BZ220 1st Edition Lecture 2Outline of Last Lecture II. SyllabusA. Course ObjectivesB. GradingC. Homework ExpectationsD. Exam formatIII.What is evolution?A.DefinitionsB.Misnomers C.Effects IV. Why do we study evolution?A. What does evolution explainB. Applications of the study of evolutionV. Science vs. ReligionA. What’s science?B. Creation-evolution continuum C. MisconceptionsOutline of Current LectureI. Strong Inference and Multiple HypothesesII. Evidence of EvolutionA. Fossil RecordB. Homology C. Vestigial TraitsD. Age of EarthE. Direct Observation of ChangeIII. Pre-Darwin Evolution IdeasA. Scale of NatureThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.B. Carl LinnaeusC. Baron Georges CuvierD. Jean-Baptiste LamarckE. Charles Lyell Current Lecture2 components of scientific theory are: a statement about a pattern in the natural world and a process that explains the pattern. For evolution, the pattern in the natural world can be correlated to macroevolution where living organisms provide evidence of dramatic change and establishes a pattern. The process that explains macroevolution as a pattern is microevolution which involves monitoring populations and allows observation of small scale change and elucidates a process. Strong inference is one of the best ways to do science because it eliminates a researcher’s bias that might be present in a single hypothesis. Strong inference includes making observations about the natural world, devise multiple alternative hypotheses, seek out observations or conduct experiments that can exclude or falsify hypotheses, and repeat the above process making new hypotheses based on new observations. This idea was proposed by John Platte. The multiple hypotheses of evolution are there is no change at all, extinction does indeed occur, both extinction and lineage change occurs over time, and there is a complex tree of life with extinction, changing lineages, AND common descent. The first piece of evidence that tested these four hypotheses was the fossil record. The fossil record is defined as any trace of organism that have lived in the past. Due to several factors, the fossil record is not a complete and fully accurate way of knowing the past. First of all, fossils are often only found in sedimentary rocks not igneous and metamorphic for the process of heating and change in these last 2 rock formations make it hard for a fossil to survive through time. Because of this challenge and the low probability events that material will be preserved before decomposition, rock is exposed, and someone finds the rock that is exposed, very little fossils are actually found. When a fossil is found we only know morphological characters such as bone structure and must infer the physiology and behavior of the extinct animal.In order for fossilization to occur, sedimentation in a low energy environment with basic soil is necessary for the fossil to be promptly and properly buried to prevent decomposition. If a good fossil is found, it must also be preserved in order to continue to be useful. Modes of preservation include carbon replicating, casting, mineralization, and amber (hardened tree sap).When a fossil is found and observed, it can help to estimate the time line of evolution through the principle of superposition (position of rock layers) and radioactive decay through methods such as carbon dating. Once fossils are found and can show that it is from an extinct not extant species, hypothesis one of no change in evolution can be refuted. Furthermore, the fossil record can prove the law of succession where fossils are similar to other fossils above and below adjacent rock layers and fossils are similar to living organisms found in the same locations. When this law of succession is proven in combination with the findings of transitional fossil forms like Archaeopteryx it indicates that fossils are descendants of earlier species and ancestors of living species. Because of this indication, hypothesis 2 that only extinction occurs can be refuted. Hypothesis 3 can then be tested and eventually refuted due to the similarities among living species as well as the age of earth. Similarities among living species shows that evolution occurs through adaptations of what is already present in an ancestor. For example homology (the similarity between species due to inheritance of traits from a shared common ancestor) proves that traits can have similar or different functions that may not always be the most efficient design. For instance the ovipositor of a female wasp was adapted into a stinger in bumblebees where once used the bee will eventually die. Another form of homology are vestigial traits which indicate common ancestry. Vestigial traits are functionless or reduced traitsthat are similar to functional traits in closely related species. A few examples of vestigial traits include wings on flightless birds and eyes in blind cave fish. Vestigial DNA is also an example of homology. Vestigial DNA sequences that are similar to known functional genes but don’t produce a gene product are known as pseudogenes. In addition to homology, the idea that earth is old is required for ancestry. Enough time for gradual accumulation of small changes from a shared common ancestor to result in diversity of life today. When the old age of earth is combined with fossil patterns and homology, hypothesis 3 is refuted and hypothesis 4 that a complex tree of life with extinction, changing lineages, and common descent is supported. Hypothesis 4 is also supported because there can be a direct observation of change needed for this hypothesis. An example of direct observation is soapberry bugs have experienced changes in beak length increase on new hosts of balloon vines instead of the shorter beak necessary for flat-podded golden rain tree hosts.In the Early 1700s, Greeks and Romans used to believe that species on earth did not change and life was on a progressive scale with humans at the top and plants towards the bottom, for earth was too young for evolution to occur. This idea has since then been frowned upon. The next step of pre-evolutionary ideas was Carl Linnaeus idea of taxonomy and systematics. His system whose hierarchy was based on similarity among species is still around today. The system of taxonomy from most inclusive to least inclusive is as follows: domain, kingdom,