Evolutionary Evidence PDF

General Biology 2 DEVELOPMENT OF EVOLUTIONARY THOUGHT LESSON OBJECTIVES: Recognize prominent scientists who have contributed to the idea of biological evolution; Explain the theory of evolution; and Appreciate proposed theories based on learned concepts in science. CONCEPT: Bef...

General Biology 2 DEVELOPMENT OF EVOLUTIONARY THOUGHT LESSON OBJECTIVES: Recognize prominent scientists who have contributed to the idea of biological evolution; Explain the theory of evolution; and Appreciate proposed theories based on learned concepts in science. CONCEPT: Before the nineteenth century, the idea that organisms changed through time and that a number of organisms that once have existed on Earth have disappeared completely, was unacceptable. Vocabulary: 1. Evolution – is the gradual process of change that transformed life on Earth. 2. Evolutionary Theory – is the area that focuses on further development and refinement of the modern synthesis of evolution and genetics  Pioneers of Theories of Evolution George Cuvier Jean-Baptiste Lamarck Charles Darwin  Pioneers of Theories of Evolution 1. George Cuvier (1769- 1832) - French zoologist and paleontologist - Provided some of the earliest evidence showing that there were organisms that have existed before which no longer existed during his time  Pioneers of Theories of Evolution 1. George Cuvier (1769-1832)  IDEA: Catastrophism  He wondered how fossilized seashells ended up on the mountain side far from the seas. The only explanation he could come up with that was the geologic forces raised seafloors in a short span of time. Therefore, he proposed that a geologic catastrophe must have caused the extinction and re- population of the area was made by organisms that survived the catastrophe.  Pioneers of Theories of Evolution 2. Jean-Baptiste Lamarck (1744-1829) - French Naturalist - He urged that the living organisms slowly change to be better and better until they reach the state of PERFECTION  Pioneers of Theories of Evolution 2. Jean-Baptiste Lamarck (1744-1829) Fluida – liquid component in an organism’s body - goes to the part of the body that needs to change as directed by the environment IDEA: Inheritance of Acquired Characteristics The theory explains that some of the giraffes must have strained their necks just to reach the leaves, while some failed to do the same and so they died. When these giraffes reproduced they passed on their trait through time to their offspring. Since then, all giraffes had long necks. We know that this concept is false. Why? He was still widely CREDITED.  Body changes due to an organism’s behavior or experience that occur within an organism’s life could then be passed on to offspring EXAMPLES: Webbed foot of water birds – the repeated stretching of membrane between the toes was passed on to offspring Organisms not using tail would produce offspring with smaller tails Darwin VS. Lamarck  Pioneers of Theories of Evolution 3. Charles Darwin (1809-1882)  English naturalist, geologist and biologist  Father of Evolution  He studied medicine but was not able to finish the course in college  He then studied theology which he was able to complete  Pioneers of Theories of Evolution 3. Charles Darwin (1809-1882) In 1835, he went to Galapagos Island off the coast of South America and began to collect specimens from 4 islands in Galapagos. He noticed that these islands have basically the same species of organisms with only slight difference.  Pioneers of Theories of Evolution 3. Charles Darwin (1809-1882) They noticed that Darwin’s finches were separate species that cannot be seen in the mainland of South America. But what is remarkable was that the finches bear similarities with existing birds from mainland. This made Darwin think that the birds that came from the mainland reached the volcanic islands of Galapagos and gradually changed. Darwin’s Galápagos Finches Beak Variation  Charles Lyell (1797 – 1875) developed the theory of uniformitarianism. The theory that the earth’s features are the result of long term processes that continue to operate in the present as they did in the past. Elaborated on by Lyell, this theory opposed catastrophism and contributed strongly to the concept of immense geological time.  Alfred Russell Wallace (1823- 1913) A naturalist who worked in South America and Southeast Asia. Suggested species descended from other species and new species were influenced by environmental factors. Presented paper on evolution and natural selection to the Linnean Society of London jointly with Darwin.  Thomas Malthus (1766 – 1834) wrote about relationship between food supply and population increase. His essay on the Principle of Population led both Darwin and Wallace to the principle of natural selection. 4 Basic Principles of Natural Selection Variation Heritability Overproduction Reproductive Advantage  Four Basic Principles of Natural Selection 1.Variation  Darwin observed that species of organisms that seemed similar are in fact different at the same time.  The finches from the islands, as well as those from the mainland, share the SAME general anatomy, size and coloration but still had differences among them  These differences according to Darwin, suited the bird to the environment they inhabit  Four Basic Principles of Natural Selection 2. Heritability  States that the variation in traits of individuals may be passed on to their offspring He observed its occurrence in the artificial or selective breeding  Four Basic Principles of Natural Selection 3. Overproduction  He reasoned that populations of all species have the capacity to grow. Simply put, species produce more offspring than can survive  Situation to support his belief: One cardinal (bird) can lay 9 eggs and if all 9 can were to survive and bear the same number of eggs, in one generation there will be 90 cardinals, assuming the first cardinal had already died.  Four Basic Principles of Natural Selection 4. Reproductive Advantage  Darwin believed that with all the variations of individuals of a population, some traits allow individuals to gain more advantage in terms of fitness. These traits may be anatomical or physical, behavioral or psychological  Example: White tigers have powerful jaws & teeth, very strong sense of smell, sharp eyesight and excellent swimmers Evidence of Evolution CONCEPT: Scientists trace the history of organisms through the evidences gathered through different evidences. Biogeography Paleontology Homology Embryology Fossil Record  EVIDENCE OF EVOLUTION 1.Biogeography It is the study of the geographical distribution of organisms, provides information about how and when species may have evolved. It is the study of distribution of plants and animals in a geographic space through the geologic time  EVIDENCE OF EVOLUTION 2. Paleontology It is the science that deals with the study of fossils Fossils are the remains of plants, animals, fungi, bacteria, and single-celled living things that have been replaced by rock material or impressions of organisms preserved in rock EVIDENCE OF EVOLUTION 3. Homology - refers to the similarity of parts of different organisms caused by evolutionary derivation of corresponding part from remote ancestor  EVIDENCE OF EVOLUTION 4. Embryology It is the study of the development of organisms from conception to birth EVIDENCE OF EVOLUTION 5. Fossil Record It is a revealing window into species that lived long ago. The history of life as documented by fossils, the remains or imprints of organisms from earlier geological periods preserved in sedimentary rock  Proof of Evolution https://youtu.be/rFxu7NEoKC8