BIO120 Fall 2024 Lecture 1 (PDF)

Welcome to BIO120! An introduction to the principles and concepts of evolution and ecology, related to the origins of adaptation and biodiversity. © BIO120 Fall 2024  The BIO120 Team Luke Mahler Megan Frederickson...

Welcome to BIO120! An introduction to the principles and concepts of evolution and ecology, related to the origins of adaptation and biodiversity. © BIO120 Fall 2024  The BIO120 Team Luke Mahler Megan Frederickson Jill Wheeler Jill Romy Laura Veronica Technicians + Lab (Lecture TAs) TAs © BIO120 Fall 2024 The course syllabus contains all essential course information. It is posted on Quercus Please read it carefully © BIO120 Fall 2024 The BIO120 course site is on U of T’s Quercus q.utoronto.ca © BIO120 Fall 2024 What can you find on Quercus? Course syllabus Lecture slides & video Quizzes Online assignment submission Test information Discussion boards Everything! © BIO120 Fall 2024  Important! Turn on “Announcements” in your Quercus Notifications Only contact course staff STOP! through email – DO NOT Send an use the Quercus Inbox email instead! function! © BIO120 Fall 2024  Required course materials 1 2 3 $11.05 Free eBook $12.00 through UofT Details posted on Quercus Library 4 Lab coat © BIO120 Fall 2024  Labs Week 1 labs (P**01) start next week (Sept 9-13). Week 2 labs (P**02) start week of Sept 16-20. Check “Grades” on Quercus after 5:00pm on Mon Sept 9 to determine your lab code. What if you are not enrolled on ACORN in a lab? Starting Sept 10, email [email protected] with a screenshot of your ACORN timetable attached © BIO120 Fall 2024  Questions about BIO120? Academic (Lecture) 1. Optional weekly tutorials with professors Alternating Mondays 4:10-5pm and Wednesdays 9:10-10am Located in Ramsay Wright room 432 Con Hall © BIO120 Fall 2024  Questions about BIO120? Academic (Lecture) 1. Optional weekly tutorials with professors Alternating Mondays 4:10-5pm and Wednesdays 9:10-10am Located in Ramsay Wright room 432 2. Lecture Discussion Forum on Quercus Romy Suliteanu Jill Sanderson © BIO120 Fall 2024  Questions about BIO120? Academic (Lab) 1. Office hours 2. Lab Discussion Forum on Quercus Jill Wheeler Administration (missed labs, test conflict, etc.) 1. Email [email protected] 2. BIO120 Office is in Ramsay Wright room 105; office hours posted on Quercus Laura Heslin Piper Veronica Chong © BIO120 Fall 2024  Beyond BIO: Optional activities for BIO120 students What is Beyond BIO? A series of optional events offered to BIO120 students throughout the course. They are meant to be fun and informative for any students who are interested. For more information, event locations, and the complete schedule for this term, see Quercus under Modules  Beyond BIO. Upcoming Events: BIO120 Social! Thursday September 12th at 5:00 pm Start the term with a fun evening of snacks and trivia! Meet your classmates and enjoy refreshments – everyone is welcome! Birds & Wildlife of Toronto Thursday September 19th from 11:10 am – 12:00 pm Learn about Toronto’s local wildlife, find out the best spots to see nature in the city, and learn how to be a naturalist. Refreshments & snacks provided! © BIO120 Fall 2024 Enjoy the course! Bernd Thaller/ Flickr.com © BIO120 Fall 2024  BIO120: Adaptation and biodiversity Introduction to evolutionary biology Relevant reading in Charlesworth & Charlesworth – Chapter 1 This lecture will be recorded and posted on Quercus. 14 © BIO120 Fall 2024 D. Luke Mahler Research Interests: Assoc. Prof. Phylogenetics EEB Dept. Macroevolution BA, U. Chicago Community ecology PhD, Harvard U. Anolis lizards 15 © BIO120 Fall 2024 Readings 1) Charlesworth & Charlesworth “Evolution: A Very Short Introduction” 2) Assumed background knowledge (i.e. to know from high school): Mendelian genetics 16 © BIO120 Fall 2024 Lecture 1 Outline 1) What is evolutionary biology? 2) How is evolution studied? 3) Why is it relevant to you? 17 © BIO120 Fall 2024 The Theory of Evolution The central unifying concept of biology Affects many other areas of knowledge One of the most influential concepts of Western thought 18 © BIO120 Fall 2024 The Theory of Evolution The Two Core Tenets of Evolution 1) Living things change over time 2) Adaptations have arisen through natural selection Evolution challenges the view of special creation (= direct creation of all living things in effectively their present form) 19 © BIO120 Fall 2024 The Theory of Evolution Important Conclusions About Evolution Verified by Scientific Study Organisms on Earth have changed through time The changes are gradual not instantaneous* Lineages split by speciation, resulting in the generation of biodiversity All species have a common ancestor Adaptations result from natural selection Biodiversity and adaptation are therefore products of evolution 20 Adapted from Mayr, 1991, One Long Argument © BIO120 Fall 2024 The Theory of Evolution Some simple definitions: Biodiversity The diversity of life on Earth The number and kinds of living organisms in a given area Adaptation (has two meanings; state or process) Any trait that makes an organism better able to survive or reproduce in a given environment [as a noun] The evolutionary process that leads to the origin and maintenance of such traits [as a verb] 21 © BIO120 Fall 2024 Biodiversity & Adaptation: A Beautiful Evolutionary Legacy 22 © BIO120 Fall 2024 The Theory of Evolution Major areas of evolutionary study: Microevolution: Evolutionary history (i.e., patterns) Evolutionary patterns and processes observed within species. Evolutionary mechanisms (i.e., processes) Macroevolution: Evolutionary patterns and processes observed among species. Macroevolution Evolutionary Evolutionary History Mechanism Microevolution 23 © BIO120 Fall 2024 The Theory of Evolution Evolutionary History Goals Determine the evolutionary relationships of organisms in terms of common ancestry Identify and understand long‐term patterns in evolution In Practice Uses comparative data from sub‐disciplines of systematics, biogeography, paleontology, morphology, development, and molecular biology 24 © BIO120 Fall 2024 The Theory of Evolution Evolutionary History: Understanding Evolutionary Trees For Our Purposes: an evolutionary tree Genealogy information represented as a tree graph = a phylogenetic tree = a phylogeny 25 © BIO120 Fall 2024 The Theory of Evolution Evolutionary History: Phylogeny of Our Recent Past Rotation of branches on tree retains same information 26 © BIO120 Fall 2024 The Theory of Evolution Evolutionary History: Phylogeny of Ancient Evolution Trees with different sets of species can represent the same common ancestors 27 © BIO120 Fall 2024 The Theory of Evolution Evolutionary Mechanisms Goals Determine the particular processes responsible for evolutionary change (e.g., natural selection) Identify the major forces of evolution In Practice Uses experimental and comparative studies of the genetics and ecology of populations Focuses primarily on the population level 28 © BIO120 Fall 2024 How Is Evolution Studied? A variety of approaches are used to address scientific questions: Observational – describe and quantify Theoretical – develop models: verbal, graphical, mathematical, computational Comparative – obtain same data from many species Experimental – manipulate a system to address a specific hypothesis; requires an experimental design and statistical analysis Scientific theories have testable and falsifiable hypotheses. The strongest studies use more than one source of evidence. 29 © BIO120 Fall 2024 How Is Evolution Studied? Evolution of Self‐Fertilization Capsella grandiflora Capsella bursa‐pastoris 30 © BIO120 Fall 2024 How Is Evolution Studied? Evolution of Self‐Fertilization 1) Why does self‐fertilization evolve? (theory, observations, experiments in the field) 2) How did self‐fertilization evolve? (genetic crosses, molecular biology, developmental biology) 3) When did selfing evolve? (evolutionary history, analysis of genetic differences) 4) What are the consequences of evolving selfing? (genome studies) 31 © BIO120 Fall 2024 Why Is Evolution Relevant? 1) Children’s questions 2) Medicine 3) Agriculture 4) Environment 5) Understanding Life on Earth (Biology!!!) 32 © BIO120 Fall 2024 Why Is Evolution Relevant? 1) Children’s Questions Where did the first person come from? 33 © BIO120 Fall 2024 Why Is Evolution Relevant? 2) Medicine Influenza COVID‐19 34 © BIO120 Fall 2024 Why Is Evolution Relevant? 2) Medicine 35 https://nextstrain.org/ncov/gisaid/global/all‐time?d=tree,entropy,frequencies&p=full © BIO120 Fall 2024 Why Is Evolution Relevant? 2) Medicine 36 https://nextstrain.org/ncov/gisaid/global/all‐time?d=tree,entropy,frequencies&p=full © BIO120 Fall 2024 Why Is Evolution Relevant? 2) Medicine Questions in Evolutionary Medicine 1) Can we predict cancer evolution? 2) Can we design evolution‐proof drug treatments against pathogens? 3) Why are many diseases common only in certain human populations? 4) What are the origins of viruses and bacteria in human populations? 37 © BIO120 Fall 2024 Why Is Evolution Relevant? 3) Agriculture 38 © BIO120 Fall 2024 Why Is Evolution Relevant? 3) Agriculture Evolutionary Questions in Agriculture 1) How can we design strategies to avoid herbicide and insecticide‐resistant superweeds/super pests? 2) What genes were important for crop evolution? 39 © BIO120 Fall 2024 Why Is Evolution Relevant? 4) Environment 40 © BIO120 Fall 2024 Why Is Evolution Relevant? 5) Biology!!!! “Nothing in biology makes sense except in the light of evolution.” ‐ Theodosius Dobzhansky (1973) Lynn Margulis and the theory of endosymbiosis Tackling the “why” questions for any topic in biology requires an understanding that organisms share an evolutionary history Complex traits can be understood in the context of Darwinian evolution by natural selection 41 © BIO120 Fall 2024 Public Doubts About Evolution 1) Extremely recent scientific concept! (165 years is a very brief timeframe) 2) Very ‘personal’ implications: direct ramifications about who we are and where we came from 3) Violates literal interpretations of religious texts – also true of other sciences as well, e.g., geology, astronomy, physics, biochemistry EKOS 2022 42 © BIO120 Fall 2024 Public Doubts About Evolution Evolution has as much empirical support as any other accepted scientific theory. 43 © BIO120 Fall 2024 Grandeur in this View of Life “There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.” Charles Darwin, Origin of Species 44 © BIO120 Fall 2024 Recap Vocabulary / recall: adaptation, biodiversity, evolutionary history, evolutionary mechanism, microevolution, macroevolution. Concepts: Phylogenetic trees; approaches to studying evolution; implications and applications of evolution Scientific theories as testable and falsifiable, as opposed to faith and belief (note, mastering the info on these recap slides is necessary but not sufficient) 45 © BIO120 Fall 2024 Next Lecture: Darwin’s big idea and how it changed biology 46 © BIO120 Fall 2024