new adaptations to the environment. By studying the genetic structure of living beings is a verifiable fact that they are related to each other and, therefore, aims to have a common origin as the emergence of new species due to the accumulation of changes that do diverge and take different paths to adaptation to the environment. In the scientific world, biological evolution represents the interpretative key of the living world. Life began about 3500 makes 4000 million years in the form of single-celled organisms without nuclei and took about two billion years to produce the first eukaryotes (unicellular organisms with nuclei), so the start was given very slowly. However, in evolutionary history there are times with a high evolutionary rate as the Cambrian period (540 to 520 million years, they were many forms of multicellular life). They also appeared...
Words: 2014 - Pages: 9
...Evolution All humans have one thing in common, their ancestry. Evolution is a theory that explains the genetic diversity in all living organisms. For example, it explains how humans evolved from apes (“Academy defends teaching evolution”). The theory of evolution is largely based on the ideas of Charles Darwin and is controversial because it contradicts current theories on creation (“Human Evolution”). Charles Darwin is credited for the beginning of the theory of evolution (look in cites). The reason most scientist agree with the theory is because it is backed by facts (“Human Evolution”). Evolution is the journey that can be proven through genetics, anatomy, and geology. Charles Darwin’s research shown in his book, On the Origins of Species by Natural Selection, gave birth to the theory of evolution (“Human Evolution”). Darwin, during his research noticed the variation through heredity in all living organisms in nature (cite). Explained in his book On the Origins of species by Natural Selection, “these individual differences are highly important for us, as they afford materials for natural selection to accumulate” (Darwin and Levine 47). He also explains that evolution, through natural selection, only helps each organism to become better...
Words: 1202 - Pages: 5
