General Biology II Q1M4.1 Evidence of Evolution PDF

Senior High School General Biology II Quarter 1 – Module 4.1 Evidence of Evolution  COPYRIGHT 2020 Section 9 of the Presidential Decree No. 49 provides: “No copy shall subsist in any work of the Govern...

Senior High School General Biology II Quarter 1 – Module 4.1 Evidence of Evolution  COPYRIGHT 2020 Section 9 of the Presidential Decree No. 49 provides: “No copy shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit.” The original version of this material has been developed in the Schools Division of Surigao del Norte through the Learning Resource Management and Development Section of the Curriculum Implementation Division. This material can be reproduced for educational purposes; modified for the purpose of translation into another language; and creating of an edited version and enhancement of work are permitted, provided all original work of the author and illustrator must be acknowledged and the copyright must be attributed. No work may be derived from any part of this material for commercial purposes and profit. This material has been approved and published for online distribution through the Learning Resource Management and Development System (LRMDS) Portal (http://lrmds.deped.gov.ph) and Division Network Academy (https://netacadsdn.com). Development Team of the Module Writer: Ennocent John G. Comandante Editors: Nanette B. Bonostro, Magnolia L. Molina, Eliza B. Escabal, Felisa B.Cordova Reviewers: Gersim S. Lumintac, Gregorio T. Llano Jr., Elena M. Navallo Illustrators: Danilo L. Galve, Stephen B. Gorgonio, Melchor O. Rivera Layout Artists: Ivan Paul V. Damalerio, Alberto S. Elcullada, Jr. Management Team: Ma. Teresa M. Real Laila F. Danaque Dominico P. Larong, Jr. Gemma C. Pullos Manuel L. Limjoco, Jr. Printed in the Philippines by Department of Education – Schools Division of Surigao del Norte Office Address: Peñaranda St., Surigao City Tel. No.: (086) 826-8216 E-mail Address: [email protected]  Senior High School General Biology II Quarter 1 – Module 4.1 Evidence of Evolution ii Introductory Message For the facilitator: Welcome to the General Biology II 12 Self-Learning Module on Evidence of Evolution. This module was collaboratively designed, developed and reviewed by educators both from public and private institutions to assist you, the teacher or facilitator in helping the learners meet the standards set by the K to 12 Curriculum while overcoming their personal, social, and economic constraints in schooling. This learning resource hopes to engage the learners into guided and independent learning activities at their own pace and time. Furthermore, this also aims to help learners acquire the needed 21st century skills while taking into consideration their needs and circumstances. In addition to the material in the main text, you will also see this box in the body of the module: Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners. As a facilitator, you are expected to orient the learners on how to use this module. You also need to keep track of the learners' progress while allowing them to manage their own learning. Furthermore, you are expected to encourage and assist the learners as they do the tasks included in the module. For the learner: Welcome to the General Biology II 12 Self-Learning Module on Evidence of Evolution. This module was designed to provide you with fun and meaningful opportunities for guided and independent learning at your own pace and time. You will be enabled to process the contents of the learning resource while being an active learner. ii This module has the following parts: Activity : This will bring understanding to what you already know and experience to what you should learn further. Analysis : In this phase, you will process and classify what is valid and not for a more in-depth understanding. Abstraction : This part leads you in reinforcing what you know and should know more. Exercises are presented for independent practice to solidify your understanding and skills of the topic. Application : This stage brings you to a more practical way that you are going to use what you have learned and think new ways on how it can be improved further. iii  CONTENTS OF THE MODULE Page Content Standard 1 Performance Standard 1 Learning Competency 1 Learning Objectives 1 DAILY LEARNING TASK: Day Learning Task 1 Introduction 1-8 Pre-Test Review of the Previous Module Presentation of the Module Activity 2 Analysis 8-20 Abstraction Application 3 Reflect 21-22 Learn More References 23 1 CONTENT STANDARD The learners demonstrate an understanding of Relevance, Mechanisms, Evidence/Bases, and Theories of Evolution. PERFORMANCE STANDARD The learners should be able to state differences of homologous and analogous structure by using table and diagram. LEARNING COMPETENCY The learners should be able to explain the evidences of evolution (STEM_BIO11/12-IIIc-g-12) LEARNING OBJECTIVES: At the end of the module, you should be able to: 1. explain the development of the theory of evolution; 2. understand how evolution is being studied from the fossil record to molecular data; and 3. give and value the importance of understanding the origin of life. INTRODUCTION Man's inquisitive nature compels him to ask questions and produce proof. An organism can only be named if there is foolproof documentation of its actual existence. Since Darwin's time, we have been searching for and have been analyzing evidence in nature to educate us more about evolution. Some types of evidence used by Darwin, such as fossils and similarities between related living organisms, are still being used today. Other examinations such as DNA testing, that were not available during that time, are being used by scientists today to validate the existence of evolution. This self-guided module is focused on understudies in the 'new normal' instructive setting as endorsed by the Department of Education that advances autonomous learning of the objective topics, ideas, and abilities that will build up your genuine based aptitudes. It is moored on the overall standards, objectives, and destinations of the K to 12 Basic Education program for Grade 12 that will empower you to become a self-realizing, beneficial and compelling member of the general public and the world on the loose 1 PRE-TEST Directions: Read each item carefully and identify what is asked or described. Encircle the letter of the correct answer. 1. Which of the following describe evolution? A. Evolution is continuous. B. Evolution refers to change. C. The world is stable and unchanging. D. If there is mutation, there is evolution. 2. Where can most of the fossils be found? A. Sedimentary rocks B. Granite rocks C. Lava flows D. Black soil 3. In what Era can the oldest fossils be found? A. Cenozoic B. Mesozoic C. Paleozoic D. Pre-Cambrian 4. Which is more definite characteristics to show relatedness of two organisms? A. Similarity in structure B. Similarity in development C. Similarity in genomic DNA D. Similarity in courting behavior 5. Scientific evidence shows that modern dogs, wolves, and foxes all have a common ancestor. Further evidence shows that dogs are more closely related to wolves than to foxes. Which of the following observations provides the best evidence that dogs are more closely related to wolves than to foxes? A. The diets of dogs and wolves are more similar than the diets of dogs and foxes. B. The lifespans of dogs and wolves are more similar than the lifespans of dogs and foxes. C. The genetic sequences of dogs and wolves are more similar than the genetic sequences of dogs and foxes. D. The body sizes of dogs and wolves are more similar than the body sizes of dogs and foxes. 2 6. Whale fins and bat wings are anatomically similar. Which of the following does this suggest about the animals? A. Whales and bats move in the same way. B. Whales and bats have a common ancestry. C. Whales and bats have existed for the same amount of time. D. Whales and bats were once adapted to the same environment. 7. Which of the following is the best scientific evidence that mammals evolved from reptiles? A. similarities in the diets of extinct reptiles and modern mammals B. similarities in the average lifespans of modern reptiles and modern mammals C. fossils of ancient reptiles and mammals that appear together in the same layers of rock D. fossils that show gradual changes in skull shape from reptile-like organisms to mammal-like organisms. 8. When body structures of two different organisms have similar form, they are said to be _______. A. analogous B. homologous C. homozygous D. similar 9. By comparing the amino acid sequences of chimpanzees, orangutans, and humans, a scientist is said to be looking for evidence of evolution by means of what? A. molecular biology B. comparative biochemistry C. comparative embryology D. cytochrome analysis 10. Which of the following is an example of anatomical evidence for evolution? A. The DNA of two related species. B. Amber preserved or frozen fossils C. Vestigial structures D. All of the above 11. The wings of a butterfly and the wings of a bat are said to be analogous structures because A. butterflies and bats share a common ancestor B. butterflies and bats are unrelated C. both structures serve the same function D. both structures are similar in their form. 3 12. Why do organisms with close biochemical similarities show stronger evolutionary relationships? A. They have varied and different ancestry. B. They have similar patterns during their early stages of development. C. They have a common ancestor and have the same kind of proteins. D. They possess same vestigial structure that made their evolutionary relationship closer. 13. Vertebrate embryos resemble each other during early development. For example, fish, turtles, chickens, mice and humans all go through a stage where they have tails and gill slits. This suggests that____. A. Early embryonic development doesn't change much. B. Ancestral vertebrates had genes causing the development of tails and gill slits, and their descendants still retain those genes. C. Genes which change the developmental pathways in vertebrates arose later in evolution. D. All of the above. 14. A biologist analyzes the DNA sequences of 3 different primates. She finds that primates A and B have almost exactly the same DNA sequences, whose those of primate C are different in several places. She would most likely infer A. primates A and B are more closely related to one another than either is to primate C B. all 3 primates appeared on Earth at the same time C. either primate A or primate B must be a direct ancestor of primate D. primate C must have been the ancestor of both A and B. 15. What is the most likely effect of killing 80% of a colony of bacteria with a certain antibiotic? A. The remaining bacteria will re-grow into a new colony more resistant to the antibiotic B. The remaining bacteria will die because of the drastic decimation C. The bacteria will not cause any further infections because their numbers have been drastically reduced D. The bacteria will try to start a new colony where the antibiotic will not be found “Congratulations you made it! 4 REVIEW OF THE PREVIOUS MODULE Directions: You should be able to write out the definitions of each of the following terms in your own words: 1. geology- 2. fauna and flora- 3. population- 4. fossil- 5. adaptation- 6. stratum (sing.), strata (pl.)- 7. descent with modification- 8. naturalist- 9. natural selection- 10. artificial selection- 5 PRESENTATION OF THE NEW MODULE The evidence for evolution is compelling and extensive. Looking at every level of organization in the living systems, biologists see the signature of the past and present evolution. Darwin dedicated a large portion of his book, "On the Origin of Species,” identifying patterns in nature that were consistent with evolution and since Darwin, our understanding has become clearer and broader. Organisms inhabiting the earth have changed over time, their structures, traits, and abilities allowed them to adapt and survive in their environment. Data from the fossil records, anatomy, and morphology, embryonic development, and biochemistry could be analyzed to demonstrate if the evolution of life on earth has taken place. In this module, you will figure out how evolution presented new notions for us to fully understand that maintaining individual differences and a variety of characteristics are important to ensure the survival of species. This also discusses the different sources of possible evidence for evolution such as fossil records, and developmental and molecular biology which gave way to the different concepts about the origin of life. 6 ACTIVITY 1 “FOSSIL: Rehome!” Directions: Try to place or draw the fossils of the following organisms in the Era and period where they belong. Trilobites Dinosaur Bone Humans First fishes First birds Neuropteris Ammonite First Amphibians First Reptiles Crinoid Stem First primates Mammoth Hoofed Mammals Geologic Time Scale, 650 million years ago to present ERA PERIOD ORGANISM CENOZOIC Recent Quaternary Tertiary MESOZOIC Cretaceous Jurassic Triassic PALEOZOIC Permian Carboniferous Devonian Silurian Ordovician Cambrian “I know you can do it. Now it’s time for you to EXPLORE the mystery behind those words. You’re doing great!” 7 ANALYSIS “Let Us Talk the Past!” Directions: Answer the following questions based on the activity you just answered. 1. Analyze the table above. Which is assumed to be the oldest organism? Why do you think so? What is the probable age of the fossil? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 2. In what era can you possibly find the most recent fossil? Why do you say so? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 3. Do you think some organisms lived during the Cambrian Period? Explain your answer. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 4. When do you think did present-day humans first appeared on earth? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 5. Describe how organisms are arranged in the table. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 8 ACTIVITY 2 “Not the same? No problem!” Directions: Write in the space provided H if the structure below is homologous and A if they are analogous. Structures Classification Butterfly wing Bat wing 9 Directions: Answer the following questions based on the activity you just answered. 1. Can you say that humans, whales, and bat might belong to a common ancestral group? Explain why. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ 2. Give other examples of homologous and analogous structures. homologous analogous ACTIVITY 3 “How close!” Directions: Study and compare the stages of embryonic development of the different vertebrates. Source: https://www.biology-pages.info/R/Recapitulation.html 10 Guide Questions: Directions: Answer the following questions based on the activity you just study and compared. 1. In what stages of development of the organisms above show similarities? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 2. Identify the structure, how and where are they similar? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 3. Can embryonic development be evidence that evolution took place? Explain. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ Good job! I told you, you can do better! It is time to know it all. Read on. ABSTRACTION Evidence of Evolution: Overview Darwin and other 19th-century scientists found compelling prove for natural advancement within the comparative consider of living life forms, in their geographic dispersion, and within the fossil remains of terminated life forms. Since Darwin's time, the prove from these sources has ended up significantly more grounded and more comprehensive, whereas natural disciplines that developed more recently— genetics, organic chemistry, physiology, biology, creature conduct (ethology), and particularly atomic biology—have provided effective extra prove and point by point affirmation. The amount of data around developmental history put away within the DNA and proteins of living things is essentially boundless; researchers can reproduce any detail of the developmental history of life by contributing adequate time and research facility assets. Evolutionists not are concerned with getting prove to back the reality of advancement but or maybe are concerned with what sorts of information can be gotten from diverse sources of proving. The following areas recognize the foremost profitable of these sources and outline the sorts of data they have given. 11 THE FOSSIL RECORD Paleontologists have recouped and considered the fossil remains of numerous thousands of life forms that lived within the past. This fossil record appears that numerous sorts of terminated life forms were exceptionally distinctive in shape from any presently living. It too appears progressions of life forms through time, showing their move from one frame to another. When a life form kicks the bucket, it is as a rule devastated by other shapes of life and by weathering forms. On uncommon events, a few body parts—particularly difficult ones such as shells, teeth, or bones—are protected by being buried in mud or secured in a few other ways from predators and climate. In the long run, they may end up petrified and protected uncertainly with the rocks in which they are implanted. Strategies such as radiometric dating—measuring the sums of characteristic radioactive molecules that stay in certain minerals to decide the slipped by time since they were constituted— make it possible to estimate the time when the rocks, and the fossils associated with them, were formed. Radiometric dating shows that Earth was shaped almost 4.5 billion a long time prior. The most punctual fossils take after microorganisms such as microscopic organisms and cyanobacteria (blue-green green growth); the most seasoned of these fossils show up in rocks 3.5 billion a long time ancient. The most seasoned known creature fossils, around 700 million a long time ancient, come from the so- called Ediacaran fauna, little wormlike animals with delicate bodies. Various fossils having a place to numerous living phyla and showing mineralized skeletons show up in rocks around 540 million a long time ancient. These living beings are distinctive from living beings living presently and from those living at interceding times. A few are so profoundly distinctive that paleontologists have made modern phyla in arrange to classify them. The primary vertebrates, creatures with spines, showed up around 400 million a long time back; the primary well evolved creatures, less than 200 million a long time prior. The history of life recorded by fossils presents compelling proof of advancement. The fossil record is fragmented. Of the little extent of life forms protected as fossils, as it were a modest division have been recouped and examined by paleontologists. In a few cases, the progression of shapes over time has been reproduced in detail. One case is the advancement of the horse. The horse can be followed to a creature the measure of a canine having a few toes on each foot and teeth suitable for browsing; this creature called the first light horse (sort Hyracotherium), lived more than 50 million a long time prior. The foremost later shape, the advanced horse (Equus), is much bigger in a measure, is one-toed, and has teeth suitable for brushing. The transitional shapes are well protected as fossils, as are numerous other sorts of extinct horses that advanced completely different bearings and cleared out no living relatives. 12  Utilizing recouped fossils, paleontologists have recreated cases of radical developmental moves in frame and work. For case, the lower jaw of reptiles contains a few bones, but that of warm-blooded animals as it were one. The other bones within the reptile jaw unmistakably advanced into bones presently found within the mammalian ear. To begin with, such a move would appear unlikely—it is difficult to assume what work such bones may have had amid their halfway stages. However paleontologists found two transitional shapes of mammal-like reptiles, called therapsids, that had a twofold jaw joint (i.e., two hinge focuses side by side)—one joint comprising of the bones that continue within the mammalian jaw and the other composed of the quadrate and articular bones, which in the long run got to be the pound and iron block of the mammalian ear. For doubtful counterparts of Darwin, the “missing link”—the nonattendance of any known transitional shape between primates and humans—was a fight cry, because it remained for ignorant individuals a while later. Not one but numerous animals middle between living gorillas and people have since been found as fossils. The most seasoned known fossil hominins—i.e., primates having a place to the human heredity after it separated from heredities reaching to the apes—are 6 million to 7 million a long time ancient, come from Africa, and are known as Sahelanthropus and Orrorin (or Praeanthropus), which were overwhelmingly bipedal when on the ground but which had exceptionally little brains. Ardipithecus lived almost 4.4 million a long time back, moreover in Africa. Various fossil remains from assorted African roots are known of Australopithecus, a hominin that showed up between 3 million and 4 million a long time prior. Australopithecus had an upright human position but a cranial capacity of less than 500 cc (comparable to a brain weight of around 500 grams), comparable to that of a gorilla or a chimpanzee and about one-third that of humans. Its head displayed a mixture of ape and human characteristics—a low forehead and a long, apelike face but with teeth proportioned like those of humans. Evolution of the horse 13  Other early hominins somewhat contemporaneous with Australopithecus incorporate Kenyanthropus and Paranthropus; both had comparatively little brains, in spite of the fact that a few species of Paranthropus had bigger bodies. Paranthropus speaks to a side department within the hominin lineage that became terminated. At the side expanded cranial capacity, other human characteristics have been found in Homo habilis, which lived around 1.5 million to 2 million a long time prior in Africa and had a cranial capacity of more than 600 cc (brain weight of 600 grams), and in H. erectus, which lived between 0.5 million and more than 1.5 million a long time back, clearly extended broadly over Africa, Asia, and Europe, and had a cranial capacity of 800 to 1,100 cc (brain weight of 800 to 1,100 grams). The brain sizes of H. ergaster, H. antecessor, and H. heidelbergensis were generally that of the brain of H. erectus, a few of which species were somewhat contemporaneous, in spite of the fact that they lived in numerous districts of the Eastern Half of the globe. Human lineage. Five hominins—members of the human lineage after it separated at least seven million to six million years ago from lineages going to the apes—are depicted in an artist's interpretation. All but Homo sapiens, the species that comprise modern humans, are extinct and have been reconstructed from fossil evidence. Source: Encyclopædia Britannica, Inc. STRUCTURAL SIMILARITIES The skeletons of turtles, steeds, people, feathered creatures, and bats are strikingly comparative, in show disdain toward the diverse ways of life of these creatures and the differences of their situations. The correspondence, bone by bone, can effortlessly be seen not as it were within the appendages but too in each other 14 portion of the body. From a simple down to earth point of view, it is unimaginable that a turtle ought to swim, a horse run, an individual write, and a feathered creature or a bat fly with forelimb structures built of the same bones. A design may plan way better appendages in each case. But on the off chance that it is acknowledged that all of these skeletons acquired their structures from a common predecessor and got to be adjusted as it were as they adjusted to diverse ways of life, the closeness of their structures makes sense. Homologies of vertebrate forelimbs. Homologies of the forelimb among vertebrates, giving evidence for evolution. The bones correspond, although they are adapted to the specific mode of life of the animal. (Some anatomists interpret the digits in the bird's wing as being 1, 2, and 3 rather than 2, 3, and 4.) Encyclopædia Britannica, Inc. Comparative life systems examine the homologies, or acquired similitudes, among life forms in bone structure and other parts of the body. The correspondence of structures is ordinarily exceptionally near among a few organisms—the diverse assortments of warblers, for instance—but gets to be less so as the living beings being compared are less closely related in their developmental history. The similitudes are less between warm-blooded animals and feathered creatures than they are among warm-blooded creatures, and they are still less between warm- blooded creatures and angles. Similitudes in structure, in this manner, not as it were show advancement but to offer assistance to recreate the phylogeny, or developmental history, of living beings. Comparative life structures uncover why most organismic structures are not idealized. Just like the forelimbs of turtles, steeds, people, fowls, and bats, an organism's body parts are less than flawlessly adjusted since they are modified from an acquired structure instead of outlined from totally "raw" materials for a particular 15 reason. The blemish of structures is proving for advancement and against antievolutionist contentions that conjure brilliantly plan. EMBRYONIC DEVELOPMENT AND VESTIGES Darwin and his adherents found bolster for advancement within the consider of embryology, the science that explores the advancement of life forms from fertilized egg to time of birth or brings forth. Vertebrates, from angles through reptiles to people, create in ways that are astoundingly comparable amid early stages, but they ended up increasingly separated as the embryos approach development. The similitudes endure longer between living beings that are more closely related (e.g., people and monkeys) than between those less closely related (people and sharks). Common formative designs reflect developmental connection. Reptiles and people share a formative design acquired from their inaccessible common precursor; the acquired design of each was adjusted as it were as the separate descendant ancestries advanced completely different bearings. The common embryonic stages of the two animals reflect the limitations forced by this common legacy, which avoids changes that have not been required by their diverging environments and ways of life. The embryos of humans and other nonaquatic vertebrates display gill openings even in spite of the fact that they never breathe through gills. These openings are found within the embryos of all vertebrates since they share as common predecessors the angle in which these structures to begin with advanced. Human embryos moreover show by the fourth week of advancement a well-defined tail, which comes to most extreme length at six weeks. Comparative embryonic tails are found in other warm-blooded creatures, such as pooches, steeds, and monkeys; in people, be that as it may, the tail, in the long run, abbreviates, continuing only as a rudiment within the grown-up coccyx. A near developmental relationship between life forms that show up radically distinctive as adults can in some cases be recognized by their embryonic homologies. Barnacles, for example, are stationary shellfish with a small clear resemblance to such free-swimming shellfish as lobsters, shrimps, or copepods. However, barnacles pass through a free-swimming larval stage, the nauplius, which is unmistakably comparative to that of other shellfish hatchlings. Embryonic rudiments that never completely develop, such as the gill slits in humans, are common in all sorts of creatures. A few, in any case, just like the tail rudiment in humans, hold on as adult vestiges, reflecting developmental family line. The foremost commonplace simple organ in people is the vermiform reference section. This wormlike structure connects to a brief area of the digestive system called the cecum, which is found at the point where the large and small insides connect. The human vermiform reference section may be a functionless remnant of 16 a completely created organ show in other well evolved creatures, such as the rabbit and other herbivores, where an expansive cecum and reference section store vegetable cellulose to empower its assimilation with the assistance of microscopic organisms. Remnants are occasions of imperfections—like the defects seen in anatomical structures—that contend against creation by plan but are completely justifiable as a result of advancement. Darwin moreover saw an affirmation of advancement within the geographic dissemination of plants and creatures, and afterward, information has fortified his perceptions. For example, there are around 1,500 known species of Drosophila vinegar flies within the world; about one-third of them live in Hawaii and no place else, in spite of the fact that the whole zone of the archipelago is less than one- twentieth the region of California or Germany. Too in Hawaii are more than 1,000 species of snails and other arrive mollusks that exist no place else. These unordinary differences are effectively clarified by advancement. The islands of Hawaii are amazingly separated and have had few colonizers—i.e, creatures, and plants that arrived there from somewhere else and set up populaces. Those species that did colonize the islands found numerous vacant biological specialties, nearby situations suited to supporting them, and missing predators that would avoid them from duplicating. In reaction, these species quickly expanded; this preparation of expanding to fill ecological niches is called adaptive radiation. Each of the world’s landmasses has it possess an unmistakable collection of creatures and plants. In Africa are rhinoceroses, hippopotamuses, lions, hyenas, giraffes, zebras, lemurs, monkeys with contract noses and no prehensile tails, chimpanzees, and gorillas. South America, which expands over much the same scopes as Africa, has none of these creatures; it instep has panthers, pumas, ungulate, llamas, raccoons, opossums, armadillos, and monkeys with wide noses and huge prehensile tails. These vagaries of biogeography are not due exclusively to the reasonableness of diverse situations. There's no reason to accept that South American creatures are not well suited to living in Africa or those of Africa to living in South America. The islands of Hawaii are no way better suited than other Pacific islands for vinegar flies, nor are they less affable than other parts of the world for numerous missing life forms. In reality, in spite of the fact that no expansive warm- blooded creatures are local to the Hawaiian islands, pigs and goats have multiplied there as wild animals since being presented by people. This nonattendance of numerous species from an affable environment in which an uncommon assortment of other species thrive can be clarified by the hypothesis of advancement, which holds that species can exist and advance as it were in geographic regions that were colonized by their ancestors. 17 MOLECULAR BIOLOGY The field of molecular biology provides the most detailed and convincing evidence available for biological evolution. In its unveiling of the nature of DNA and the workings of organisms at the level of enzymes and other protein molecules, it has shown that these molecules hold information about an organism’s ancestry. This has made it possible to reconstruct evolutionary events that were previously unknown and to confirm and adjust the view of events already known. The precision with which these events can be reconstructed is one reason the evidence from molecular biology is so compelling. Another reason is that molecular evolution has shown all living organisms, from bacteria to humans, to be related by descent from common ancestors. A remarkable uniformity exists in the molecular components of organisms— like the components as well as in how they are assembled and used. In all bacteria, plants, animals, and humans, the DNA comprises a different sequence of the same four-component nucleotides, and all the various proteins are synthesized from different combinations and sequences of the same 20 amino acids, although several hundred other amino acids do exist. The genetic code by which the information contained in the DNA of the cell nucleus is passed on to proteins is virtually everywhere the same. Similar metabolic pathways—sequences of biochemical reactions (see metabolism)—are used by the most diverse organisms to produce energy and to make up the cell components. This unity reveals the genetic continuity and common ancestry of all organisms. There is no other rational way to account for their molecular uniformity when numerous alternative structures are equally likely. The genetic code serves as an example. Each particular sequence of three nucleotides in the nuclear DNA acts as a pattern for the production of the same amino acid in all organisms. This is no more necessary than it is for a language to use a particular combination of letters to represent a particular object. If it is found that certain sequences of letters—planet, tree, woman—are used with identical meanings in several different books, one can be sure that the languages used in those books are of common origin. 18  Genes and proteins are long molecules that contain information in the sequence of their components in much the same way as sentences of the English language contain information in the sequence of their letters and words. The sequences that make up the genes are passed on from parents to offspring and are identical except for occasional changes introduced by mutations. As an illustration, one may assume that two books are being compared. Both books are 200 pages long and contain the same number of chapters. Closer examination reveals that the two books are an identical page for page and word for word, except that an occasional word—say, one in 100—is different. The two books cannot have been written independently; either one has been copied from the other, or both have been copied, directly or indirectly, from the same original book. Similarly, if each component nucleotide of DNA is represented by one letter, the complete sequence of nucleotides in the DNA of a higher organism would require several hundred books of hundreds of pages, with several thousand letters on each page. When the "pages" (or sequences of nucleotides) in these "books" (organisms) are examined one by one, the correspondence in the "letters" (nucleotides) gives unmistakable evidence of common origin. The two arguments presented above are based on different grounds, although both attest to evolution. Using the alphabet analogy, the first argument says that languages that use the same dictionary—the same genetic code and the same 20 amino acids—cannot be of independent origin. The second argument, concerning similarity in the sequence of nucleotides in the DNA (and thus the sequence of amino acids in the proteins), says that books with very similar texts cannot be of independent origin. The evidence of evolution revealed by molecular biology goes even further. The degree of similarity in the sequence of nucleotides or amino acids can be precisely quantified. For example, in humans and chimpanzees, the protein molecule called cytochrome c, which serves a vital function in respiration within cells, consists of the same 104 amino acids in the same order. It differs, however, from the cytochrome c of rhesus monkeys by 1 amino acid, from that of horses by 11 additional amino acids, and from that of tuna by 21 additional amino acids. The degree of similarity reflects the recency of common ancestry. Thus, the inferences from comparative anatomy and other disciplines concerning evolutionary history can be tested in molecular studies of DNA and proteins by examining their sequences of nucleotides and amino acids. (See below DNA and protein as informational macromolecules.) The authority of this kind of test is overwhelming; each of the thousands of genes and thousands of proteins contained in an organism provides an independent test of that organism’s evolutionary history. Not all possible tests have been performed, but many hundreds have been done, and not one has given evidence contrary to evolution. There is probably no other notion in any field of science that 19 has been as extensively tested and as thoroughly corroborated as the evolutionary origin of living organisms. Amino Acid Sequences in Cytochrome –C APPLICATION Directions: Answer the question below based on your understanding. 1. What are the differences between Homologous and Analogous Structures of organisms? Use this diagram. 20 REFLECT You did it well! Congratulations on finishing the supplementary learning module! Check out your ideas focusing on the lessons just learned and helped you attain the focus points intended for the lesson. But before you proceed to the next part, reflect on the picture and answer the following questions. Efforts to conserve threatened trout populations are helped by considering both the past and future evolution of the populations. Guide Questions: 1. Why is it difficult for a population with few individuals to survive? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 2. How does understanding evolution help us revitalize endangered populations? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 3. How does knowledge of evolutionary history help us make conservation decisions? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ 21 LEARN MORE! Since learning is considered a continuous process, I have a task for you; please have time to work on it. Visit the link provided below or search the title of the video on the internet. You are to make an article review. In your review, there should be, synopsis, points of agreement (if you agreed or not about the article), and your insights. Good luck! #Evolution #Biology #CharlesDarwin The Evolution of Humans | Science Full Documentary https://www.youtube.com/watch?v=_zN480tPFJQ) 22 REFERENCES Basco-Tiamzon, Maria Elena Z., et.al, GENERAL BIOLOGY 2 Textbook for Senior High School, Vibal Group, Inc., Quezon City, 2016 Online Resources https://www.expii.com/t/anatomical-and-physiological-evolution-evidence- types-10256 http://group4cladistics.weebly.com/analogous-and-homologous-traits.html https://www.pobschools.org/cms/lib/NY01001456/Centricity/Domain/517/AK% 20Evidences%20of%20evolution%20activityva411.pdf https://ontrack-media.net/gateway/biology/g_bm3l5rs6.html https://pigeonchess.com/2012/07/26/creationist-foists-fraudulent-embryo- picture-on-his-readers/ 23 For inquiries or feedback, please write or call: Department of Education – Schools Division of Surigao del Norte Peñaranda St., Surigao City Surigao del Norte, Philippines 8400 Tel. No: (086) 826-8216 Email Address: [email protected] 24